You searched for subject:(CONTRAST SENSITIVITY).
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Dalhousie University
1.
Betts, Michael John.
Radial Deformation Acuity In Children With Amblyopia.
Degree: MS, Department of Clinical Vision Science, 2013, Dalhousie University
URL: http://hdl.handle.net/10222/21727 
► Purpose: To examine the relationship between visual acuity (VA) and radial deformation acuity (RDA) in children 6 to 12 years of age with amblyopia. Methods:…
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▼ Purpose: To examine the relationship between visual
acuity (VA) and radial deformation acuity (RDA) in children 6 to 12
years of age with amblyopia. Methods: RDA was measured in 35
participants with the Manchester RDA charts. VA was measured with
the Early Treatment Diabetic Retinopathy Research Study (ETDRS)
chart. Results: Median VA in non-amblyopic and amblyopic eyes was
0.04 logMAR (IQF -0.06 – 0.12) and 0.24 (IQF 0.12 – 0.04),
respectively (Wilcoxon Signed Ranks test, z = -5.07, p < 0.001).
Median RDA in non-amblyopic and amblyopic eyes was 2.73 log (IQF
2.53 – 2.87) and 2.63 log (IQF 2.53 – 2.77), respectively
(Wilcoxon, z = -2.56, p < 0.05). Spearman correlation suggested
that the amblyopic deficits in VA and RDA were related, r = -0.42,
p < 0.05. Conclusion: A deficit in RDA was present in most
children with amblyopia. A moderate relationship was noted between
the amblyopic deficits found in VA and RDA.
Advisors/Committee Members: Dr. Nathan Crowder (external-examiner), Dr. Balwantray Chauhan (graduate-coordinator), Leah Walsh (thesis-reader), Dr. Francois Tremblay (thesis-reader), Karen McMain, Dr. Paul H. Artes (thesis-supervisor), Received (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Amblyopia; Hyperacuity; Radial Deformation Acuity; Contrast Sensitivity
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APA (6th Edition):
Betts, M. J. (2013). Radial Deformation Acuity In Children With Amblyopia. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/21727
Chicago Manual of Style (16th Edition):
Betts, Michael John. “Radial Deformation Acuity In Children With Amblyopia.” 2013. Masters Thesis, Dalhousie University. Accessed January 18, 2021.
http://hdl.handle.net/10222/21727.
MLA Handbook (7th Edition):
Betts, Michael John. “Radial Deformation Acuity In Children With Amblyopia.” 2013. Web. 18 Jan 2021.
Vancouver:
Betts MJ. Radial Deformation Acuity In Children With Amblyopia. [Internet] [Masters thesis]. Dalhousie University; 2013. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/10222/21727.
Council of Science Editors:
Betts MJ. Radial Deformation Acuity In Children With Amblyopia. [Masters Thesis]. Dalhousie University; 2013. Available from: http://hdl.handle.net/10222/21727
University of Bradford
2.
Longley, Christopher I.
Contrast sensitivity and glare : new measurement techniques and the visual consequences of wearing head-mounted displays.
Degree: PhD, 2016, University of Bradford
URL: http://hdl.handle.net/10454/16061
► The main aim of this thesis was to evaluate the performance of the contrast sensitivity clock (CSC), a new screening device for measuring contrast sensitivity…
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▼ The main aim of this thesis was to evaluate the performance of the contrast sensitivity clock (CSC), a new screening device for measuring contrast sensitivity (CS) and glare. This device allows CS without glare, with glare and disability glare scores to be recorded. After initial data collection the design of the CSC was slightly amended improving the performance of the device. The amended design of the CSC was shown to be a valid, discriminative and repeatable measure for purpose. The CSC is also a quick test to perform and is relatively cheap to produce. If all these factors are considered it shows potential to become the test of choice for the assessment of visual glare. A head-mounted display system was also evaluated in terms of the glare effects it may cause. The monocular display screen of the device significantly reduced the CS of the eye directly exposed but also had an effect on binocular performance, reducing amounts of binocular summation. Electronic devices, including head-mounted displays and satellite navigation systems can seriously affect CS at low luminance levels, similar to those found when driving at night.
Subjects/Keywords: 570; Disability glare; Binocular summation; Binocular inhibition; Google Glass; Contrast sensitivity clock (CSC); Contrast sensitivity (CS); Head-mounted display (HMD)
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APA (6th Edition):
Longley, C. I. (2016). Contrast sensitivity and glare : new measurement techniques and the visual consequences of wearing head-mounted displays. (Doctoral Dissertation). University of Bradford. Retrieved from http://hdl.handle.net/10454/16061
Chicago Manual of Style (16th Edition):
Longley, Christopher I. “Contrast sensitivity and glare : new measurement techniques and the visual consequences of wearing head-mounted displays.” 2016. Doctoral Dissertation, University of Bradford. Accessed January 18, 2021.
http://hdl.handle.net/10454/16061.
MLA Handbook (7th Edition):
Longley, Christopher I. “Contrast sensitivity and glare : new measurement techniques and the visual consequences of wearing head-mounted displays.” 2016. Web. 18 Jan 2021.
Vancouver:
Longley CI. Contrast sensitivity and glare : new measurement techniques and the visual consequences of wearing head-mounted displays. [Internet] [Doctoral dissertation]. University of Bradford; 2016. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/10454/16061.
Council of Science Editors:
Longley CI. Contrast sensitivity and glare : new measurement techniques and the visual consequences of wearing head-mounted displays. [Doctoral Dissertation]. University of Bradford; 2016. Available from: http://hdl.handle.net/10454/16061
San Jose State University
3.
Tomko, Linda.
Impact of Correlated and Uncorrelated Noise on Binocular Perception.
Degree: MS, Industrial and Systems Engineering, 2014, San Jose State University
URL: https://doi.org/10.31979/etd.v95b-rmhs
;
https://scholarworks.sjsu.edu/etd_theses/4518
► Numerous studies have established advantages of binocular over monocular vision, including increased contrast sensitivity arising as a result of binocular summation. However, there remains…
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▼ Numerous studies have established advantages of binocular over monocular vision, including increased contrast sensitivity arising as a result of binocular summation. However, there remains inadequate understanding regarding several aspects of binocular summation. The present study sought greater understanding of factors potentially broadening, or limiting, the extent to which binocular summation explanations can be applied. In particular, binocular summation effects have not been adequately investigated within the context of external visual displays presenting dynamic noise. The present study investigated whether dichoptic viewing of a signal in uncorrelated visual noise conditions confers a perceptual advantage over that in correlated noise in visual detection and discrimination tasks. A repeated-measures design was utilized, manipulating noise type and level of noise correlation presented through a head-worn display device. The dynamic externally presented noise included characteristics resembling night vision goggle (NVG) noise, while levels of correlation emulated the physical image configuration of NVG device types (binocular and biocular). An adaptive 1-up/2-down staircase procedure was used to obtain contrast sensitivity threshold estimates. Results did not adhere to established binocular summation model predictions, and differences were inconclusive of any perceptual advantage in uncorrelated noise conditions. Discussion addresses potential limiting factors to the study results.
Subjects/Keywords: binocular summation; biocular; contrast sensitivity; dichoptic displays; display noise; fusion
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APA (6th Edition):
Tomko, L. (2014). Impact of Correlated and Uncorrelated Noise on Binocular Perception. (Masters Thesis). San Jose State University. Retrieved from https://doi.org/10.31979/etd.v95b-rmhs ; https://scholarworks.sjsu.edu/etd_theses/4518
Chicago Manual of Style (16th Edition):
Tomko, Linda. “Impact of Correlated and Uncorrelated Noise on Binocular Perception.” 2014. Masters Thesis, San Jose State University. Accessed January 18, 2021.
https://doi.org/10.31979/etd.v95b-rmhs ; https://scholarworks.sjsu.edu/etd_theses/4518.
MLA Handbook (7th Edition):
Tomko, Linda. “Impact of Correlated and Uncorrelated Noise on Binocular Perception.” 2014. Web. 18 Jan 2021.
Vancouver:
Tomko L. Impact of Correlated and Uncorrelated Noise on Binocular Perception. [Internet] [Masters thesis]. San Jose State University; 2014. [cited 2021 Jan 18].
Available from: https://doi.org/10.31979/etd.v95b-rmhs ; https://scholarworks.sjsu.edu/etd_theses/4518.
Council of Science Editors:
Tomko L. Impact of Correlated and Uncorrelated Noise on Binocular Perception. [Masters Thesis]. San Jose State University; 2014. Available from: https://doi.org/10.31979/etd.v95b-rmhs ; https://scholarworks.sjsu.edu/etd_theses/4518
4.
Martins, Cristiane Maria Gomes.
Impacto da catarata congênita na sensibilidade ao contraste espacial de luminância em crianças.
Degree: Mestrado, Neurociências e Comportamento, 2012, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/47/47135/tde-15032013-105656/
;
► A opacificação do cristalino presente ao nascimento ou nos primeiros meses de vida é denominada de Catarata Congênita (CC). As primeiras semanas de vida são…
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▼ A opacificação do cristalino presente ao nascimento ou nos primeiros meses de vida é denominada de Catarata Congênita (CC). As primeiras semanas de vida são importantes no desenvolvimento visual, já que há diferença significativa no desempenho visual de crianças que passaram pela cirurgia até seis semanas de vida (com melhor desempenho visual) em relação às crianças que realizaram a cirurgia após seis semanas de vida. Crianças que tiveram privação visual durante a primeira infância por catarata bilateral apresentam redução da visão espacial. O objetivo deste trabalho foi verificar o impacto na Função de Sensibilidade ao Contraste (FSC) em crianças de tratamento cirúrgico de Catarata Congênita, durante a fase de desenvolvimento visual. Foram avaliados três grupos: 11 crianças do grupo controle (média idade =6,83; DP=1,38), 9 crianças do grupo CC (média idade =6,87; DP=2,03) e 15 indivíduos adultos (média idade =27,63; DP=4,16). Foi utilizado o software Metropsis para avaliação da sensibilidade ao contraste de luminância de grade senoidal nas frequências espaciais de 0,2 cpg; 0,5 cpg; 1,0 cpg; 2,0 cpg; 4,2 cpg e 8,9 cpg e luminância média de 34,4 cd/m². Houve redução em toda a curva de sensibilidade ao contraste (SC) do grupo CC quando comparado ao grupo controle e não houve relação entre o tempo de privação e a redução da SC
The opacification of the lens present at birth is called Congenital Cataract (CC). The first weeks of life are important in visual development since there is not any significant difference in visual performance of children who had surgery within six weeks of life (with better visual performance) compared with children who underwent surgery after this period. Children who have visual deprivation during infancy due to bilateral cataracts have reduced spatial vision. The aim of this study was to assess the impact on Contrast Sensitivity Function (CSF) in children with Congenital Cataract surgery during the visual development age range. We evaluated three groups: 11 control children (mean age = 6.83, SD = 1.38), 9 children in the CC group (mean age = 6.87, SD = 2.03) and 15 adults (mean age = 27.63, SD = 4.16). Metropsis software was used to evaluate sensitivity to luminance contrast of the sinusoidal grating spatial frequencies of 0.2 cpd, 0.5 cpd, 1.0 cpd, 2.0 cpd, 4.2 cpd and 8.9 cpd with an average luminance of 34.4 cd / m². There was a reduction in the contrast sensitivity function (CSF) of the CC group compared to the control group and there was no correlation between the duration of deprivation and the impairment in the SC
Advisors/Committee Members: Costa, Marcelo Fernandes da.
Subjects/Keywords: Cataract (congenital); Catarata (congênito); Contrast sensitivity; Contraste; Psicofísica; Psychophysics
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APA (6th Edition):
Martins, C. M. G. (2012). Impacto da catarata congênita na sensibilidade ao contraste espacial de luminância em crianças. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/47/47135/tde-15032013-105656/ ;
Chicago Manual of Style (16th Edition):
Martins, Cristiane Maria Gomes. “Impacto da catarata congênita na sensibilidade ao contraste espacial de luminância em crianças.” 2012. Masters Thesis, University of São Paulo. Accessed January 18, 2021.
http://www.teses.usp.br/teses/disponiveis/47/47135/tde-15032013-105656/ ;.
MLA Handbook (7th Edition):
Martins, Cristiane Maria Gomes. “Impacto da catarata congênita na sensibilidade ao contraste espacial de luminância em crianças.” 2012. Web. 18 Jan 2021.
