The subthalamic nucleus contributes causally to perceptual decision-making in monkeys

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Computational Neuroscience

Background:

• The subthalamic nucleus (STN) is integral to basal ganglia function, impacting motor and cognitive processes.
• Its precise role in decision-making, particularly with uncertain evidence, remains incompletely understood.

Purpose of the Study:

• To investigate the causal and computational roles of the STN in visual-saccadic decisions using noisy evidence.
• To test theoretical predictions regarding specific STN contributions to decision-making.

Main Methods:

• Employed single-unit recording in the STN of healthy monkeys during a visual-saccadic task.
• Utilized electrical microstimulation of the STN to observe effects on behavior.
• Analyzed neuronal activity patterns and behavioral choices in response to varying evidence.

Main Results:

• Identified distinct STN neuronal subpopulations with activity patterns linked to predicted functions.
• Microstimulation modulated behavioral choices and response times, indicating STN involvement in decision bounds.
• Demonstrated STN contributions to evidence accumulation and non-perceptual aspects of the decision process.

Conclusions:

• The STN plays multiple, multifaceted roles in supporting higher brain functions, including decision-making.
• Findings clarify the STN's contribution to an 'accumulate-to-bound' decision framework.
• Provides novel insights into the neural mechanisms underlying evidence-based choices.