Primate basal ganglia activity in a precued reaching task: preparation for movement

Area of Science:

• Neuroscience
• Motor Control
• Primate Behavior

Background:

• The basal ganglia play a crucial role in motor control and action selection.
• Understanding neuronal activity during movement preparation is key to deciphering motor control mechanisms.

Purpose of the Study:

• To investigate neuronal activity in the primate basal ganglia (putamen, caudate nucleus, globus pallidus) during movement preparation.
• To examine how advance information (precues) and delay intervals affect this preparatory activity.

Main Methods:

• Single-cell activity recording from the putamen, caudate nucleus, and globus pallidus in primates.
• A precued reaching movement task with varying levels of advance information and delay intervals.
• Analysis of neuronal firing patterns during the preparatory period before movement execution.

Main Results:

• Significant preparatory neuronal activity was observed in 30-31% of neurons across the studied basal ganglia structures.
• Preparatory activity was stronger and more temporally linked to movement initiation in the putamen compared to the caudate nucleus.
• While advance information did not significantly alter preparatory activity, directional selectivity was noted in a subset of neurons when precues provided directional information.

Conclusions:

• Basal ganglia neuronal activity during the preparatory period contributes to motor readiness, influencing reaction times.
• The intensity of preparatory activity is modulated by the duration of the delay interval, suggesting a temporal integration process.
• These findings highlight the basal ganglia's role in preparing for and executing goal-directed movements.