Organizational and visual memory deficits in schizophrenia and bipolar psychoses using the Rey-Osterrieth complex figure: effects of duration of illness.

Abstract

Verbal declarative memory deficits in schizophrenia are well documented whereas visual declarative memory is less studied. Moreover, there are limited data on whether organizational and visual memory deficits are specific to schizophrenic psychoses. We compared visual memory and organizational function in patients with chronic schizophrenia (n=79) and chronic bipolar psychotic disorder (n=14), and in healthy controls (n=84) using the Rey-Osterrieth Complex Figure (ROCF), testing whether organizational impairments (i.e., executive dysfunctions) account for the visual memory deficit. Groups were comparable on age, handedness and expected intellectual ability (based on single word reading). Using analyses of covariance with sex, parental SES and ethnicity as co-variates, patients with schizophrenia were significantly more impaired than controls on copy accuracy, on recall accuracy, and on percent accuracy of recall. Patients with schizophrenia used a more detail-oriented style on copy and recall and had significantly worse recognition memory. After co-varying IQ, copy organization was also significantly different between the groups. Results for accuracy of copy and recall were not significantly attenuated when controlling for copy organization. Duration of illness was associated with visual memory. Bipolar patients performed at an intermediate level between controls and patients with schizophrenia. The data suggest that in schizophrenia, patients have a visual memory disorder characterized by both organizational processing impairments and retention difficulties, and that there is a decline in visual memory functions with duration of illness. Further research is required to determine whether similar mechanisms underlie the neurocognitive deficits in these psychotic disorders.