Reproduction of tactually perceived forms.

Forms were actively touched with the preferred palm or fingers, or were passively drawn or pressed on the palms of 80 subjects with vision excluded. The subjects were either limited to 2 sec. of exposure time or were allowed to experience the forms as long as they wished. They were then required to draw the forms they had touched. Unlimited stimulus exposure proved of greater systemic benefit to active than passive touch. The fingers produced better form detection than the other conditions, and the active-plan condition was also superior to passive touch when sufficient exposure time was permitted. Subjects in all passive touch conditions frequently reported gaps in the forms where none existed, while active touch led to more adequate perception of closure. It was suggested that passivity impedes the formation of unitary percepts.