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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 …