Subthalamic nucleus stimulation reverses mediofrontal influence over decision threshold

Area of Science:

• Neuroscience
• Cognitive Psychology
• Decision Making

Background:

• The medial prefrontal cortex (mPFC) is involved in effortful behavioral control.
• The subthalamic nucleus (STN) is hypothesized to act as a brake on cortico-striatal pathways during decision conflict.

Purpose of the Study:

• To investigate the roles of mPFC and STN in regulating decision-making under conflict.
• To examine how STN function influences impulsive choice.

Main Methods:

• Utilized the drift diffusion model of decision making.
• Measured medial prefrontal cortex (mPFC) activity using EEG theta power (4-8 Hz).
• Investigated the effects of subthalamic nucleus (STN) deep brain stimulation in Parkinson's disease patients and performed intracranial recordings of the STN area.

Main Results:

• Increased mPFC activity correlated with a higher decision threshold for evidence accumulation during high-conflict trials.
• Deep brain stimulation of the STN reversed this relationship, leading to impulsive choices.
• Increased STN activity in slow frequency bands (2.5-5 Hz) was observed during high-conflict decisions.

Conclusions:

• Trial-to-trial mPFC activity modulates decision thresholds based on conflict levels.
• STN activity, particularly in slow frequencies, appears crucial for inhibiting impulsive choices and regulating decision processes within cortico-basal ganglia circuits.