Selective attention impairment in Schizophrenia: can it explain source monitoring failure?
Reality monitoring and selective attention have been repeatedly shown to be impaired in schizophrenia. Positive symptomatology has been found to be associated with deficits in both reality monitoring and selective attention. Therefore, a direct link between reality monitoring and selective attention was hypothesized. Thirty-two schizophrenic patients and 32 normal controls were administered the Stroop test as a measure of selective attention along with a test of three indices of reality monitoring, involving discrimination of: events vs. non-events, self- vs. externally-generated events, and oral vs. pictorial sources. A global memory test was administered for comparison. Results showed that schizophrenic patients were impaired in both reality monitoring and selective attention, and that these two were significantly correlated with each other in the schizophrenic sample. On the contrary, selective attention was not significantly correlated with memory efficiency in either group. Further, multiple regression analyses in schizophrenic patients showed that only selective attention contributed significantly to the variance in reality monitoring measures. Therefore, the results argue in favor of a specific role of a selective attention deficit in reality monitoring failure in schizophrenia.