Differential effect of prior event information on reaction time with respect to paranoid vs nonparanoid symptomatology

Abstract

The effect on reaction time, of prior information concerning the imperative stimulus, was investigated with respect to the dimension of paranoid vs nonparanoid symptomatology of schizophrenia. In the first experiment, the auditory warning signal was followed by the imperative stimulus, which was a straight line, a triangle or a rectangle. Prior information was provided by means of correlation between pitch of the warning signal and shape of the imperative stimulus. The task was to depress the telegraph key promptly at the onset of the imperative stimulus. Twenty chronic undifferentiated schizophrenics, 20 paranoid schizophrenics and 20 alcoholics participated in the experiment. Reaction time of the chronic undifferentiated schizophrenics increased, and reaction time of the paranoid schizophrenics decreased, when the prior event information was provided. In the second experiment, the imperative stimulus consisted of not only different shapes but also different colors. Reaction times of 20 chronic undifferentiated and 20 paranoid schizophrenics were again affected in opposite directions by prior information. In the third experiment, the imperative stimulus was either 1, 3 or 5 dark dots. Twenty each of the chronic undifferentiated and paranoid schizophrenics participated in the experiment. The opposite effects of prior information on reaction time with respect to the dimension of paranoid vs nonparanoid symptomatology, were again demonstrated. It was concluded that paranoid vs nonparanoid symptomatology is based on two elementary processes which are dichotomous and characteristically different from each other.