Depression, avolition, and attention disorders in patients with schizophrenia: associations with verbal memory efficiency.

The authors undertook a study of the clinical correlates of verbal memory deficits in schizophrenia. The first purpose was to replicate the finding of a significant association between depression and impairment in the deep encoding memory processes. The second purpose was to test the hypothesis that certain clinical symptoms--avolition, disorders of attention--also play a role in verbal memory impairment, distinct from a global negative symptomatology score. Forty-one patients with schizophrenia underwent a memory task including forward digit span and learning lists of words with different levels of semantic organization. Regression analyses revealed that the depression score was associated with the total number of recalled words, whereas the global negative symptom score was not. Depression score was not associated with the forward digit span, a measure of superficial serial encoding processes. An analysis of individual symptoms from the Scale for the Assessment of Negative Symptoms (SANS) indicated that avolition was associated with several memory scores, suggesting a pervasive effect of this symptom. Attention disorders were associated with impaired efficiency in serial learning, but not with word recall efficiency. It is suggested that more consideration should be given to depression and motivation in the investigation of cognitive impairment in schizophrenia, as well as in cognitive remediation strategies.