Vancouver:
Martins CMG. Impacto da catarata congênita na sensibilidade ao contraste espacial de luminância em crianças. [Internet] [Masters thesis]. University of São Paulo; 2012. [cited 2021 Jan 18].
Available from: http://www.teses.usp.br/teses/disponiveis/47/47135/tde-15032013-105656/ ;.
Council of Science Editors:
Martins CMG. Impacto da catarata congênita na sensibilidade ao contraste espacial de luminância em crianças. [Masters Thesis]. University of São Paulo; 2012. Available from: http://www.teses.usp.br/teses/disponiveis/47/47135/tde-15032013-105656/ ;
5.
Moreira, Sonia Maria Cipriani Fersura.
Desenvolvimento da sensibilidade ao contraste de luminância espacial e temporal.
Degree: Mestrado, Psicologia Experimental, 2010, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/47/47132/tde-21102010-110538/
;
► Objetivo: Avaliar a Função de Sensibilidade ao Contraste de Luminância Espacial e Temporal, estudar o desenvolvimento destas funções, a contribuição das vias de processamento paralelo…
(more)
▼ Objetivo: Avaliar a Função de Sensibilidade ao Contraste de Luminância Espacial e Temporal, estudar o desenvolvimento destas funções, a contribuição das vias de processamento paralelo para as funções de Sensibilidade ao Contraste e seu respectivo desenvolvimento e, por fim, determinar valores normativos destas funções visando uma aplicabilidade clínica.Método A avaliação psicofísica de sensibilidade ao contraste de luminância espacial e temporal foi realizada em 112 sujeitos divididos em três grupos:GrupoI ( idade média =9,14±2,7 anos),Grupo II ( idade média=23,7 ± 3,4 anos) e Grupo III ( idade média=41,8± 5,5 anos) com o programa PSYCHO for Windows Versão 2.36 (Cambridge Research Systems, CRS-Ltd, UK) acoplado a um microcomputador PC XTC -600. . Os estímulos foram apresentados em um monitor Sony Triniton de 19 polegadas GFD420 (Sony Corporation, USA) com resolução espacial de 800X600 e resolução temporal de 69 Hz Os estímulos eram comandados pela placa gráfica VSG 2/4 (Cambridge Research Systems, CRS-Ltd, UK).Resultados A avaliação psicofísica para a sensibilidade ao contraste espacial e temporal mostraram que esta função já está desenvolvida e em pleno funcionamento em crianças (6 anos) ocorrendo um declínio para as frequências espaciais de 2,0cpg;8,3cpg e 14,5cpg para os grupos II e III.Para a frequência temporal de 2,5Hz o declínio ocorre nos Grupos II e III e para a frequência temporal de 5,0 Hz nas idades mais avançadas(GIII). Para o estudo da contribuição das vias de processamento paralelo (magnocelular e parvocelular) podemos notar uma maior sensibilidade ao contraste para decremento de luz do que para incremento de luz, porém não foi possível determinar a real contribuição dessas vias para a função de sensibilidade ao contraste. Conclusão Avaliamos com sucesso a Sensibilidade ao Contraste Espacial e Temporal para todas as faixas etárias e, assim, conseguimos ter acesso ao desenvolvimento desta função, entre as idades de 6 e 57 anos. Valores normativos para as tais funções foram estabelecidos por metodologia nãoparamétrica.. O estudo da contribuição das vias magnocelular e parvocelular não pode ser conclusivo, porém os achados mostraram uma maior sensibilidade para o decremente de luz o que corrobora com a literatura
Purpose: To analyze the spatial and temporal luminance contrast sensitivity function, to study the development of these functions, the contribution of the parallel processing pathways and to determine the normative values of these functions to order a clinical applicability normative. Methods the psychophysical evaluation of the spatial and temporal luminance contrast sensitivity was performed in 112 subjects divided into three groups: Group I (mean age =9.14±2.7 years), Group II (mean age=23.7 ± 3.4 years) and Group III (mean age=41.8± 5.5 years) with the PSYCHO for Windows Version 2.36 (Cambridge Research Systems, CRS-Ltd, UK) connect to the microcomputer PC XTC -600. The stimuli was showed in a monitor Sony Triniton de 19 inches GFD420 (Sony Corporation, USA) with spatial resolution of the…
Advisors/Committee Members: Costa, Marcelo Fernandes da.
Subjects/Keywords: Psicofísica; Psychophysics; Sensibilidade de contraste visual; Visão; Vision; Visual contrast sensitivity
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APA (6th Edition):
Moreira, S. M. C. F. (2010). Desenvolvimento da sensibilidade ao contraste de luminância espacial e temporal. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/47/47132/tde-21102010-110538/ ;
Chicago Manual of Style (16th Edition):
Moreira, Sonia Maria Cipriani Fersura. “Desenvolvimento da sensibilidade ao contraste de luminância espacial e temporal.” 2010. Masters Thesis, University of São Paulo. Accessed January 18, 2021.
http://www.teses.usp.br/teses/disponiveis/47/47132/tde-21102010-110538/ ;.
MLA Handbook (7th Edition):
Moreira, Sonia Maria Cipriani Fersura. “Desenvolvimento da sensibilidade ao contraste de luminância espacial e temporal.” 2010. Web. 18 Jan 2021.
Vancouver:
Moreira SMCF. Desenvolvimento da sensibilidade ao contraste de luminância espacial e temporal. [Internet] [Masters thesis]. University of São Paulo; 2010. [cited 2021 Jan 18].
Available from: http://www.teses.usp.br/teses/disponiveis/47/47132/tde-21102010-110538/ ;.
Council of Science Editors:
Moreira SMCF. Desenvolvimento da sensibilidade ao contraste de luminância espacial e temporal. [Masters Thesis]. University of São Paulo; 2010. Available from: http://www.teses.usp.br/teses/disponiveis/47/47132/tde-21102010-110538/ ;
Durham University
6.
Midgley, Caroline Ann.
Binocular interactions in human vision.
Degree: PhD, 1998, Durham University
URL: http://etheses.dur.ac.uk/4839/
;
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242610
► Early visual processing is subject to binocular interactions because cells in striate cortex show binocular responses and ocular dominance (Hubel & Weisel, 1968). The work…
(more)
▼ Early visual processing is subject to binocular interactions because cells in striate cortex show binocular responses and ocular dominance (Hubel & Weisel, 1968). The work presented in this thesis suggests that these physiological interactions can be revealed in psychophysical experiments using normal human observers. In the region corresponding to the blind spot, where binocular interactions differ from areas of the visual field which are represented by two eyes, monocular contrast sensitivity is increased. This finding can be partially explained by an absence of normal binocular interactions in this location (Chapter 2). A hemianopic patient was studied in an attempt to discover whether the effect in normal observers was mediated by either a mechanism in striate cortex or via a subcortical pathway. However, the results were unable to distinguish between these two explanations (Chapter 3).In a visual search task, no difference in reaction time was observed for targets presented to the region corresponding to the blind spot compared with targets presented to adjacent binocularly represented areas of the visual field. Since performance was unaffected by the monocularity of the region corresponding to the blind, pop-out for orientation may be mediated beyond striate cortex where cells are binocularly balanced (Chapter 5). Further support for this contention was provided by studies of orientation pop-out in central vision which found that dichoptic presentation of stimuli did not affect the degree of pop-out obtained and that in general, visual search for a target based solely on eye of origin is impossible (Chapter 6). However, a task that measured orientation difference sensitivity more directly than the search experiments, found that thresholds were higher for dichoptically presented stimuli. This suggests the involvement of neurons that receive a weighted input from each eye. A model of orientation difference coding can account for the results by assuming that the range of inhibition across which orientation differences are coded is narrower for dichoptic stimuli leading to a greater resolvable orientation difference (Chapter 7).
Subjects/Keywords: 150; Blind spots; Contrast sensitivity
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APA (6th Edition):
Midgley, C. A. (1998). Binocular interactions in human vision. (Doctoral Dissertation). Durham University. Retrieved from http://etheses.dur.ac.uk/4839/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242610
Chicago Manual of Style (16th Edition):
Midgley, Caroline Ann. “Binocular interactions in human vision.” 1998. Doctoral Dissertation, Durham University. Accessed January 18, 2021.
http://etheses.dur.ac.uk/4839/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242610.
MLA Handbook (7th Edition):
Midgley, Caroline Ann. “Binocular interactions in human vision.” 1998. Web. 18 Jan 2021.
Vancouver:
Midgley CA. Binocular interactions in human vision. [Internet] [Doctoral dissertation]. Durham University; 1998. [cited 2021 Jan 18].
Available from: http://etheses.dur.ac.uk/4839/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242610.
Council of Science Editors:
Midgley CA. Binocular interactions in human vision. [Doctoral Dissertation]. Durham University; 1998. Available from: http://etheses.dur.ac.uk/4839/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242610
University of Melbourne
7.
He, Chongyue.
Illusory motion perception in migraine.
Degree: 2019, University of Melbourne
URL: http://hdl.handle.net/11343/227647
► In between attacks, people with migraine report experiencing both visual discomfort and visual illusions induced by stationary high contrast striped patterns. Since both visual illusion…
(more)
▼ In between attacks, people with migraine report experiencing both visual discomfort and visual illusions induced by stationary high contrast striped patterns. Since both visual illusion and discomfort have been assessed through largely qualitative self-report, it is unclear how their mechanisms might be related with each other. This thesis aimed to investigate whether subjective reports of visual discomfort in people with migraine are associated with the strength of a motion illusion outside attacks.
To determine the stimulus for motion illusion strength to be quantified, Experiment 1 measured the physical motion speeds that cancelled the illusory motion effect of five variants of the Fraser-Wilcox illusion in people who do not experience headache. The stimulus type that produced the most robust illusory motion was chosen for subsequent experiments.
Experiment 2 compared the motion illusion strength between people with migraine with aura, people with migraine without aura, and non-headache control participants. The relationship between motion illusion strength and self-reported frequency of experiencing visual discomfort in daily life was also investigated. The results indicated that subjective visual discomfort was elevated in people with migraine with aura but that visual discomfort was not accompanied by greater motion illusion strength. These findings suggest that susceptibility to daily visual discomfort is not related to perceived speed of the motion illusion.
Experiment 3 investigated whether motion illusion strength is associated with contrast discrimination threshold and motion sensitivity regardless of migraine status. The results revealed that people with better contrast discrimination, but not motion sensitivity, tended to perceive faster motion illusions.
The findings of this thesis verify previous self-reports of increased visual discomfort in people with migraine. The experiments, however, do not support that this self-reported experience is derived from differences in contrast discrimination or motion sensitivity, for the types of stimuli used herein. The Fraser-Wilcox motion illusion does not seem to test the same mechanisms as involved in self-reported visual discomfort.
Subjects/Keywords: migraine; motion illusion; visual discomfort; contrast discrimination; motion sensitivity
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APA (6th Edition):
He, C. (2019). Illusory motion perception in migraine. (Masters Thesis). University of Melbourne. Retrieved from http://hdl.handle.net/11343/227647
Chicago Manual of Style (16th Edition):
He, Chongyue. “Illusory motion perception in migraine.” 2019. Masters Thesis, University of Melbourne. Accessed January 18, 2021.
http://hdl.handle.net/11343/227647.
MLA Handbook (7th Edition):
He, Chongyue. “Illusory motion perception in migraine.” 2019. Web. 18 Jan 2021.
Vancouver:
He C. Illusory motion perception in migraine. [Internet] [Masters thesis]. University of Melbourne; 2019. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/11343/227647.
Council of Science Editors:
He C. Illusory motion perception in migraine. [Masters Thesis]. University of Melbourne; 2019. Available from: http://hdl.handle.net/11343/227647
University of Arizona
8.
Bontrager, Jordan G.
Characterization and Applications for A Polymerized DiaCEST Contrast Agent
.
Degree: 2015, University of Arizona
URL: http://hdl.handle.net/10150/577329
► MRI can benefit from an increase in the sensitivity of contrast agents. The CEST MRI technique in particular suffers from very poor sensitivity when using…
(more)
▼ MRI can benefit from an increase in the
sensitivity of
contrast agents. The CEST MRI technique in particular suffers from very poor
sensitivity when using diamagnetic
contrast agents. Polymerized CEST MRI
contrast agents could increase the
sensitivity per macromolecule over monomer
contrast agents. The increase in
sensitivity is related to the increase in number of
contrast agents per polymer. A
contrast agent with increased
sensitivity can be used to image on the molecular level in vivo, where the concentration of targets is very low. A polymerized diaCEST
contrast agent was synthesized by coupling a salicylic acid analogue to a poly (acrylic acid) backbone. The CEST effect of the coupled analogue was compared to its uncoupled form for different concentrations and pH values. A RL-QUEST method was used to calculate the exchange rate of the analogue for different pH values before and after coupling. The polymerized diaCEST agent was attempted to be loaded into DOPC and bis-SorbPC liposomes, and was also attempted to be targeted to folate receptors in a KB cell culture. These studies establish the foundation for translation of polymerized diaCEST
contrast agents to additional in vitro and in vivo investigations.
