Sex differences in the perception of autokinetic movement of an afterimage

The effects of stimulus color and gender upon the perception of an afterimage were examined. The Ss were 32 male and 32 female college undergraduate volunteers. Eight Ss of each gender viewed a pinpoint flash of light through one of four filters: blue-green (Wratten 44A), red (Wratten 92), yellow (Wratten 9), or a neutral (Wratten 96) filter. Each S was given three trials, and on each trial, the duration of the afterimage was recorded, along with changes of direction, and changes in perceived color. Males reported significantly (p less than .05) more autokinetic movement of the afterimage. The color of the stimulus affected afterimage duration differentially for the two genders (p less than .05), and there was also a significant interaction (p less than .02) of gender with filter color for the total number of color changes reported. Thus, it is likely that both outflow monitoring and error signal variables in the autokinetic effect may be affected by gender, and the two sexes may also have different retinal and/or central processing of visual information.