Visual exploration differences during relational memory encoding in early psychosis

Abstract

Relational memory, or the ability to form contextual associations among items encountered closely in time, is impaired in schizophrenia. The ability to bind items into a relational memory is dependent on the hippocampus, a region that is abnormal in schizophrenia. However, the hippocampus is also involved in exploratory behavior, leaving open the question whether relational memory deficits in schizophrenia are due to failure of relational binding or diminished visual exploration of individual items during encoding. We studied visual exploration patterns during the encoding of face-scene pairs in 66 healthy control subjects and 69 early psychosis patients, to test the hypothesis that differences in visual exploration during the encoding phase can explain task accuracy differences between the two groups. Psychosis patients had lower explicit test accuracy and were less likely to transition from mouth to eyes during encoding. The visual exploration pattern differences between groups did not mediate the relationship between group and explicit test accuracy. We conclude that early psychosis patients have an abnormal pattern of binding items together during encoding that warrants further research.