Advisors/Committee Members: Pagel, Mark D (advisor), Pagel, Mark D. (committeemember), Aspinwall, Craig (committeemember), Cardenas-Rodriguez, Julio (committeemember), Kuo, Phillip (committeemember).
Subjects/Keywords: diaCEST;
polymer;
QUEST;
salicylic acid;
sensitivity;
Biomedical Engineering;
contrast agent
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Manager
APA (6th Edition):
Bontrager, J. G. (2015). Characterization and Applications for A Polymerized DiaCEST Contrast Agent
. (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/577329
Chicago Manual of Style (16th Edition):
Bontrager, Jordan G. “Characterization and Applications for A Polymerized DiaCEST Contrast Agent
.” 2015. Masters Thesis, University of Arizona. Accessed January 18, 2021.
http://hdl.handle.net/10150/577329.
MLA Handbook (7th Edition):
Bontrager, Jordan G. “Characterization and Applications for A Polymerized DiaCEST Contrast Agent
.” 2015. Web. 18 Jan 2021.
Vancouver:
Bontrager JG. Characterization and Applications for A Polymerized DiaCEST Contrast Agent
. [Internet] [Masters thesis]. University of Arizona; 2015. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/10150/577329.
Council of Science Editors:
Bontrager JG. Characterization and Applications for A Polymerized DiaCEST Contrast Agent
. [Masters Thesis]. University of Arizona; 2015. Available from: http://hdl.handle.net/10150/577329
9.
Bulens, Carel.
Application of contrast sensitivity in clinical neurology.
Degree: Department of Neurology, 1988, Erasmus University Medical Center
URL: http://hdl.handle.net/1765/51052
► textabstractThis thesis is devoted to one new diagnostic technique called spatial contrast sensitivity (CS) measurement, to study visual function. This technique provides a much more…
(more)
▼ textabstractThis thesis is devoted to one new diagnostic technique called spatial contrast
sensitivity (CS) measurement, to study visual function. This technique provides
a much more comprehensive measure of visual efficiency than a standard acuity
score. The visibility of objects depends not only on their size, but also on
their relative brightness with respect to the background. Spatial contrast sensitivity
measurement takes into account the contrast necessary for an object of any
size to be detected. For its proper application in clinical neuro-ophthalmology,
knowledge about the principles underlying human spatial contrast sensitivity
is required
Subjects/Keywords: contrast; sensitivity; neurology; Parkinson's diseases
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APA (6th Edition):
Bulens, C. (1988). Application of contrast sensitivity in clinical neurology. (Doctoral Dissertation). Erasmus University Medical Center. Retrieved from http://hdl.handle.net/1765/51052
Chicago Manual of Style (16th Edition):
Bulens, Carel. “Application of contrast sensitivity in clinical neurology.” 1988. Doctoral Dissertation, Erasmus University Medical Center. Accessed January 18, 2021.
http://hdl.handle.net/1765/51052.
MLA Handbook (7th Edition):
Bulens, Carel. “Application of contrast sensitivity in clinical neurology.” 1988. Web. 18 Jan 2021.
Vancouver:
Bulens C. Application of contrast sensitivity in clinical neurology. [Internet] [Doctoral dissertation]. Erasmus University Medical Center; 1988. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/1765/51052.
Council of Science Editors:
Bulens C. Application of contrast sensitivity in clinical neurology. [Doctoral Dissertation]. Erasmus University Medical Center; 1988. Available from: http://hdl.handle.net/1765/51052
University of Georgia
10.
Engles, Michael.
Macular pigment.
Degree: 2014, University of Georgia
URL: http://hdl.handle.net/10724/24886
► The macular pigment (MP) is composed of diet-derived carotenoids that screen blue light and are concentrated in and around the fovea. Several functions for the…
(more)
▼ The macular pigment (MP) is composed of diet-derived carotenoids that screen blue light and are concentrated in and around the fovea. Several functions for the MP have been proposed. The earliest hypothesis, termed the Acuity Hypothesis,
predicts that increased MP optical density should improve spatial vision by reducing the deleterious effects of chromatic aberration, an optical phenomenon whereby short-wave light is blurred to a much greater extent than long-wave light. In light of the
fact that the atmosphere preferentially scatters short-wave light, termed blue haze, Wooten & Hammond (2002) proposed the Visibility Hypothesis. They assert that increased MP optical density should improve distance vision by selectively reducing the
veiling effects of short-wave veiling light such as “blue haze.” These two hypotheses have been tested using a specially designed optical device and a rigorous psychophysical procedure. The results do not support the Acuity Hypothesis, however our
results do support the Visibility Hypothesis. Future testing should work toward establishing a causal relation between MP optical density and CS by supplementing subjects with lutein and zeaxanthin.
Subjects/Keywords: Macular pigment; contrast sensitivity; Acuity Hypothesis; Visibility Hypothesis
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APA (6th Edition):
Engles, M. (2014). Macular pigment. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/24886
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Engles, Michael. “Macular pigment.” 2014. Thesis, University of Georgia. Accessed January 18, 2021.
http://hdl.handle.net/10724/24886.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Engles, Michael. “Macular pigment.” 2014. Web. 18 Jan 2021.
Vancouver:
Engles M. Macular pigment. [Internet] [Thesis]. University of Georgia; 2014. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/10724/24886.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Engles M. Macular pigment. [Thesis]. University of Georgia; 2014. Available from: http://hdl.handle.net/10724/24886
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of New South Wales
11.
Bodduluri, Lakshmi.
Visual functions in children with Type 1 Diabetes Mellitus.
Degree: Optometry & Vision Science, 2016, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/57111
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42537/SOURCE02?view=true
► Purpose: Type 1 diabetes mellitus (T1DM) is the most common form of DM in young populations. In adults and adolescents, DM results in diabetic retinopathy…
(more)
▼ Purpose: Type 1 diabetes mellitus (T1DM) is the most common form of DM in young populations. In adults and adolescents, DM results in diabetic retinopathy (DR), cataract and deficits in visual function (VF) and cognition. In adults, chromatic
contrast sensitivity deficits have been found to precede DR. In the earliest stages of DM, the relation between visual, ocular and cognitive health is not well understood. Advances in DM management have resulted in decreased prevalence of microvascular complications in children, allowing the investigation of the early effects of DM on their visual system. In children it is necessary to distinguish changes in VF due to T1DM from normal development. The purpose of this study was to understand any relation between visual, ocular and cognitive health of children with T1DM while accounting for normal development.Methods: Children with T1DM and controls were compared in visual, ocular (retinal thickness), and cognitive (digit symbol substitution and attentional blink) health. Visual function [chromatic (RG: red–green, BY: blue–yellow) and achromatic
contrast sensitivity] were evaluated using custom-designed games on a tablet computer in three game formats. The games were evaluated for repeatability and degree of engagement. The relation between VF, cognition and blood glucose (BG) or systemic oxygen levels (O2L), was investigated on a subset of participants over a period of one week. Patient records provided data on glycaemic control (HbA1c), age at onset and duration of DM.Results: The custom-designed games and an established test had comparable repeatability. Game 2 was the most enjoyable so was used in case-control studies. Children with T1DM had a mean ± SD age (years): 11.9 ± 1.9, duration of DM (years): 5.1 ± 3.3, HbA1c%: 8.6 ± 1.3 and no identifiable DM complications. Children with T1DM had higher BY thresholds (p=0.02). They showed greater full retinal, foveal and inner retinal thicknesses (p<0.05). There were no significant between-group differences in cognition, RG and achromatic
contrast sensitivity. Cognition was significantly related to VF (p<0.05). In children with T1DM, VF were not related to retinal thickness, BG, O2L or other DM measures.Conclusion: Despite no identified complications, children with T1DM had poorer BY
sensitivity and increased retinal thickness. These changes were not associated with other DM measures. These findings suggest that the VF deficits reflect changes in retinal physiology.
Advisors/Committee Members: Boon, Mei Ying, Optometry & Vision Science, Faculty of Science, UNSW, Dain, Stephen, Optometry & Vision Science, Faculty of Science, UNSW.
Subjects/Keywords: Chromatic contrast sensitivity; Type 1 diabetes mellitus; Colour vision; Retinal thickness
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APA (6th Edition):
Bodduluri, L. (2016). Visual functions in children with Type 1 Diabetes Mellitus. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/57111 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42537/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Bodduluri, Lakshmi. “Visual functions in children with Type 1 Diabetes Mellitus.” 2016. Doctoral Dissertation, University of New South Wales. Accessed January 18, 2021.
http://handle.unsw.edu.au/1959.4/57111 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42537/SOURCE02?view=true.
MLA Handbook (7th Edition):
Bodduluri, Lakshmi. “Visual functions in children with Type 1 Diabetes Mellitus.” 2016. Web. 18 Jan 2021.
Vancouver:
Bodduluri L. Visual functions in children with Type 1 Diabetes Mellitus. [Internet] [Doctoral dissertation]. University of New South Wales; 2016. [cited 2021 Jan 18].
Available from: http://handle.unsw.edu.au/1959.4/57111 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42537/SOURCE02?view=true.
Council of Science Editors:
Bodduluri L. Visual functions in children with Type 1 Diabetes Mellitus. [Doctoral Dissertation]. University of New South Wales; 2016. Available from: http://handle.unsw.edu.au/1959.4/57111 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42537/SOURCE02?view=true
The Ohio State University
12.
Njeru, Steve Murimi Mathenge.
Contrast Sensitivity and Visual Acuity in Low-Vision
Students.
Degree: MS, Vision Science, 2020, The Ohio State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1586966057072378
► Purpose: This study primarily compared the test-retest reliability of the Pelli-Robson chart (PR) and Ohio Contrast Cards (OCC) amongst testers. The secondary goal of this…
(more)
▼ Purpose: This study primarily compared the test-retest
reliability of the Pelli-Robson chart (PR) and Ohio
Contrast Cards
(OCC) amongst testers. The secondary goal of this study was to
examine the impact on
contrast sensitivity if the testing distance
for the Pelli-Robson chart were to be changed. An additional goal
was to evaluate the relationship between visual acuity (VA) and
contrast sensitivity (CS) when using letter-based charts and
grating cards. Methods: Thirty low-vision students were tested,
ranging from 7-20 years old. Each student was tested with both VA
and CS tests in randomized order, which included: the Bailey-Lovie
chart (BL), Pelli-Robson chart, Teller Acuity Cards (TAC), and Ohio
Contrast Cards. Each student repeated both the PR chart and OCC in
separate rooms, but neither the BL chart nor TAC was repeated. The
PR chart was also tested at closer testing distance, based on the
student’s logMAR acuity from the BL chart. For the letter charts, a
letter-by-letter scoring method was used. For grating cards, these
were both scored as preferential looking tests. Results: The Limits
of Agreement for the OCC and PR chart were +/- 0.451 and +/- 0.536,
respectively. There was no statistically significant difference
between tester or order of testers for the PR chart and OCC. Using
the PR chart at a closer distance yielded an improvement in
contrast threshold performance when compared to the standard
testing distance. Students performed better on grating cards than
letter charts, regardless of VA testing or CS testing. Conclusions:
The Ohio
Contrast Cards are a promising diagnostic tool for
evaluating CS on low-vision patients and other patients who cannot
be tested using letter-based charts. Clinicians using the
Pelli-Robson chart for low-vision patients should consider testing
closer than the standard testing distance.
Advisors/Committee Members: Brown, Angela (Advisor).
Subjects/Keywords: Health Care; Ophthalmology; contrast sensitivity, visual acuity, low-vision
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APA (6th Edition):
Njeru, S. M. M. (2020). Contrast Sensitivity and Visual Acuity in Low-Vision
Students. (Masters Thesis). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1586966057072378
Chicago Manual of Style (16th Edition):
Njeru, Steve Murimi Mathenge. “Contrast Sensitivity and Visual Acuity in Low-Vision
Students.” 2020. Masters Thesis, The Ohio State University. Accessed January 18, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1586966057072378.
