Memory impairment has been acknowledged as a core cognitive deficit in schizophrenia, however distinct functional subtypes of memory are differently impaired in these patients.

To assess working memory in schizophrenia patients.

Forty schizophrenia inpatients, mean age 29.1 years from the 3rd Psychiatric Clinic Cluj-Napoca, Romania, were included. Exclusion criteria were mental retardation, history of drug or alcohol use, neurological or systemic conditions, recent electroconvulsive therapy. The control group consisted of 30 healthy subjects (mean age = 29.6). The Word List Memory Test (WLM), the Face Memory Test and the Spatial Working Memory Test on a Cogtest Console were used in the assessment of the 2 groups.

Schizophrenia patients displayed specific impairments of working memory, such as lower learning (42.65 ± 12.87 vs. 51.80 ± 14.31, p = 0.006) and trial-to-trial transfer capabilities (54.82 ± 25.29 vs. 87.21 ± 8.99, p < 0.001), impaired face recognition abilities reflected in lower correct answer proportion (0.66 ± 0.13 vs. 0.83 ± 0.09, p < 0.001), and impaired visuo-spatial memory, when compared to controls (89.42 ± 55.42 vs. 49.37 ± 16.57, p < 0.001). It was specifically observed that higher rates of non-list words were recorded in WLM in the schizophrenia patients group.

The study supports the current data which state that working memory deficits in schizophrenia are consistent, stable and comprehensive, which is particularly relevant for the social functioning of schizophrenia patients. Occurrence of non-list words in auditory memory may explain the mechanism of paranoid delusions.