Fig. 4: Balanced Integration Score (BIS) data from visuospatial working memory task, comparing placebo (PLAC) to aripiprazole (ARI) in fixed location control trials (left) and variable location trials (right), with separate coloured lines for delay conditions.

The BIS measures accuracy adjusted for reaction time; lower scores indicate poorer performance. Values are estimated marginal means ± SEM from generalised linear mixed model. The main effect of treatment condition showed that aripiprazole led to poorer performance compared to placebo overall. Analysis of task effects showed poorer performance in variable location trials compared to fixed location control trials, and poorer performance in distractor trials compared to delay and no delay trials. There was a treatment condition * trial difficulty interaction, indicating that this was due to aripiprazole specifically impairing performance in variable location trials and not in fixed location trials. Model r² = 0.67.