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This report extends findings (Duffy & Mitchell, 2013) of a dramatic recovery of vision in the deprived eye of amblyopic kittens following a short ‘dark-pulse’ (a 10 day period of darkness) to situations of clinical relevance. To this end, the initial deprivation began at post-natal day 7 rather than post-natal day 30. As before, the dark-pulse was imposed either immediately after the initial monocular deprivation, or was delayed several weeks after stable amblyopia was establsihed. In some animals, this dark-pulse was shortened, or disrupted by short periods of daily binocular visual experience. The effects on the visual acuity and alignment acuity of the two eyes were documented as well as the effects on binocular depth perception. The benefits of a short dark-pulse were identical to those of the prior study. A dark-pulse of 5 days was ineffective as was a dark-pulse interrupted daily by light for 30-minutes.

This study aimed to determine whether the rate of perceptual learning in a vernier discrimination task could be influenced by affective images. Forty-eight (30 Female, 18 Male) subjects were instructed to indicate the direction of an offset over 620 trials. Subjects were primed with either negative, positive or neutral photographs before making the discrimination on all test trials. Feedback regarding offset performance was provided on each trial. Despite initial pilot data indicating that subjects primed with negative, arousing images improved performance over those primed with either neutral or positive images, there was ultimately no reliable advantage for any of the affective prime conditions.

The focus of this thesis is on the transition from 2D character design to 3D model design, and how this transition affects the appeal, fluidity, and clarity of the 2D design. The source material for this project was an original screenplay entitled The Birds Work for Bea. Three characters from the material were selected for a process including ideation, research, 2D character and style exploration, 3D sculpting, and 3D printing and finishing. This project serves as a study in all aspects of the character concept development pipeline.

This creative thesis explores the process of visual development and how one can apply it to their own body of work. Visual Development encompasses the entire concept design process, from the idea to the final design. Vis Dev artists document their journey to depict how an idea becomes a fully refined and polished concept. They illustrate a wide variety of elements, such as characters, costuming, props, and environments. The development of all of these factors then allows the artist to cultivate an imaginative and creative world that could be used for multiple forms of entertainment, such as animated films, video games, and comics. This project follows the visual development process to create a lineup of 4 space-themed circus characters, their pose and expression sheets, and 2 key illustrations.

Adults perceive basic emotional facial expressions as discrete categories using categorical perception. Within categorical perception, discrimination of facial emotional expressions is better for between category faces than within category faces. In this thesis, I examined the developmental trajectory of categorical perception in early childhood. I also examined the relationship between sensitivity to physical differences in facial emotional expressions and the use of emotion labels in toddlers. In Chapter 2, I found that infants before 12-months failed to discriminate between category faces along a happy-sad continuum. In contrast, evidence suggest that 9- and 12-month old infants categorically perceived faces along a happy-angry continuum. These findings suggest that categorical perception may not develop concurrently for all emotions. In Chapter 3, I found that toddlers by 26-months of age categorically perceived faces along a happy-sad continuum. These results highlight the long developmental trajectory of categorical perception of facial emotional expressions across early childhood. In Chapter 4, I found a relationship between perceptual sensitivity to physical differences between happy and sad faces, and the emotion vocabulary size in 26-month-olds. This relationship suggests that learning about emotions may utilize information from multiple domains, and that learning in one domain may influence the development of another. The perception of facial emotional expressions is an essential component of early social emotional development. Categorical perception is a mechanism that aids in organizing complex social information from faces into actionable categories. The research in this thesis advances our understanding of early social perceptual development and the process that allow us to successfully navigate in the social world. / Dissertation / Doctor of Philosophy (PhD) / Humans are experts at reading faces. Specifically, they are capable of interpreting complex social information from faces, including emotions, and using this information to navigate social situations. In order to organize facial emotional information, humans use a mechanism called categorical perception to quickly and efficiently sort facial emotional information into discrete categories. Inferences can be made about members within a category, which aids in the prediction and production appropriate behaviours. However, there has been limited research into the development of categorical perception in early childhood. The key goal of this thesis was to develop infant and toddler appropriate methodologies that capture the development categorical perception. In this thesis, I found that categorical perception does not develop uniformly across all ages and between different emotions. Results suggest that perceptual sensitivity to differences in facial emotional expression may be influenced by the use of emotion labels, or vice versa.

