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Full-Text Articles in Psychology
Dot Polarity In Dynamic Glass Patterns, Dawn Vreven, Timothy Petersik, Jim Dannemiller, Jamie Schrauth
Dot Polarity In Dynamic Glass Patterns, Dawn Vreven, Timothy Petersik, Jim Dannemiller, Jamie Schrauth
Dawn L Vreven
Each frame of a Glass pattern consists of a random placement of dots and a spatially shifted copy of this pattern. Thus, each dot has a partner, forming dot-pair dipoles. When shown in succession, motion is perceived along the axis of the spatial shift. The perception of motion in dynamic Glass patterns is believed to be a two-stage process: first, local orientation detectors respond to the orientation signal in the dot-pair dipole; and second, global detectors integrate local orientation signals. We examined the ability to detect rotation in dynamic Glass patterns whose dipoles contained a) the same polarity, b) opposite …
Integration Of Speed Signals In The Direction Of Motion, Dawn Vreven, Preeti Verghese
Integration Of Speed Signals In The Direction Of Motion, Dawn Vreven, Preeti Verghese
Dawn L Vreven
Speed discrimination tasks were used to examine the spatial and temporal characteristics of the integration mechanism involved when signals are extended in the direction of motion. We varied the aspect ratio of a signal patch whose speed differed from the background, while holding the area of the signal patch constant, so that the signal patch could be either extended in the direction of motion or extended orthogonal to the direction of motion. Speed discrimination thresholds decreased dramatically as the signal patch was extended in the direction of motion. The spatial and temporal integration regions were larger than would be expected …
Detecting Structure In Glass Patterns: An Interocular Transfer Study, Dawn Vreven, Jarrod Berge
Detecting Structure In Glass Patterns: An Interocular Transfer Study, Dawn Vreven, Jarrod Berge
Dawn L Vreven
Glass patterns are visual stimuli used here to study how local orientation signals are spatially integrated into global pattern perception. We measured a form aftereffect from adaptation to both static and dynamic Glass patterns and calculated the amount of interocular transfer to determine the binocularity of the detectors responsible for the perception of global structure. Both static and dynamic adaptation produced significant form aftereffects and showed a very high degree of interocular transfer, suggesting that Glass-pattern perception involves cortical processing beyond primary visual cortex. Surprisingly, dynamic adaptation produced significantly greater interocular transfer than static adaptation. Our results suggest a functional …