Which nucleus is involved in hemiballismus?
A. Globus pallidus
B. Caudate nucleus
C. Substantia nigra
D. Subthalamic
Answer. D
Solution. The correct answer is Subthalamic nucleus. Hemiballismus is a type of movement
disorder characterized by wild, flailing movements of one limb. It is caused by damage to the
subthalamic nucleus, a small nuclei located in the diencephalon, which is involved in regulating
movement. When the subthalamic nucleus is damaged, it can disrupt the normal balance of
excitatory and inhibitory signals to the basal ganglia, leading to the uncontrolled movements
seen in hemiballismus