MLA Handbook (7th Edition):
Njeru, Steve Murimi Mathenge. “Contrast Sensitivity and Visual Acuity in Low-Vision
Students.” 2020. Web. 18 Jan 2021.
Vancouver:
Njeru SMM. Contrast Sensitivity and Visual Acuity in Low-Vision
Students. [Internet] [Masters thesis]. The Ohio State University; 2020. [cited 2021 Jan 18].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1586966057072378.
Council of Science Editors:
Njeru SMM. Contrast Sensitivity and Visual Acuity in Low-Vision
Students. [Masters Thesis]. The Ohio State University; 2020. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1586966057072378
Northeastern University
13.
Lei, Quan.
When the weaker conquer: a contrast-based illusion of visual numerosity and its dependence on segregation.
Degree: PhD, Department of Psychology, 2015, Northeastern University
URL: http://hdl.handle.net/2047/D20195163
► Humans and many non-human species alike are endowed with a capability to perceive the approximate numerosity of a large set. In the visual domain, various…
(more)
▼ Humans and many non-human species alike are endowed with a capability to perceive the approximate numerosity of a large set. In the visual domain, various factors have been found to affect perceived numerosity. These include continuous extent variables (i.e., length, area, density, etc.), spatial structure of the stimulus (e.g. clustering) and visual contexts. In the current study, the effect of luminance contrast on approximate numerosity perception was investigated.
Subjects/Keywords: contrast; illusion; segregation; thresholding hypothesis; visual numerosity; Visual perception; Testing; Contrast sensitivity (Vision); Optical illusions; Number concept
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APA (6th Edition):
Lei, Q. (2015). When the weaker conquer: a contrast-based illusion of visual numerosity and its dependence on segregation. (Doctoral Dissertation). Northeastern University. Retrieved from http://hdl.handle.net/2047/D20195163
Chicago Manual of Style (16th Edition):
Lei, Quan. “When the weaker conquer: a contrast-based illusion of visual numerosity and its dependence on segregation.” 2015. Doctoral Dissertation, Northeastern University. Accessed January 18, 2021.
http://hdl.handle.net/2047/D20195163.
MLA Handbook (7th Edition):
Lei, Quan. “When the weaker conquer: a contrast-based illusion of visual numerosity and its dependence on segregation.” 2015. Web. 18 Jan 2021.
Vancouver:
Lei Q. When the weaker conquer: a contrast-based illusion of visual numerosity and its dependence on segregation. [Internet] [Doctoral dissertation]. Northeastern University; 2015. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/2047/D20195163.
Council of Science Editors:
Lei Q. When the weaker conquer: a contrast-based illusion of visual numerosity and its dependence on segregation. [Doctoral Dissertation]. Northeastern University; 2015. Available from: http://hdl.handle.net/2047/D20195163
Queensland University of Technology
14.
Kimlin, Janessa A.
Night driving and assessment of mesopic vision for older adults.
Degree: 2016, Queensland University of Technology
URL: https://eprints.qut.edu.au/101497/
► For many older adults, night driving is difficult due to age-related changes affecting vision under low light and glare conditions. However, there is a lack…
(more)
▼ For many older adults, night driving is difficult due to age-related changes affecting vision under low light and glare conditions. However, there is a lack of evidence for healthcare practitioners to base their advice to patients about visual fitness to drive safely at night. This research investigated the relationships between self-reported vision-related night driving difficulties, visual function tests and night driving performance. It was found that vision tests conducted under lower light levels, similar to the night driving environment, were important for predicting poorer night driving performance and for assessing drivers reporting high levels of vision-related night driving difficulties.
Subjects/Keywords: mesopic; night driving; motion sensitivity; mesotest; contrast sensitivity; visual acuity; disability glare; questionnaire; ageing; Rasch analysis
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APA (6th Edition):
Kimlin, J. A. (2016). Night driving and assessment of mesopic vision for older adults. (Thesis). Queensland University of Technology. Retrieved from https://eprints.qut.edu.au/101497/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kimlin, Janessa A. “Night driving and assessment of mesopic vision for older adults.” 2016. Thesis, Queensland University of Technology. Accessed January 18, 2021.
https://eprints.qut.edu.au/101497/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kimlin, Janessa A. “Night driving and assessment of mesopic vision for older adults.” 2016. Web. 18 Jan 2021.
Vancouver:
Kimlin JA. Night driving and assessment of mesopic vision for older adults. [Internet] [Thesis]. Queensland University of Technology; 2016. [cited 2021 Jan 18].
Available from: https://eprints.qut.edu.au/101497/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kimlin JA. Night driving and assessment of mesopic vision for older adults. [Thesis]. Queensland University of Technology; 2016. Available from: https://eprints.qut.edu.au/101497/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
15.
Nogueira, Renata Maria Toscano Barreto Lyra.
Percepção visual de contraste em portadores de esquizofrenia e parentes não acometidos.
Degree: PhD, Neurociências e Comportamento, 2010, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/47/47135/tde-30072010-103810/
;
► A esquizofrenia é um distúrbio mental debilitante que afeta aproximadamente 1% da população mundial, caracterizado por sintomas produtivos como delírios e alucinações e sintomas negativos…
(more)
▼ A esquizofrenia é um distúrbio mental debilitante que afeta aproximadamente 1% da população mundial, caracterizado por sintomas produtivos como delírios e alucinações e sintomas negativos como apatia e decréscimo das emoções. O objetivo deste trabalho foi caracterizar a resposta do sistema visual humano de voluntários isentos de transtornos neuropsiquiátricos, portadores de esquizofrenia medicados e parentes não acometidos, utilizando a curva de sensibilidade ao contraste (FSC) escotópica e fotópica para estímulos de frequências espaciais com grades senoidais verticais e com grade senoidais angulares. As medidas de limiares ou sensibilidades ao contraste para grades senoidais verticais com frequências espaciais de 0,25; 2; 4 e 8 ciclos por grau de ângulo visual (cpg) e para grades senoidais angulares definidos com frequências espaciais de 3,0; 24; 48 e 96 ciclos/360° foram medidas com o método psicofísico da escolha forçada entre duas alternativas temporais. Os resultados mostram que os portadores de esquizofrenia apresentam prejuízo para os estímulos espaciais de grade senoidal vertical e angular em todas as frequências testadas e nas duas condições de luminância enquanto que os parentes não psicóticos apresentaram a sensibilidade ao contraste preservada para os dois estímulos nas duas condições de luminância. Estes dados sugerem prejuízos no processamento visual de contraste associados à esquizofrenia, sugerindo que esse transtorno altera as áreas visuais corticais de forma difusa.
Schizophrenia is a mental debilitating disorder that affects 1% of the world population. It is characterized by positive symptoms such as delirium and hallucinations and negative symptoms such as apathy and emotion decrease. The objective of this work was to characterize the response of the human visual system to vertical and angular sine-wave gratings in healthy adults (20-45 years of age), schizophrenia patients whom were receiving antipsychotic medications and unaffected relatives of schizophrenia patients. We measured the contrast sensitivity functions for vertical sine-wave gratings of 0.25, 1, 2 and 8 cycles per degree (cpd) of visual angle and angular sine-wave gratings of 3, 24, 48 and 96 cycle/360o Contrast threshold was measured using a temporal two-alternative forced choice (2-AFC) procedure with mean scotopic luminance of 0.06 cd/m2 and mean photopic luminance of 42 cd/m2. The results showed a decrease in sensitivity of schizophrenia patients to all the stimuli of vertical and angular sine-wave grating at all spatial frequencies and to the two luminance conditions, while the non-psychotic relatives showed preserved contrast sensitivity for the two stimuli in both luminance conditions. These data suggest that losses in the visual processing of contrast associated with schizophrenia, suggesting that this disorder alters the cortical visual areas in a diffuse way.
Advisors/Committee Members: Britto, Luiz Roberto Giorgetti de.
Subjects/Keywords: Contrast sensitivity; Esquizofrênia; Percepção visual; Schizophrenia; Sensibilidade de constraste visual; Visual perception
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APA (6th Edition):
Nogueira, R. M. T. B. L. (2010). Percepção visual de contraste em portadores de esquizofrenia e parentes não acometidos. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/47/47135/tde-30072010-103810/ ;
Chicago Manual of Style (16th Edition):
Nogueira, Renata Maria Toscano Barreto Lyra. “Percepção visual de contraste em portadores de esquizofrenia e parentes não acometidos.” 2010. Doctoral Dissertation, University of São Paulo. Accessed January 18, 2021.
http://www.teses.usp.br/teses/disponiveis/47/47135/tde-30072010-103810/ ;.
MLA Handbook (7th Edition):
Nogueira, Renata Maria Toscano Barreto Lyra. “Percepção visual de contraste em portadores de esquizofrenia e parentes não acometidos.” 2010. Web. 18 Jan 2021.
Vancouver:
Nogueira RMTBL. Percepção visual de contraste em portadores de esquizofrenia e parentes não acometidos. [Internet] [Doctoral dissertation]. University of São Paulo; 2010. [cited 2021 Jan 18].
Available from: http://www.teses.usp.br/teses/disponiveis/47/47135/tde-30072010-103810/ ;.
Council of Science Editors:
Nogueira RMTBL. Percepção visual de contraste em portadores de esquizofrenia e parentes não acometidos. [Doctoral Dissertation]. University of São Paulo; 2010. Available from: http://www.teses.usp.br/teses/disponiveis/47/47135/tde-30072010-103810/ ;
16.
Alencar, Caroline Dias da Costa.
Efeitos da desnutrição proteica na percepção de contraste e acuidade visual em humanos e em ratos.
Degree: PhD, Neurociências e Comportamento, 2014, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/47/47135/tde-17032015-124043/
;
► O objetivo do presente estudo foi avaliar o efeito da desnutrição proteica em humanos e em modelo animal por meio de medidas comportamentais e bioquímicas.…
(more)
▼ O objetivo do presente estudo foi avaliar o efeito da desnutrição proteica em humanos e em modelo animal por meio de medidas comportamentais e bioquímicas. Participaram desse estudo 60 crianças com idade de 7 a 10 anos, sendo 20 eutróficas (grupo controle, GC), 20 com desnutrição atual (grupo experimental atual, GEa) e 20 com desnutrição pregressa (grupo experimental pregresso, GEp). Esses três grupos foram replicados em modelo animal, sendo cada grupo composto por 6 ratos wistar. A acuidade visual (AV) e a sensibilidade ao contraste (SC) foram medidas por meio do método psicofísico em humanos (experimento I) e em ratos (experimento II). Para a medida comportamental com animais foi desenvolvido o Labirinto de Imagens. As análises bioquímicas foram realizadas por meio da técnica de imunohistoquímica e de morfometria da retina de 5 animais de cada grupo (experimento III). Os resultados dos testes comportamentais em humanos e em animais mostraram prejuízos no desempenho dos grupos desnutridos, principalmente no GEp, mesmo com recuperação nutricional. O Labirinto de Imagens se mostrou uma ferramenta útil para medida de parâmetros visuais em roedores. Entretanto, as análises histológicas não apresentaram diferenças significantes entre os grupos, o que provavelmente se deve ao nível de análise não ser capaz de medir componentes sinápticos, arborização dendrítica ou do sistema de neurotransmissão
Not informed by the author
Advisors/Committee Members: Almeida, Sebastião de Sousa, Britto, Luiz Roberto Giorgetti de.
Subjects/Keywords: Acuidade visual; Contrast sensitivity; Desnutrição; Nutricional deficiencies; Psicofísica; Psychophysics; Sensibilidade ao contraste; Visual acuity
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APA (6th Edition):
Alencar, C. D. d. C. (2014). Efeitos da desnutrição proteica na percepção de contraste e acuidade visual em humanos e em ratos. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/47/47135/tde-17032015-124043/ ;
Chicago Manual of Style (16th Edition):
Alencar, Caroline Dias da Costa. “Efeitos da desnutrição proteica na percepção de contraste e acuidade visual em humanos e em ratos.” 2014. Doctoral Dissertation, University of São Paulo. Accessed January 18, 2021.
http://www.teses.usp.br/teses/disponiveis/47/47135/tde-17032015-124043/ ;.
MLA Handbook (7th Edition):
Alencar, Caroline Dias da Costa. “Efeitos da desnutrição proteica na percepção de contraste e acuidade visual em humanos e em ratos.” 2014. Web. 18 Jan 2021.
