J Timothy Petersik

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Gaps in past literature have raised questions regarding the kinds of stimuli that can lead to three-dimensional (3-D) rotation aftereffects. Further, the characteristics of the buildup and decay of such aftereffects are not clear. In the present experiments, rotation aftereffects were generated by projections of cube-like stimuli whose dynamic perspective(More)
Researchers often assume a critical band of spatial frequencies is required for face recognition. Also, many studies have not measured the contrast required for recognition. On Day 1, observers viewed high-pass-filtered (HP), low-pass-filtered (LP), or unfiltered (UF) faces. On Day 2, they viewed a variety of faces, some of which were LP filtered, HP(More)
The Ternus effect involves a multi-element stimulus that can lead to either of two different percepts of apparent movement depending upon a variety of stimulus conditions. Since Ternus's 1926 discussion of this phenomenon, many researchers have attempted to explain it. We examine the history of explanations of the Ternus effect and show that they have(More)
We cite two different perceptual-correspondence principles whose emphasis can help to disambiguate the otherwise ambiguous Ternus display in apparent movement (a display that can alternately be seen in one of two possible configurations). One of these principles is spatial correspondence, which emphasizes the maintenance of similar stimulus elements in(More)
Two bistable apparent-movement displays (i.e. ones that generate two qualitatively different kinds of movement percepts under different conditions) were compared. They were designed to be as similar as possible spatially, and were studied with identical stimulus manipulations to see whether changes in balance between their bistable percepts would be(More)
Using a bistable apparent-motion display, Odic and Pratt (2008, Perception 37 1790-1804) have recently presented data that they interpret as being inconsistent with what they call "the two-process theory". Instead, they argue, their data can be explained by the differential-activation theory along with a process they identify as "temporal summation of(More)
The Ternus display is an ambiguous, multi-element, apparent-movement animation which can be perceived in two alternative organizations. One of these involves the simultaneous movement of several elements and is called group movement. The other involves the movement of one element only and is called element movement. The present study examined the influence(More)
Five experiments probed the conditions under which observers fail to report instantaneous reversals in the direction of motion of pixels that define the rotation of a transparent sphere or plane. Our results showed that the extent to which rotation reversals were not reported depended upon whether observers used strict or lax criteria to make their(More)
Four experiments and controls were run in order to determine the ability of the visual system to detect slight changes in three-dimensional (3D) rotating stimuli in comparison to two-dimensional (2D) controls. A small number of observers (between 5 and 8) viewed computerized displays of pixel-defined transparent rotating spheres or circular patches of(More)