A Catarata Congênita (CC) é definida como a opacidade do cristalino, que está presente no nascimento ou surge logo após. Pode ser classificada de acordo com sua morfologia, posição, densidade e seu prognóstico varia conforme a morfologia e precocidade do diagnóstico e tratamento. Devido à privação visual na Catarata Congênita, ocorre o impedimento da evolução orgânica e funcional de maneira adequada do sistema visual, levando a alterações que resultam na baixa visão, além afetar componentes da retina e áreas do cérebro relacionados com o processamento de cores. O objetivo deste trabalho foi verificar o impacto da no desenvolvimento da visão de cores e acuidade visual entre crianças tratadas da catarata congênita. Foram avaliados 2 grupos: 16 crianças do grupo controle e 16 crianças do grupo CC. Foi utilizado os Cartões de Acuidade de Teller para avaliar a acuidade visual e uma versão adaptada para avaliação de crianças do Cambridge Colour Test (CCT) para a avaliação dos três eixos de visão de cores (protan, deutan e tritan). Houve redução de Acuidade visual de todas as crianças do grupo CC além de redução nos eixos deutan e protan quando comparados com o grupo controle, principalmente o eixo protan. Foi encontrada correlação entre o eixo protan e acuidade visual, inferindo assim que há uma alteração na retina central e na via parvocelular em crianças com CC / Congenital Cataracts (CC) is defined as lens opacity, present at birth or appearing soon after. This condition can be classified according to morphology, position and density, and the prognosis varies according to morphology and early diagnosis and treatment. Due to visual deprivation in Congenital Cataracts, the organic and functional evolution of the visual system is impaired, leading to changes that result in poor vision, while also affecting retina components and brain areas related to color processing. The aim of this study was to verify the impact on the development of color vision and visual acuity among children who underwent congenital cataracts treatment. Two groups were evaluated: 16 children in the control group and 16 in the CC group. Teller\'s Acuity Cards were used to evaluate visual acuity, and an adapted version of the Cambridge Color Test (CCT) was applied to evaluate the three color vision axes (protan, deutan and tritan). Decreased visual acuity was observed for all children in the CC group, as well as in the deutan and protan axes when compared to the control group, primarily the protan axis. A correlation was detected between the protan axis and visual acuity, thus inferring that changes in the central retina and the parvocellular pathway in children with CC do indeed occur

Medimos a acuidade visual em crianças com paralisia cerebral do tipo espástica, classificadas em tetraplégicas, diplégicas e hemiplégicas, de acordo com o seu prejuízo motor, pelo método dos potenciais visuais evocados de varredura. Encontramos uma redução na acuidade visual em todos as crianças com tetraplegia e diplegia e em 94% das crianças com hemiplegia. Ambliopia foi identificada em 16% das crianças. Uma alta correlacão entre o prejuízo motor e a redução da acuidade visual foi encontrada para todas as classes. Concluímos que a acuidade visual está reduzida na paralisia cerebral espástica e que esta é de origem cortical, uma vez que o exame oftalmológico de todas as crianças era normal. / We measured the visual acuity in children with spastic cerebral palsy classified as tetraplegic, diplegic and hemiplegic according to their motor impairment by the sweep visual evoked potential method. We found a reduction in the visual acuity of all tetraplegic and diplegic and in 94% of the hemiplegic children. Ambliopia was found in 16% of children. A high correlation was found between the motor impairment and the reduction in the visual acuity. We conclude that the visual acuity was reducted in the spastic cerebral palsy and the origins are presumed to be cortical since the ophthalmological exam in all children was normal.

To coordinate visual perception and motor control in daily life where we are constantly surrounded by motion, we are dependent on normal visuomotor capacity. One essential prerequisite for normal visuomotor capacity is smooth pursuit eye movements (SP). Infants born very preterm (VPT = born <32 gestational weeks) are at high risk of developing disabilities in higher brain functions i.e. perception, cognition, concentration and coordination. In this thesis visuomotor capacity was investigated in a cohort of VPT infants (n = 113) and compared to control groups of full term (FT) infants. Levels of SP were measured at 2 and 4 months’ corrected age (CA). At 8 months’ CA reaching capacity toward a moving object was evaluated as this represents an executive activity guided by vision that develops at an early age. Lower levels of SP were found in the VPT infants compared to FT controls. The VPT boys showed higher levels of SP compared to the VPT girls. In VPT infants without major neonatal morbidities lower levels of SP was found compared to the FT controls. No difference in total capacity of gaze tracking was found, although the VPT infants lagged the object more at 4 months’ CA and used more saccades at 2 months’ CA. With age the VPT infants’ SP levels increased, but with a wider dispersion compared to the FT controls, and the levels of SP at 4 months’ CA corresponded to the levels of the FT infants at 2 months.  A number of perinatal risk factors were found to be negatively associated to lower levels of SP, and this effect was more pronounced in VPT infants with multiple risk factors,.  When evaluating the capacity to reach a moving object at 8 months’ CA, the VPT infants showed significantly more bimanual reach and more curved reaching paths to catch the object as compared to the FT control group. In conclusion, a delayed visuomotor capacity was found in VPT infants compared to FT control infants at 2, 4 and 8 months’ CA. Some VPT infants with perinatal risk factors did not develop in levels of SP between 2 and 4 months’ CA.