Vancouver:
Alencar CDdC. Efeitos da desnutrição proteica na percepção de contraste e acuidade visual em humanos e em ratos. [Internet] [Doctoral dissertation]. University of São Paulo; 2014. [cited 2021 Jan 18].
Available from: http://www.teses.usp.br/teses/disponiveis/47/47135/tde-17032015-124043/ ;.
Council of Science Editors:
Alencar CDdC. Efeitos da desnutrição proteica na percepção de contraste e acuidade visual em humanos e em ratos. [Doctoral Dissertation]. University of São Paulo; 2014. Available from: http://www.teses.usp.br/teses/disponiveis/47/47135/tde-17032015-124043/ ;
Northeastern University
17.
Shepard, Timothy G.
Detection, color matching, and discrimination: an exploration of the nature and number of chromatic mechanisms.
Degree: PhD, Department of Psychology, 2016, Northeastern University
URL: http://hdl.handle.net/2047/D20214830
► Narrowly-tuned, selective noise masking of chromatic detection has been taken as evidence for the existence of "higher-order" color mechanisms. Experiment 1 replicates earlier observations of…
(more)
▼ Narrowly-tuned, selective noise masking of chromatic detection has been taken as evidence for the existence of "higher-order" color mechanisms. Experiment 1 replicates earlier observations of selective masking of tests in the (L, M) plane of cone space when the noise is placed near the corners of the detection contour. We used unipolar Gaussian blob tests, with three different noise color directions, and show that there are substantial asymmetries in the detection contours, asymmetries that would have been missed with bipolar tests such as Gabor patches. A new chromatic detection model, which is based upon probability summation of linear cone combinations, incorporates a linear contrast energy vs. noise power relationship that predicts how the sensitivity of these mechanisms changes with noise contrast and chromaticity is presented. With only six unipolar color mechanisms - the same number as the cardinal model - the new model accounts for the threshold contours across the different noise conditions, including the asymmetries and the selective effects of the noises. Our model is different from the cardinal model, in at least one important way. Four of the six detection mechanisms here have opposed L and M cone inputs and that is the feature that allows it to predict selective masking across noise conditions without a large number of mechanisms.; In Experiment 2, results of asymmetric color matching of the threshold-level tests from Experiment 1 were used to test the detection model. The assumption is that the mechanisms are univariant labelled lines (Rushton, 1972; Watson & Robson, 1981), implying here that the colors of physically-different stimuli that are detected by a single mechanism should all be the same, and suggesting that the colors of two stimuli detected by different mechanisms should differ. Physically different stimuli that lie along one mechanism threshold line should therefore produce metameric color matches - post-receptoral metamers - while tests that lie on two different mechanism lines should be matched with different colors. The results show that color matches fall into six clusters in CIE (u', v') space (across all the noise conditions), and these clusters correspond closely to the six mechanisms in the model. Most importantly, where the detection model determines that a given test angle is detected by different mechanisms in different noise conditions (due to differential masking), the hue of that test angle changes in a consistent way. These color matches essentially apply a color label to each of the mechanism threshold lines, confirm the six-mechanism model, and quantify the hue signaled by each mechanism.; In a discrimination experiment (Experiment 3), on a given trial, two threshold-level stimuli (one "standard" and one "test") were presented in random order, and observers were asked to select the standard. Across trials, many different standards and tests in the (L,M) plane of cone contrast space were used, with and without chromatic masking noise (Shepard et. al., 2016). …
Subjects/Keywords: chromatic detection; Visual perception; Color vision; Contrast sensitivity (Vision); Psychophysics; Algebras, Linear
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APA (6th Edition):
Shepard, T. G. (2016). Detection, color matching, and discrimination: an exploration of the nature and number of chromatic mechanisms. (Doctoral Dissertation). Northeastern University. Retrieved from http://hdl.handle.net/2047/D20214830
Chicago Manual of Style (16th Edition):
Shepard, Timothy G. “Detection, color matching, and discrimination: an exploration of the nature and number of chromatic mechanisms.” 2016. Doctoral Dissertation, Northeastern University. Accessed January 18, 2021.
http://hdl.handle.net/2047/D20214830.
MLA Handbook (7th Edition):
Shepard, Timothy G. “Detection, color matching, and discrimination: an exploration of the nature and number of chromatic mechanisms.” 2016. Web. 18 Jan 2021.
Vancouver:
Shepard TG. Detection, color matching, and discrimination: an exploration of the nature and number of chromatic mechanisms. [Internet] [Doctoral dissertation]. Northeastern University; 2016. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/2047/D20214830.
Council of Science Editors:
Shepard TG. Detection, color matching, and discrimination: an exploration of the nature and number of chromatic mechanisms. [Doctoral Dissertation]. Northeastern University; 2016. Available from: http://hdl.handle.net/2047/D20214830
University of Illinois – Chicago
18.
Hall, Cierra Michelle.
A Luminance Noise Approach to Target Post-Receptor Visual Pathways; Application to Optic Nerve Disease.
Degree: 2016, University of Illinois – Chicago
URL: http://hdl.handle.net/10027/21610
► Contrast sensitivity (CS), which is the ability to detect small differences in luminance, is a fundamental task of the visual system and loss of CS…
(more)
▼ Contrast sensitivity (CS), which is the ability to detect small differences in luminance, is a fundamental task of the visual system and loss of CS is an important marker for many disease states. Although clinically-applicable methods are available to assess CS, there are limitations to these standard methods. For example, they are unable to determine which of the two primary post-receptor visual pathways, the magnocellular (MC) and parvocellular (PC) pathways, mediates CS for a given task. Furthermore, standard clinical measures of CS cannot provide insight into mechanisms underlying CS abnormalities.
In this thesis, a test of CS using letter stimuli will be developed and applied to address these issues. To permit the development of this new CS test, the following series of questions will first be resolved and an optimized CS test will then be applied to patients who have optic nerve dysfunction to better understand their CS deficits. Question 1: Which optotypes should be used in tests of letter CS? Letters are relatively complex targets that are not all equally identifiable. Aim 1 will define the optimal letter set for use in CS testing. Question 2: Can luminance noise, defined as decrements and increments of luminance added to a stimulus (e.g. ‘tv snow’), be used to target the MC and PC pathways? Although there is preliminary evidence that the temporal characteristics of noise can be manipulated to target these post receptor pathways selectively, the specific characteristics of noise needed to do so have not been fully defined. Aim 2 will determine the spatial and temporal characteristics of noise capable of targeting the MC and PC pathways. Question 3: What is the optimal letter size for use in targeting the MC and PC pathways using static and dynamic luminance noise? Aim 3 will determine the range of letter sizes that can be used to target selectively the MC and PC pathways. Question 4: What is the optimal letter duration for use in targeting the MC and PC pathways in noise-based CS tests? Aim 4 will evaluate the ability of static and dynamic noise to target the MC and PC pathways across a series of letter exposure durations. Once the test is developed and finalized, it will be applied in Aim 5 to a small sample of patients who have optic neuritis (ON); the results from the patients will be compared to visually-normal control subjects.
Thus, this dissertation will develop a clinically applicable, noise-based test of letter CS that can independently assess function within the MC and PC pathways. This will permit evaluating potential deficits within the MC and PC pathways, as well as provide preliminary insight into potential factors that limit CS in patients who have ON.
Advisors/Committee Members: McAnany, J. Jason (advisor), Patton, James (committee member), Hetling, John (committee member), Cao, Dingcai (committee member), Royston, Thomas (chair).
Subjects/Keywords: luminance noise; contrast sensitivity; magnocellular pathway; parvocellular pathway; optic neuritis; internal noise; efficiency; object frequency
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APA (6th Edition):
Hall, C. M. (2016). A Luminance Noise Approach to Target Post-Receptor Visual Pathways; Application to Optic Nerve Disease. (Thesis). University of Illinois – Chicago. Retrieved from http://hdl.handle.net/10027/21610
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Hall, Cierra Michelle. “A Luminance Noise Approach to Target Post-Receptor Visual Pathways; Application to Optic Nerve Disease.” 2016. Thesis, University of Illinois – Chicago. Accessed January 18, 2021.
http://hdl.handle.net/10027/21610.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Hall, Cierra Michelle. “A Luminance Noise Approach to Target Post-Receptor Visual Pathways; Application to Optic Nerve Disease.” 2016. Web. 18 Jan 2021.
Vancouver:
Hall CM. A Luminance Noise Approach to Target Post-Receptor Visual Pathways; Application to Optic Nerve Disease. [Internet] [Thesis]. University of Illinois – Chicago; 2016. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/10027/21610.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Hall CM. A Luminance Noise Approach to Target Post-Receptor Visual Pathways; Application to Optic Nerve Disease. [Thesis]. University of Illinois – Chicago; 2016. Available from: http://hdl.handle.net/10027/21610
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
19.
Khalil, Nofal Mohammed.
Investigations of visual function in migraine by visual evoked potentials and visual psychophysical tests.
Degree: PhD, 1991, Imperial College London
URL: http://hdl.handle.net/10044/1/8336
Subjects/Keywords: 610; Visual illusions; Spatial contrast sensitivity
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APA (6th Edition):
Khalil, N. M. (1991). Investigations of visual function in migraine by visual evoked potentials and visual psychophysical tests. (Doctoral Dissertation). Imperial College London. Retrieved from http://hdl.handle.net/10044/1/8336
Chicago Manual of Style (16th Edition):
Khalil, Nofal Mohammed. “Investigations of visual function in migraine by visual evoked potentials and visual psychophysical tests.” 1991. Doctoral Dissertation, Imperial College London. Accessed January 18, 2021.
http://hdl.handle.net/10044/1/8336.
MLA Handbook (7th Edition):
Khalil, Nofal Mohammed. “Investigations of visual function in migraine by visual evoked potentials and visual psychophysical tests.” 1991. Web. 18 Jan 2021.
Vancouver:
Khalil NM. Investigations of visual function in migraine by visual evoked potentials and visual psychophysical tests. [Internet] [Doctoral dissertation]. Imperial College London; 1991. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/10044/1/8336.
Council of Science Editors:
Khalil NM. Investigations of visual function in migraine by visual evoked potentials and visual psychophysical tests. [Doctoral Dissertation]. Imperial College London; 1991. Available from: http://hdl.handle.net/10044/1/8336
University of Melbourne
20.
Hackett, Deborah Anne.
Exploring the mechanisms of Rarebit perimetry.
Degree: 2009, University of Melbourne
URL: http://hdl.handle.net/11343/35202
► Visual field testing, or perimetry, measures peripheral visual loss in eye diseases such as glaucoma. Rarebit Perimetry (RBP) is a new and novel perimetric method,…
(more)
▼ Visual field testing, or perimetry, measures peripheral visual loss in eye diseases such as glaucoma. Rarebit Perimetry (RBP) is a new and novel perimetric method, introduced in 2002 by Lars Frisén (2002), with the aim of detecting low degrees of neural damage within the retina.
RBP is unlike conventional perimetric methods that measure levels of retinal sensitivity, but instead uses very bright (i.e. suprathreshold) and very small targets to detect tiny areas of absolute blindness within otherwise normal areas of vision. RBP thus claims to locate miniscule gaps in the receptive field matrix of neurons in the retina, with the assumption that dead neurons leave gaps in this matrix. The most useful application of this idea is to detect progressive eye disease in the earliest stages (Frisén, 2002). Current research shows that RBP correlates with other standard visual field tests (Brusini, Salvetat, et al., 2005; Frisén, 2003; Gedik, Akman, et al., 2007; Martin & Wanger, 2004), but may afford greater sensitivity by detecting very mild visual losses missed by other tests (Martin, Ley, et al., 2004; Martin & Nilsson, 2007; Nilsson, Wendt, et al., 2007).
To date, there are no studies that definitively test the theoretical basis of RBP, so in this thesis I aim to explore the proposed underlying mechanisms and assumptions of this test. In particular, the proposed mechanism of RBP leads to specific predictions as to how responses will alter when the luminances of the RBP targets are systematically decreased. I therefore compared RBP responses of mean hit rate as a function of target luminance and found results to be inconsistent with the proposed RBP mechanism. Mathematical simulations were performed to explore reasons for the differences between the two groups (Chapter Seven).
