Working memory dysfunction in delusional disorders: an fMRI investigation

Area of Science:

• Neuroscience
• Psychiatry
• Cognitive Psychology

Background:

• Delusional disorder (DD) is a rare psychiatric condition with limited research on its cognitive characteristics.
• Working memory function in DD remains understudied, necessitating further investigation.

Purpose of the Study:

• To investigate alterations in brain activity during working memory tasks in patients with delusional disorder using functional magnetic resonance imaging (fMRI).
• To compare brain activation patterns between individuals with DD and healthy controls.

Main Methods:

• A case-control study involving 9 patients with DD and 9 matched healthy controls.
• Participants performed 0-back and 2-back tasks during fMRI scans.
• DD diagnosis was confirmed using the Structured Clinical Interview for DSM-IV Axis I.

Main Results:

• Patients with DD exhibited reduced activation in the left dorsolateral prefrontal cortex compared to controls.
• Increased neural activation was observed in the temporal gyrus (superior, middle, inferior), posterior cingulate gyrus, amygdala, and fusiform gyrus in patients with DD.
• These differences were evident during working memory task performance.

Conclusions:

• Delusional disorder is associated with functional brain alterations in prefrontal, temporal, and limbic regions, particularly during working memory tasks.
• Findings suggest deficient functioning in temporal and limbic areas, consistent with prior research.
• Prefrontal dysfunction in DD resembles patterns observed in schizophrenia.