Matching Items (2)
Description
The present study explores the role of motion in the perception of form from dynamic occlusion, employing color to help isolate the contributions of both visual pathways. Although the cells that respond to color cues in the environment usually feed into the ventral stream, humans can perceive motion based on chromatic cues. The current study was designed to use grey, green, and red stimuli to successively limit the amount of information available to the dorsal stream pathway, while providing roughly equal information to the ventral system. Twenty-one participants identified shapes that were presented in grey, green, and red and were defined by dynamic occlusion. The shapes were then presented again in a static condition where the maximum occlusions were presented as before, but without motion. Results showed an interaction between the motion and static conditions in that when the speed of presentation increased, performance in the motion conditions became significantly less accurate than in the static conditions. The grey and green motion conditions crossed static performance at the same point, whereas the red motion condition crossed at a much slower speed. These data are consistent with a model of neural processing in which the main visual systems share information. Moreover, they support the notion that presenting stimuli in specific colors may help isolate perceptual pathways for scientific investigation. Given the potential for chromatic cues to target specific visual systems in the performance of dynamic object recognition, exploring these perceptual parameters may help our understanding of human visual processing.
ContributorsHolloway, Steven R. (Author) / McBeath, Michael K. (Thesis advisor) / Homa, Donald (Committee member) / Macknik, Stephen L. (Committee member) / Arizona State University (Publisher)
Created2011
Description
The interplay between Post Traumatic Stress Disorder (PTSD) and self-efficacy lies in the efficacy-activated processes that comprise an individual’s cognitive and belief systems. Previous research shows that low self-efficacy contributes to development and maintenance of mental disorders like PTSD, while high self-efficacy influences ability to visualize, implement, and maintain success scenarios (resilience) related to effective mental coping. Negative cognition makes it difficult to pursue a coping success scenario in the presence of overriding self-doubt and often arises because a traumatic event has made it difficult to retrieve positive self-identities or has reactivated negative self-identities. Consistent with this model, we predict that a negative association exists between self-efficacy and PTSD onset susceptibility. We employed a pre-test/post-test design using a susceptibility/resilience questionnaire to assess predisposition to PTSD. Vignettes, designed to either raise or lower self-efficacy, were used to separate participants into groups and revealed a significant interaction between low and high self-efficacy across the pre- and post-tests, supporting the assertion that high self-efficacy guards against PTSD onset susceptibility while low self-efficacy may make someone more susceptible to developing PTSD-related symptoms.
ContributorsNightingale, Jeffrey W (Co-author) / Holloway, Steven R. (Thesis director) / Náñez, José E. (Committee member) / School of Social and Behavioral Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05