Subjects/Keywords: Rarebit; perimetry; contrast sensitivity; threshold; glaucoma
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APA (6th Edition):
Hackett, D. A. (2009). Exploring the mechanisms of Rarebit perimetry. (Masters Thesis). University of Melbourne. Retrieved from http://hdl.handle.net/11343/35202
Chicago Manual of Style (16th Edition):
Hackett, Deborah Anne. “Exploring the mechanisms of Rarebit perimetry.” 2009. Masters Thesis, University of Melbourne. Accessed January 18, 2021.
http://hdl.handle.net/11343/35202.
MLA Handbook (7th Edition):
Hackett, Deborah Anne. “Exploring the mechanisms of Rarebit perimetry.” 2009. Web. 18 Jan 2021.
Vancouver:
Hackett DA. Exploring the mechanisms of Rarebit perimetry. [Internet] [Masters thesis]. University of Melbourne; 2009. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/11343/35202.
Council of Science Editors:
Hackett DA. Exploring the mechanisms of Rarebit perimetry. [Masters Thesis]. University of Melbourne; 2009. Available from: http://hdl.handle.net/11343/35202
University of Central Florida
21.
Zavod, Merrill.
The Effects Of Stimulus Motion On Contrast Sensitivity: Dynamic Sensi.
Degree: 2004, University of Central Florida
URL: https://stars.library.ucf.edu/etd/267
► Static Visual Acuity (SVA) has been called into question for some time as a measure of overall visual system function and as a predictor of…
(more)
▼ Static Visual Acuity (SVA) has been called into question for some time as a measure of overall visual system function and as a predictor of performance on real-life tasks requiring vision (i.e., operating an automobile). Specifically, it has been pointed out that the targets employed in most SVA testing (high
contrast, stationary letters) are an insufficient analog to actual targets encountered in everyday activities, which are often in motion and/or of less-than-perfect
contrast. In addition, the size-threshold methodology typically used to measure SVA is incongruent with current theories of a multi-channel visual system. Dynamic Visual Acuity (DVA) and
Contrast Sensitivity have been suggested as alternatives to SVA, but while each mitigates specific weaknesses of the SVA measure, neither addresses the shortcomings completely. Traditional DVA measures employ moving targets, but these targets are usually of perfect
contrast and a size-threshold methodology is used to specify acuity levels.
Contrast Sensitivity employs a
contrast-threshold methodology and allows measurement of specific visual channels, but stationary targets are utilized. The present study combined the DVA and
Contrast Sensitivity measures in an effort to retain the unique qualities of each while addressing their shortcomings, resulting in a more detailed picture of the human visual system and functioning than has yet been possible. By measuring
contrast sensitivity to targets at a set of spatial frequencies spanning the human "window of visibility" and under conditions of motion representative of that encountered in everyday activities, it was hoped that a more powerful predictor of actual visual performance would be created. In addition, normative data was established for two separate age populations, in the hopes of learning more about specific changes that occur to the visual system during the aging process. Indeed, several effects and interactions among the three main variables (spatial frequency, velocity, age) were uncovered, which appears to indicate that the new test may provide more information about the visual system than DVA or
contrast sensitivity by themselves. The ramifications of this effort to human factors and visual performance research are discussed along with recommendations for the continuation and application of this line of research.
Advisors/Committee Members: Rinalducci, Edward.
Subjects/Keywords: Dynamic Visual Acuity; Contrast Sensitivity; Psychology
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APA ·
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APA (6th Edition):
Zavod, M. (2004). The Effects Of Stimulus Motion On Contrast Sensitivity: Dynamic Sensi. (Doctoral Dissertation). University of Central Florida. Retrieved from https://stars.library.ucf.edu/etd/267
Chicago Manual of Style (16th Edition):
Zavod, Merrill. “The Effects Of Stimulus Motion On Contrast Sensitivity: Dynamic Sensi.” 2004. Doctoral Dissertation, University of Central Florida. Accessed January 18, 2021.
https://stars.library.ucf.edu/etd/267.
MLA Handbook (7th Edition):
Zavod, Merrill. “The Effects Of Stimulus Motion On Contrast Sensitivity: Dynamic Sensi.” 2004. Web. 18 Jan 2021.
Vancouver:
Zavod M. The Effects Of Stimulus Motion On Contrast Sensitivity: Dynamic Sensi. [Internet] [Doctoral dissertation]. University of Central Florida; 2004. [cited 2021 Jan 18].
Available from: https://stars.library.ucf.edu/etd/267.
Council of Science Editors:
Zavod M. The Effects Of Stimulus Motion On Contrast Sensitivity: Dynamic Sensi. [Doctoral Dissertation]. University of Central Florida; 2004. Available from: https://stars.library.ucf.edu/etd/267
University of New South Wales
22.
Jimenez Barbosa, Ingrid Astrid.
VISUAL FUNCTION IN DRY CLEANERS.
Degree: Optometry & Vision Science, 2014, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/53436
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12131/SOURCE02?view=true
► Exposure to Organic Solvents (OS) used in the dry cleaning industry (DCI), has been found to be associated with neurotoxicity and changes in colour vision…
(more)
▼ Exposure to Organic Solvents (OS) used in the dry cleaning industry (DCI), has been found to be associated with neurotoxicity and changes in colour vision (CV) and
contrast sensitivity (CS). The purpose of this thesis is to investigate whether the degree to which exposure to occupational levels of organic solvents (OS) in the dry cleaning industry is associated with neurotoxic symptoms and low and high level visual and cognitive functions. To address this issue a series of comprehensive studies were conducted to examine the impact of exposure to OS in both low level (
contrast and colour vision) and high level visual functions (global motion, global form perception) also visual cognitive changes (visual search).The study was conducted in two populations in Colombia and Australia at risk of exposure to OS used in the DCI, but have different regulations for exposure. The range of duration of occupational exposure to OS of the participants was from 1-15 years. Control groups of people with community levels of exposure to OS used in DCI were also assessed in both countries (n=35 each site). Visual function measures assessed were CS, CV using the Farnsworth 100 Hue error score, Visual Search (VS), Glass Pattern Perception (GPP) and Global Motion Perception (GMP). Neurotoxic symptoms were assessed using the World Health Organization recommended questionnaire, the Q16, in its original form and a Likert scale modified version. Major results were that dry cleaners had poorer CS (extending to lower spatial frequencies than reported previously), hue discrimination, deficits in form and motion detection (decreased GPP and, GMS
sensitivity) and higher Q16 scores than non-dry cleaners (p<0.05) for both countries. Visual search was unaffected in drycleaners and non- drycleaners in both countries suggesting that OS used in the DCI affect lower order VF but not higher-level cognition. There was no beneficial effect of specific regulations to OS exposure to DCI. Within drycleaners, severity of neurotoxicity symptoms and deficits in both low and high level visual functions were unrelated to exposure durations experience by the sample suggesting that the effects occur even with short exposures. The low and high level visual function measures had greater
sensitivity and specificity in distinguishing between drycleaners exposed to OS used in the DCI and people with only community levels of exposure.
Advisors/Committee Members: Khuu, Sieu, Optometry & Vision Science, Faculty of Science, UNSW, Boon, Mei-Ying, Optometry & Vision Science, Faculty of Science, UNSW.
Subjects/Keywords: Neurotoxicity; Organic Solvents; Visual Function; Contrast Sensitivity; Colour vision; Form perception; Global dot motion perception
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APA (6th Edition):
Jimenez Barbosa, I. A. (2014). VISUAL FUNCTION IN DRY CLEANERS. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/53436 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12131/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Jimenez Barbosa, Ingrid Astrid. “VISUAL FUNCTION IN DRY CLEANERS.” 2014. Doctoral Dissertation, University of New South Wales. Accessed January 18, 2021.
http://handle.unsw.edu.au/1959.4/53436 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12131/SOURCE02?view=true.
MLA Handbook (7th Edition):
Jimenez Barbosa, Ingrid Astrid. “VISUAL FUNCTION IN DRY CLEANERS.” 2014. Web. 18 Jan 2021.
Vancouver:
Jimenez Barbosa IA. VISUAL FUNCTION IN DRY CLEANERS. [Internet] [Doctoral dissertation]. University of New South Wales; 2014. [cited 2021 Jan 18].
Available from: http://handle.unsw.edu.au/1959.4/53436 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12131/SOURCE02?view=true.
Council of Science Editors:
Jimenez Barbosa IA. VISUAL FUNCTION IN DRY CLEANERS. [Doctoral Dissertation]. University of New South Wales; 2014. Available from: http://handle.unsw.edu.au/1959.4/53436 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12131/SOURCE02?view=true
23.
Ketomäki, Jaakko.
Effects of Lighting Parameters on Contrast Threshold in the Mesopic and Photopic Luminance Ranges.
Degree: 2006, Helsinki University of Technology
URL: http://lib.tkk.fi/Diss/2006/isbn9512283344/
► The first objective of this thesis was to find out how the background luminance level, spectra of the background and stimulus, and eccentricity of the…
(more)
▼ The first objective of this thesis was to find out how the background luminance level, spectra of the background and stimulus, and eccentricity of the stimulus affect contrast thresholds in the mesopic luminance range. The background luminance levels used were between LB=0.01…20 cd/m2. They cover the typical luminance levels of road lighting. The spectra of the background and stimulus were broadband white, blue, green, and red. The measurements were made at eccentricities of 0 and 10°. The results of this thesis confirmed that when the photopic background luminance level decreases from LB=10 cd/m2 to LB=0.01 cd/m2 the contrast threshold increases at stimulus eccentricities of both 0 and 10°. It was found that the contrast threshold increased the least with blue and the most with red background spectra when the background and stimulus had the same spectrum. When the background was white, the contrast threshold increased the least with blue and the most with red stimulus spectra. The results show that the spectral sensitivity of the eye is shifted towards shorter wavelengths when photopic background luminance levels are reduced from LB=10 to LB=0.01 cd/m2. The second objective was to find out the differences in the contrast threshold when a white or coloured background spectrum was used. It was found that the differences between the contrast thresholds measured with different stimuli and background spectra were larger when the measurements were taken with a coloured stimulus and a white background. The measured contrast thresholds were applied to existing models for mesopic spectral sensitivity. The goal was to find out if the models describe the mesopic contrast threshold in the same way for different stimulus and background spectra. The models used were Palmer's model [Palmer 1968], the X model [Rea et al 2004], and the MOVE model [Eloholma and Halonen 2005]. It was found that all the models used describe the spectral sensitivity at an eccentricity of 10° at the photopic background luminance levels LB=0.01…10 cd/m2 better than the photopic spectral luminous efficiency function V(λ), when contrast threshold is used as a visual task. It was found that the MOVE model describes the mesopic contrast threshold best at the photopic background luminance levels LB=0.01…3 cd/m2 when a white background and a coloured stimulus were used.
Väitöskirjan ensimmäisenä tavoitteena oli selvittää, kuinka taustan luminanssitaso, taustan spektri ja ärsykkeen epäkeskeisyys vaikuttavat kontrastikynnykseen mesooppisella luminanssialueella. Käytetyt taustan luminassit olivat välillä LB=0.01…20 cd/m2. Nämä luminanssitasot käsittivät tyypilliset tievalaistuksessa esiintyvät luminanssitasot. Taustan ja ärsykkeen spektrit olivat laajakaistaiset sininen, vihreä ja punainen. Mittaukset tehtiin 0 ja 10° epäkeskisyyksillä. Väitöskirjan tulokset vahvistivat sen, että taustan luminanssitason laskiessa arvosta LB=10 cd/m2 arvoon LB=0.01 cd/m2 kontrastikynnys nousee sekä 0 että 10° epäkeskisyyksillä. Tuloksista nähtiin myös, että kontrastikynnys…
Advisors/Committee Members: Helsinki University of Technology, Department of Electrical and Communications Engineering, Lighting Laboratory.
Subjects/Keywords: contrast threshold; mesopic vision; peripheral vision; mesopic spectral sensitivity; models for mesopic vision; kontrastikynnys; mesooppinen näkeminen; ääreisnäkö; mesooppinen spektriherkkyys; mesooppinen malli
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APA (6th Edition):
Ketomäki, J. (2006). Effects of Lighting Parameters on Contrast Threshold in the Mesopic and Photopic Luminance Ranges. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2006/isbn9512283344/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ketomäki, Jaakko. “Effects of Lighting Parameters on Contrast Threshold in the Mesopic and Photopic Luminance Ranges.” 2006. Thesis, Helsinki University of Technology. Accessed January 18, 2021.
http://lib.tkk.fi/Diss/2006/isbn9512283344/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ketomäki, Jaakko. “Effects of Lighting Parameters on Contrast Threshold in the Mesopic and Photopic Luminance Ranges.” 2006. Web. 18 Jan 2021.
