Reduced directed forgetting for negative words suggests schizophrenia-related disinhibition of emotional cues

Abstract

Several psychological and neurobiological models imply that patients with schizophrenia (SCZ) are more inclined to utilize emotional cues as response determinants to the detriment of more task-appropriate cognitive or contextual cues. However, there is a lack of behavioural data from human clinical studies to support this assertion. Therefore, it is important to evaluate the performance of persons with SCZ using tasks designed to index the resolution between competing emotional and cognitive determinants of goal-directed behaviour. The current study employed a list-method, emotional directed-forgetting (DF) paradigm designed to invoke inhibitory mechanisms necessary to override emotional memory enhancement for successful task completion. Four psycholinguistically matched lists were constructed that were comprised of five negative, five positive, and five neutral words. Compared with healthy controls, individuals with SCZ showed a reduced DF effect overall. When broken down according to valence, this effect was only observed for negative words, which, in turn, resulted from reduced forgetting of list 1 words following the forget cue. These results indicate that individuals with SCZ were less able to engage strategic inhibitory mechanisms for the purpose of overriding recall of negative stimuli when tasks demand call for such action. Thus, our data support the theoretical assertion that SCZ patients have difficulty utilizing cognitive or contextual cues as determinants of goal-directed behaviour in the face of countermanding emotional cues.