Introduction: The aim of this research was investigation of attention and perception disorders in schizophrenic people and comparison with normal ones. Method: Method of the research is experimental. 30 schizophrenic subjects were randomly selected from three psychiatric hospitals of Tehran City and compared with 30 normal subjects. Chronoscope apparatus was used to assess reaction time to light and sound stimuli. The apparatus assesses the light and sound stimuli in 0/001 seconds. Independent T-test was used to analyze and compare means of experiment group (schizophrenic subjects) with control group (normal subjects). Results: There were statistically meaningful differences between two groups' means. Normal subjects were much more rapid in reaction and responding to light and sound stimuli than schizophrenic subjects. Conclusion: Schizophrenic subjects can't response rapid to light and sound stimuli, because of their affective and emotional disorders and depressed temperament which caused disorder in abilities and functions.