Based on clinical observations individuals with schizophrenia have deficits in a large number of functional domains, including social skills, social cognition, difficulties in perceiving, understanding, anticipating and reacting to social cues and deficient in social networks that are crucial for normal social interaction. (Yager and Ehmann, 2006). Disturbances and disorders in the domains are thought to explain impairments in social functioning that potentially have an direct link to social behavior, social function and interaction with others. in this field and for better and more understanding about schizophrenia, the study aims to investigate reaction time to stimuli in the field of light and sound attention and perception in schizophrenic patients and comparison with normal people.

Method of the research is experimental. 30 schizophrenic subjects were randomly selected from three psychiatric hospitals 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).

Analysis of means showed differences between groups. Normal subjects were much more rapid in reaction and responding to light and sound than schizophrenic subjects.

Findings showed schizophrenic subjects because of their affective and emotional disorders and depressed temperament that caused to disorder in abilities and functions, cannot response rapid to light and sound than normal people.