Subthalamic nucleus stimulation affects striato-anterior cingulate cortex circuit in a response conflict task: a PET...

Area of Science:

• Neuroscience
• Cognitive Neurology
• Neurosurgery

Background:

• The subthalamic nucleus (STN) is traditionally viewed as a motor control relay.
• Its role in cognitive networks remains less understood.
• Deep brain stimulation (DBS) of the STN offers a method to study its non-motor functions in Parkinson's disease (PD).

Purpose of the Study:

• To investigate the influence of STN DBS on cognitive networks, specifically response conflict processing.
• To examine changes in regional cerebral blood flow (rCBF) during a cognitive task with and without STN stimulation in PD patients.

Main Methods:

• Positron Emission Tomography (PET) was used to measure rCBF.
• Parkinson's disease patients were studied ON and OFF bilateral STN DBS.
• A Stroop task, assessing response conflict, was administered.

Main Results:

• STN stimulation led to impaired performance on the Stroop task, indicated by prolonged reaction times.
• This impairment was associated with decreased activation in the right anterior cingulate cortex (ACC) and right ventral striatum.
• Increased activation in the left angular gyrus suggested difficulties in inhibiting habitual responses during STN stimulation.

Conclusions:

• STN DBS modulates non-motor basal ganglia-thalamocortical circuitry involved in response conflict.
• Reduced activation within the ACC circuit during STN stimulation correlates with worsened cognitive performance.
• Impaired ACC circuit function may explain subtle cognitive deficits observed with STN DBS.