Verbal and visual-spatial memory impairment in youth at familial risk for schizophrenia or affective psychosis: a pilot study.

BACKGROUND: Schizophrenia and affective psychoses share several common biological origins, particularly genetic susceptibility. Kraepelin posited that differing clinical expressions in these disorders reflect different etiopathologies. We tested a neuropsychological component of this hypothesis by evaluating verbal memory and visual memory performance in nonpsychotic youth at familial risk for psychosis, taking into account contributions to memory dysfunction including executive processing and psychopathology.
METHODS: Teenage and young adults (ages 13-25) at familial high-risk (FHR) for schizophrenia (HR-SCZ, n=41) or affective psychosis (HR-AFF, n=24) were compared to community controls (CC, n=54) on verbal (Miller-Selfridge Context Memory) and visual (Rey-Osterrieth Complex Figure) memory tests in which the roles of strategy and contextual processing on distinct recall domains could be assessed. Effects of psychopathology, vigilance and working memory were investigated to determine their influence on memory performance.
RESULTS: HR-AFF and HR-SCZ exhibited similarly impaired memory profiles and elevated levels of psychopathology compared to CC. HR-SCZ were significantly impaired on both verbal memory and visual-spatial memory, while HR-AFF in verbal memory only. However, effect sizes, in the medium range, were largely comparable between the two HR groups. Deficits in verbal recall and in visual memory organization remained significant after adjustment for confounders.
CONCLUSIONS: Youth at FHR for psychosis present relatively common memory deficits across both visual-spatial and verbal modalities that are not explained by current psychopathology, vigilance or working memory deficits. Deficits in organizing information to be recalled represent a promising trait of psychosis vulnerability.