Aberrant anterior cingulate activation in obsessive-compulsive disorder is related to task complexity

Area of Science:

• Neuroscience
• Cognitive Psychology
• Psychiatry

Background:

• Growing evidence suggests working memory (WM) deficits in obsessive-compulsive disorder (OCD).
• Neural correlates of these WM deficits in OCD are inconsistent.
• The impact of cognitive load on WM performance and brain activation in OCD remains unclear.

Purpose of the Study:

• To investigate the neural underpinnings of working memory deficits in OCD.
• To examine how varying cognitive demands affect brain activation in OCD patients.
• To compare brain activation patterns during a working memory task between OCD patients and healthy controls.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was employed.
• A parametric verbal n-back task was administered.
• The study included 21 medication-free inpatients with OCD and 21 matched healthy volunteers.

Main Results:

• No significant activation differences were observed between groups under low cognitive load.
• OCD patients displayed reduced activation in the dorsal anterior cingulate cortex (dACC) as task demands increased.
• Healthy controls showed a linear increase in dACC activation with task demands, which was absent in OCD patients.

Conclusions:

• The findings highlight the critical role of the anterior cingulate cortex in OCD.
• Cognitive demand significantly influences task-related brain activation in individuals with OCD.
• These results underscore the importance of considering task demands and processes in understanding OCD pathophysiology.