Motor control in basal ganglia circuits using fMRI and brain atlas approaches

TLDR

The study investigates how motor, premotor, and associative basal ganglia regions encode movement complexity and frequency. Twelve right‑handed volunteers performed audio‑paced finger‑tapping tasks of varying complexity and frequency while 3‑T EPI BOLD fMRI was recorded, and the resulting activation maps were coregistered onto a 3‑D post‑mortem brain atlas. Activation patterns revealed that posterior putamen and sensorimotor cortex respond to frequency alone, premotor areas, anterior putamen, and ventral posterolateral thalamus respond to both frequency and complexity, while rostral frontal regions, caudate, subthalamic nucleus, and ventral anterior/ventrolateral thalamus respond mainly to complex and high‑frequency tasks, demonstrating distinct roles of basal ganglia circuits in motor processing.

Abstract

In this study, we examined how the motor, premotor and associative basal ganglia territories process movement parameters such as the complexity and the frequency of movement. Twelve right-handed volunteers were studied using EPI BOLD contrast (3 T) while performing audio-paced finger tapping tasks designed to differentiate basal ganglia territories. Tasks varied movement complexity (repetitive index tapping, simple sequence of finger movements and complex sequence of 10 moves) and frequency (from 0.5 to 3 Hz). Activation maps were coregistered onto a 3-D brain atlas derived from post-mortem brains. Three main patterns of activation were observed. In the posterior putamen and the sensorimotor cortex, signal increased with movement frequency but not with movement complexity. In premotor areas, the anterior putamen and the ventral posterolateral thalamus, signal increased regularly with increasing movement frequency and complexity. In rostral frontal areas, the caudate nucleus, the subthalamic nucleus and the ventral anterior/ventrolateral thalamus, signal increased mainly during the complex task and the high frequency task (3 Hz). These data show the different roles of motor, premotor and associative basal ganglia circuits in the processing of motor-related operations and suggest that activation can be precisely located within the entire circuitry of the basal ganglia.