Vancouver:
Ketomäki J. Effects of Lighting Parameters on Contrast Threshold in the Mesopic and Photopic Luminance Ranges. [Internet] [Thesis]. Helsinki University of Technology; 2006. [cited 2021 Jan 18].
Available from: http://lib.tkk.fi/Diss/2006/isbn9512283344/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ketomäki J. Effects of Lighting Parameters on Contrast Threshold in the Mesopic and Photopic Luminance Ranges. [Thesis]. Helsinki University of Technology; 2006. Available from: http://lib.tkk.fi/Diss/2006/isbn9512283344/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
24.
Ralls, Daniel M.
Functionalization Dependance of Calix[6]arene Contrast and Sensitivity to Electron Beam Exposure.
Degree: 2013
URL: http://hdl.handle.net/2249.1/62516
Subjects/Keywords: Calixarene; Electron Beam resistance; Sensitivity; Contrast; Physics
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APA (6th Edition):
Ralls, D. M. (2013). Functionalization Dependance of Calix[6]arene Contrast and Sensitivity to Electron Beam Exposure. (Thesis). [No school.] Retrieved from http://hdl.handle.net/2249.1/62516
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No school.
Chicago Manual of Style (16th Edition):
Ralls, Daniel M. “Functionalization Dependance of Calix[6]arene Contrast and Sensitivity to Electron Beam Exposure.” 2013. Thesis, [No school]. Accessed January 18, 2021.
http://hdl.handle.net/2249.1/62516.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No school.
MLA Handbook (7th Edition):
Ralls, Daniel M. “Functionalization Dependance of Calix[6]arene Contrast and Sensitivity to Electron Beam Exposure.” 2013. Web. 18 Jan 2021.
Vancouver:
Ralls DM. Functionalization Dependance of Calix[6]arene Contrast and Sensitivity to Electron Beam Exposure. [Internet] [Thesis]. [No school]; 2013. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/2249.1/62516.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No school.
Council of Science Editors:
Ralls DM. Functionalization Dependance of Calix[6]arene Contrast and Sensitivity to Electron Beam Exposure. [Thesis]. [No school]; 2013. Available from: http://hdl.handle.net/2249.1/62516
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No school.
25.
Costa, Thiago Leiros.
Repercussões visuais da exposição ocupacional a uma mistura de solventes orgânicos: visão cromática e acromática em frentistas brasileiros.
Degree: Mestrado, Psicologia Experimental, 2010, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/47/47132/tde-09022011-113352/
;
► Objetivo: Avaliar repercussões da exposição ocupacional a uma mistura de solventes orgânicos sobre o desempenho visual de um grupo de frentistas. Método: Foram aplicados testes…
(more)
▼ Objetivo: Avaliar repercussões da exposição ocupacional a uma mistura de solventes orgânicos sobre o desempenho visual de um grupo de frentistas. Método: Foram aplicados testes de ordenamento e discriminação de matizes, campo visual e sensibilidade ao contraste espacial de luminância em 25 frentistas (20 homens, M=36,4 anos, DP=8,9) e 25 controles sem histórico de exposição crônica a solventes (10 homens, M=33,8 anos, DP=8,8). As concentrações metabólitos urinários de tolueno (M=0,3 g/g de creatinina; DP=0,16) e xileno (M=0,1 g/g de creatinina; DP=0,02) e o tempo de trabalho (M=9,6 anos; DP=6,2) foram utilizados como indicativos da exposição dos frentistas. Os participantes foram submetidos a exame oftalmológico, e quando necessário, corrigir a acuidade visual para 20/20. Todas as medidas foram realizadas monocularmente com um olho escolhido ao acaso, com exceção do Potencial Visual Evocado Multifocal (PVEmf) e da campimetria. Para avaliar a visão de cores, utilizamos o Lanthony D15-d e Cambridge Colour Test 2.0. Na campimetria estática automatizada foi utilizado o protocolo branco-branco 24-2 do aparelho Humphrey Field Analyzer II-750i. A atividade elétrica visual cortical foi avaliada com o sistema de PVEmf Veris Science 5.2.4, utilizando um estímulo de 60 setores. A sensibilidade ao contraste espacial de luminância foi avaliada no teste Metropsis, para grades senoidais em 7 frequências espaciais de 0,2 a 20,0 cpg. Resultados: Os escores do grupo de frentistas e do grupo controle foram comparados pelo teste Mann-Whitney U. No teste de discriminação de cores (CCT), houve diferença estatística significativa entre controles e frentistas para a área total da elipse (p<0,01), elipticidade (p<0,05) e limiares nos eixos protan, deutan e tritan (p<0,05). No D15d houve diferença significativa entre os 8 dois grupos (p<0,01). Os dados da campimetria apresentaram diferenças significativas entre os dois grupos para as excentricidades de 90, 150 e 210, além dos valores de MD e PSD (p<0,05). Dos três frentistas avaliados com o PVEmf, todos apresentaram uma diminuição significativa (p<0,05) da amplitude do sinal (em relação a dados normativos) em um mínimo de 30 setores do campo visual, resultado que não foi observado no grupo controle. Nos testes de visão de cores, foi encontrada uma correlação (Spearman) positiva e significativa entre o tempo de trabalho e os índices do Lanthony D15d (p=0,52; p<0,05) e os limiares no eixo deutan (p=0,59; p<0,05). Na campimetria, houve correlações negativas significativas com o tempo de trabalho para a área da Fóvea (p=-051; p<0,05), e para os anéis de 30 (p=-0,46; p<0,05), 90 (p=-0,46; p<0,05) e 150 (p=-0,46; p<0,05). Não foi encontrada correlação significativa entre a sensibilidade ao contraste e o tempo de trabalho. Conclusões: Os resultados mostram alterações amplas e difusas no processamento visual em decorrência da exposição crônica a solventes orgânicos
Purpose: To evaluate the outcome of chronic occupational exposure to a mixture of solvents on the visual system of a group of gas…
Advisors/Committee Members: Ventura, Dora Selma Fix.
Subjects/Keywords: Color perception; Contrast sensitivity; Neurotoxicologia; Neurotoxocology; Percepção de cores; Potenciais visuais evocados; Sensibilidade de contraste visual; Solventes; Solvents; Visual evoked potentials
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APA (6th Edition):
Costa, T. L. (2010). Repercussões visuais da exposição ocupacional a uma mistura de solventes orgânicos: visão cromática e acromática em frentistas brasileiros. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/47/47132/tde-09022011-113352/ ;
Chicago Manual of Style (16th Edition):
Costa, Thiago Leiros. “Repercussões visuais da exposição ocupacional a uma mistura de solventes orgânicos: visão cromática e acromática em frentistas brasileiros.” 2010. Masters Thesis, University of São Paulo. Accessed January 18, 2021.
http://www.teses.usp.br/teses/disponiveis/47/47132/tde-09022011-113352/ ;.
MLA Handbook (7th Edition):
Costa, Thiago Leiros. “Repercussões visuais da exposição ocupacional a uma mistura de solventes orgânicos: visão cromática e acromática em frentistas brasileiros.” 2010. Web. 18 Jan 2021.
Vancouver:
Costa TL. Repercussões visuais da exposição ocupacional a uma mistura de solventes orgânicos: visão cromática e acromática em frentistas brasileiros. [Internet] [Masters thesis]. University of São Paulo; 2010. [cited 2021 Jan 18].
Available from: http://www.teses.usp.br/teses/disponiveis/47/47132/tde-09022011-113352/ ;.
Council of Science Editors:
Costa TL. Repercussões visuais da exposição ocupacional a uma mistura de solventes orgânicos: visão cromática e acromática em frentistas brasileiros. [Masters Thesis]. University of São Paulo; 2010. Available from: http://www.teses.usp.br/teses/disponiveis/47/47132/tde-09022011-113352/ ;
26.
Moura, Ana Laura de Araujo.
Percepção de contraste e perdas neurais na esclerose múltipla.
Degree: PhD, Neurociências e Comportamento, 2010, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/47/47135/tde-09022011-112343/
;
► Objetivos: Avaliar a integridade das vias magnocelular (M) e parvocelular (P) atraves da percepcao de contraste e avaliar a sensibilidade no campo visual e respostas…
(more)
▼ Objetivos: Avaliar a integridade das vias magnocelular (M) e parvocelular (P) atraves da percepcao de contraste e avaliar a sensibilidade no campo visual e respostas no ERG multifocal, em pacientes com esclerose multipla. Métodos e Resultados: Foram avaliados 29 pacientes (20F; 9M; idade media = 35,76 }10,91 anos) com diagnostico de esclerose multipla (15 com historico de neurite optica). Todos os pacientes apresentavam acuidade visual entre 0 e 0,1 logMAR. A percepcao de contraste foi avaliada atraves da funcao de sensibilidade ao contraste (programa PSYCHO; Cambridge Research System), com os limiares medidos em 0.2, 0.5, 1.0, 1.9, 5.3, 9.7 e 19.4 ciclos por grau; e do teste do Pedestal (Pokorny & Smith, 1997). O campo visual foi medido com o Campimetro Automatico de Humphrey, algoritmo SITA, estrategia central 24-2. O ERGmf foi registrado, utilizando o sistema VERIS, com 103 hexagonos. A analise foi baseada nos valores de amplitude e latencia de N1 e P1 das respostas de seis regioes predeterminadas de acordo com o mapa sugerido por Garway-Heath et al (2000), para os kernels de primeira e segunda ordem. Os pacientes foram divididos em 2 grupos: NO (antecedente de neurite optica) e SNO (sem antecedente de neurite optica). Resultados: O grupo NO nao diferiu do grupo SNO em nenhum dos testes, exceto nas medidas de amplitude do kernel de segunda ordem no ERGmf (Tukey HSD Test, PostHoc). Todos os pacientes mostraram uma reducao na percepcao de contraste, quando comparados ao grupo controle. Os resultados diferiram significativamente do grupo controle em todas as frequencias espaciais avaliadas na funcao de sensibilidade ao contraste (p < 0.001; ANOVA), e nos dois paradigmas avaliados pelo teste do Pedestal (p <0.05 ANOVA de medidas repetidas). As respostas do kernel de primeira ordem do ERGmf para ambos os grupos, quando comparados com o grupo controle, nao apresentaram diferenca estatistica significativa para as regioes analisadas (p > 0.05; ANOVA de medidas repetidas). As respostas de amplitude dos pacientes, para o kernel de segunda ordem apresentaram-se diferentes do grupo controle, com significancia estatistica para as areas 2, 3, 4, 5 e 6 (p < 0.05; ANOVA de medidas repetidas). Os resultados do campo visual mostraram reducao de sensibilidade nos pacientes em estudo, comparados ao grupo controle, com diferenca estatisticamente significante para todas as regioes (p <0.05; ANOVA de medidas repetidas). Conclusões: Aumento nos limiares de deteccao de contraste foram encontrados nos pacientes com esclerose multipla, em ambos os testes. O padrao de perda nas varias frequencias espaciais e em ambos os paradigmas analisados no teste do Pedestal, sugere um comprometimento nao seletivo das vias visuais, afetando tanto a via parvo como a magnocelular. As alteracoes nas respostas do ERG multifocal detectadas apenas no kernel de segunda ordem poderiam estar relacionadas a danos retrogrados a camada de fibras nervosas da retina causados pela desmielinizacao. Nao foram encontradas correlacoes com as perdas de sensibilidade no…
Advisors/Committee Members: Ventura, Dora Selma Fix.
Subjects/Keywords: Campo visual; Contrast sensitivity; Electrophysiology; Eletrofisiologia; Esclerose múltipla; Multiple sclerosis; Psicofísica; Psychophisics; Sensibilidade de contraste visual; Visual field
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APA ·
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APA (6th Edition):
Moura, A. L. d. A. (2010). Percepção de contraste e perdas neurais na esclerose múltipla. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/47/47135/tde-09022011-112343/ ;
Chicago Manual of Style (16th Edition):
Moura, Ana Laura de Araujo. “Percepção de contraste e perdas neurais na esclerose múltipla.” 2010. Doctoral Dissertation, University of São Paulo. Accessed January 18, 2021.
http://www.teses.usp.br/teses/disponiveis/47/47135/tde-09022011-112343/ ;.
MLA Handbook (7th Edition):
Moura, Ana Laura de Araujo. “Percepção de contraste e perdas neurais na esclerose múltipla.” 2010. Web. 18 Jan 2021.
