Effects of extraneous stimulation on visual afterimage serials produced by young schizophrenics

Smith, G. J. W. & Ruuth, E. Effects of extraneous stimulation on visual afterimage serials produced by young schizophrenics. Scand. J. Psychol., 1973, 14, 34–38.- Two groups of young schizophrenics, 20 in each, produced afterimages (Als) of a schematic face in 20 consecutive trials. In one group an acoustic signal was administered at the 8th, 12th and 16th trials. The signal effect in a previous experiment implied that the ongoing adaptive trend was disrupted by a return to the trend characterizing the before-signal portion of the sequence. This result was cross-validated, with particular emphasis put on the regressive characteristics shown by schizophrenics. However, the present schizophrenic subjects seemed to be more resistant to the contraction and eventual mechanization of their adaptive processes being the usual consequence of iteration.