Vancouver:
Moura ALdA. Percepção de contraste e perdas neurais na esclerose múltipla. [Internet] [Doctoral dissertation]. University of São Paulo; 2010. [cited 2021 Jan 18].
Available from: http://www.teses.usp.br/teses/disponiveis/47/47135/tde-09022011-112343/ ;.
Council of Science Editors:
Moura ALdA. Percepção de contraste e perdas neurais na esclerose múltipla. [Doctoral Dissertation]. University of São Paulo; 2010. Available from: http://www.teses.usp.br/teses/disponiveis/47/47135/tde-09022011-112343/ ;
Texas Medical Center
27.
Flynn, Jonathan R.
On the Origin of Sensory Errors.
Degree: PhD, 2017, Texas Medical Center
URL: https://digitalcommons.library.tmc.edu/utgsbs_dissertations/760
► Estimation of perceptual variables is imprecise and prone to errors. Although the properties of these perceptual errors are well characterized, the physiological basis for…
(more)
▼ Estimation of perceptual variables is imprecise and prone to errors. Although the properties of these perceptual errors are well characterized, the physiological basis for these errors is unknown. One previously proposed explanation for these errors is the trial-by-trial variability of the responses of sensory neurons that encode the percept. Initially, it would seem that a complicated electrophysiological experiment would need to be performed to test this hypothesis. However, using a strong theoretical framework, I demonstrate that it is possible to determine statistical characteristics of the physiological mechanism responsible for perceptual errors solely from a behavioral experiment. The basis for this theoretical framework is that different stochastic distributions (e.g., Poisson, Gaussian, etc.) will behave differently under temporal constraints. The results of this model connect easily with existing psychophysical techniques; additionally, I extend the theory here and show that it can generate realistic tuning curves that can predict perceptual acuity as a function of stimulus magnitude and duration. Following the analytical work, I performed the necessary experiments to test the model. I demonstrate that the physiological basis of perceptual error has a constant level of noise (i.e., independent of stimulus intensity and duration). By comparing these results to previous physiological measurements, I show that perceptual errors cannot be due to the variability during the encoding stage. Further, I show a very close fit between the theoretically generated tuning curve and the behavioral results, which gives more insight into the error generation mechanism. Finally, I find that the time window over which perceptual evidence is integrated lasts no more that ~230ms. I discuss these results and others, and speculate on sources of error that may be consistent with my behavioral measurements.
Advisors/Committee Members: Harel Shouval, Valentin Dragoi, Giridhar Kalamangalam.
Subjects/Keywords: contrast sensitivity; encoding/decoding; neuron; noise; detection/discrimination; Behavioral Neurobiology; Cognitive Neuroscience; Computational Neuroscience; Medicine and Health Sciences; Systems Neuroscience
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MLA ·
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APA (6th Edition):
Flynn, J. R. (2017). On the Origin of Sensory Errors. (Doctoral Dissertation). Texas Medical Center. Retrieved from https://digitalcommons.library.tmc.edu/utgsbs_dissertations/760
Chicago Manual of Style (16th Edition):
Flynn, Jonathan R. “On the Origin of Sensory Errors.” 2017. Doctoral Dissertation, Texas Medical Center. Accessed January 18, 2021.
https://digitalcommons.library.tmc.edu/utgsbs_dissertations/760.
MLA Handbook (7th Edition):
Flynn, Jonathan R. “On the Origin of Sensory Errors.” 2017. Web. 18 Jan 2021.
Vancouver:
Flynn JR. On the Origin of Sensory Errors. [Internet] [Doctoral dissertation]. Texas Medical Center; 2017. [cited 2021 Jan 18].
Available from: https://digitalcommons.library.tmc.edu/utgsbs_dissertations/760.
Council of Science Editors:
Flynn JR. On the Origin of Sensory Errors. [Doctoral Dissertation]. Texas Medical Center; 2017. Available from: https://digitalcommons.library.tmc.edu/utgsbs_dissertations/760
University of Newcastle
28.
Mikulskaya, Elena.
Visual processing, visual attention and their neural correlates in early-onset cannabis users.
Degree: PhD, 2016, University of Newcastle
URL: http://hdl.handle.net/1959.13/1312742
► Research Doctorate - Doctor of Philosophy (PhD)
Cannabis use worldwide has been increasing steadily over the past decade. The current trend towards legalization of cannabis…
(more)
▼ Research Doctorate - Doctor of Philosophy (PhD)
Cannabis use worldwide has been increasing steadily over the past decade. The current trend towards legalization of cannabis for medical purposes and/or recreational use increases the potential to expose more and younger people to cannabis. Early age of onset has been linked to visual and attentional deficits in adulthood suggested to arise from blunted dopaminergic functioning. Dopamine is a neurotransmitter, critically important for efficient visual and attentional functioning in addition to general cognitive and motor behaviour. The overall aim of this thesis was to investigate in depth low level visual processing (Phase 1) and visual attention and underlying neural processing (Phase 2) in early-onset cannabis users. Static and dynamic contrast thresholds were examined in Experiments 1 and 2 and motion discrimination thresholds were examined in Experiment 3 under normal and low luminance conditions. An index of brain dopamine production was also collected and compared in Experiment 4. Static but not dynamic contrast detection thresholds were significantly higher in the cannabis group (21 participants: 18 of whom commenced cannabis use before the age of 17) compared to the control group (20 participants) under mesopic levels of luminance. Both static and dynamic contrast thresholds were positively correlated with frequency of use in the cannabis group. Discrimination of direction of translational and radial motion was examined in Experiment 3 under normal and mesopic luminance and at two levels of stimuli contrast: 12 and 24%. Independently of luminance level and motion type, coherence thresholds were significantly higher in the cannabis group at 24% stimuli contrast compared to the control group and in particular the thresholds were higher for radial compared to translational motion, although the differences failed to reach statistical significance. Again, the thresholds in the cannabis group were higher with more frequent cannabis use. We also found significantly lower spontaneous Eye Blink Rate (EBR) in the cannabis group compared to the control group in Experiment 4. We argued that lower dopamine may underlie the higher thresholds shown by the cannabis group across all visual tasks in Phase 1. In Phase 2 of this thesis behavioural data and EEG recordings were collected from 53 participants in four experiments. ERPs and gamma band activity were extracted from EEG recordings and compared between the control group (29 participants) and the cannabis group (24 participants: all commenced cannabis use before age 17). In Experiment 5 we investigated the neural correlates (ERPs and gamma band activity) of radial motion processing to further investigate the results of Experiment 3. As expected reduced ERP amplitudes to motion stimuli were shown by the cannabis group compared to the control group. Motion stimuli were also employed in the oddball task in Experiment 6 in which we aimed to investigate the neural correlates of selective attention. The cannabis group showed…
Advisors/Committee Members: University of Newcastle. Faculty of Science & Information Technology, School of Psychology.
Subjects/Keywords: contrast sensitivity; motion processing; oddball; word recognition; masked semantic priming; early-onset cannabis use; ERPs; gamma oscillations; eye blink rate
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APA ·
Chicago ·
MLA ·
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CSE |
Export
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APA (6th Edition):
Mikulskaya, E. (2016). Visual processing, visual attention and their neural correlates in early-onset cannabis users. (Doctoral Dissertation). University of Newcastle. Retrieved from http://hdl.handle.net/1959.13/1312742
Chicago Manual of Style (16th Edition):
Mikulskaya, Elena. “Visual processing, visual attention and their neural correlates in early-onset cannabis users.” 2016. Doctoral Dissertation, University of Newcastle. Accessed January 18, 2021.
http://hdl.handle.net/1959.13/1312742.
MLA Handbook (7th Edition):
Mikulskaya, Elena. “Visual processing, visual attention and their neural correlates in early-onset cannabis users.” 2016. Web. 18 Jan 2021.
Vancouver:
Mikulskaya E. Visual processing, visual attention and their neural correlates in early-onset cannabis users. [Internet] [Doctoral dissertation]. University of Newcastle; 2016. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/1959.13/1312742.
Council of Science Editors:
Mikulskaya E. Visual processing, visual attention and their neural correlates in early-onset cannabis users. [Doctoral Dissertation]. University of Newcastle; 2016. Available from: http://hdl.handle.net/1959.13/1312742
University of Johannesburg
29.
Ramkissoon, Prithipaul.
The effect of tinted lenses on colour discrimination and contrast sensitivity.
Degree: 2008, University of Johannesburg
URL: http://hdl.handle.net/10210/1347
M. Phil.
Please refer to full text to view abstract
Prof. J.T. Ferreira
Subjects/Keywords: Ophthalmic lenses; Color vision; Contrast sensitivity (Vision)
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APA ·
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APA (6th Edition):
Ramkissoon, P. (2008). The effect of tinted lenses on colour discrimination and contrast sensitivity. (Thesis). University of Johannesburg. Retrieved from http://hdl.handle.net/10210/1347
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ramkissoon, Prithipaul. “The effect of tinted lenses on colour discrimination and contrast sensitivity.” 2008. Thesis, University of Johannesburg. Accessed January 18, 2021.
http://hdl.handle.net/10210/1347.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ramkissoon, Prithipaul. “The effect of tinted lenses on colour discrimination and contrast sensitivity.” 2008. Web. 18 Jan 2021.
Vancouver:
Ramkissoon P. The effect of tinted lenses on colour discrimination and contrast sensitivity. [Internet] [Thesis]. University of Johannesburg; 2008. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/10210/1347.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ramkissoon P. The effect of tinted lenses on colour discrimination and contrast sensitivity. [Thesis]. University of Johannesburg; 2008. Available from: http://hdl.handle.net/10210/1347
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Purdue University
30.
Claus, Benjamin J.
CHARACTERISTICS OF FIBROUS TISSUE AT HIGH RATES OF TENSILE LOADING.
Degree: MS, Aeronautics and Astronautics, 2014, Purdue University
URL: http://docs.lib.purdue.edu/open_access_theses/163
► The mechanical behavior of fibrous tissue is generally characterized at very low strain rates. However, many injuries occur at high rates of loading, such…
(more)
▼ The mechanical behavior of fibrous tissue is generally characterized at very low strain rates. However, many injuries occur at high rates of loading, such as those encountered in sporting events or vehicle accidents. An understanding of injury behavior requires the injury process to be recorded at high strain rates. Even at low rates of loading, the injury/failure within tissues occurs quickly. Furthermore, using conventional imaging systems, the surface of a specimen may be well documented throughout an experiment. However, damage formation does not necessarily begin at the surface of the specimen or even on the surface exposed to a camera. With the integration of a tension Kolsky bar and X-Ray Phase
Contrast Imaging (PCI), damage formation within a specimen can be observed without knowledge of when the damage event occurs and without regard for the opaqueness of the specimen. By using these two systems at higher strain rates, the damage event can be correlated with load data, acceleration, and strain rate.
Advisors/Committee Members: Weinong Chen, James F. Doyle, Eric A. Nauman.
Subjects/Keywords: Biological sciences; Health and environmental sciences; Damage mechanisms; Kolsky bar; Medial collateral ligament; Phase contrast imaging; Rate sensitivity; Biomechanics and Biotransport
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APA (6th Edition):
Claus, B. J. (2014). CHARACTERISTICS OF FIBROUS TISSUE AT HIGH RATES OF TENSILE LOADING. (Thesis). Purdue University. Retrieved from http://docs.lib.purdue.edu/open_access_theses/163
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Claus, Benjamin J. “CHARACTERISTICS OF FIBROUS TISSUE AT HIGH RATES OF TENSILE LOADING.” 2014. Thesis, Purdue University. Accessed January 18, 2021.
http://docs.lib.purdue.edu/open_access_theses/163.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Claus, Benjamin J. “CHARACTERISTICS OF FIBROUS TISSUE AT HIGH RATES OF TENSILE LOADING.” 2014. Web. 18 Jan 2021.
Vancouver:
Claus BJ. CHARACTERISTICS OF FIBROUS TISSUE AT HIGH RATES OF TENSILE LOADING. [Internet] [Thesis]. Purdue University; 2014. [cited 2021 Jan 18].
Available from: http://docs.lib.purdue.edu/open_access_theses/163.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Claus BJ. CHARACTERISTICS OF FIBROUS TISSUE AT HIGH RATES OF TENSILE LOADING. [Thesis]. Purdue University; 2014. Available from: http://docs.lib.purdue.edu/open_access_theses/163
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
◁ [1] [2] [3] [4] ▶
. 
Open Access Theses and Dissertations