GENERAL HISTOLOGY

Detailed explanation-1: -The substantia nigra and subthalamic nucleus are not anatomical constituents of the basal ganglia, but functionally they belong together. Instead, the substantia nigra is located in the midbrain while the subthalamic nucleus is a part of the subthalamus, which is found in the diencephalon ventral to the thalamus.

Detailed explanation-2: -Subthalamic nucleus The subthalamic nuclei (STN), also known as Luys’ bodies, are small biconvex paired structures located within the subthalamus. The subthalamic nucleus is not an anatomical part of the basal ganglia.

Detailed explanation-3: -The thalamus, subthalamus, and substantia nigra (SN) are not a part of basal ganglia but serve essential functions for the network. The motor system controlled by basal ganglia is made of corticobulbar and subcortical structures, the gray matter of the spinal cord, cerebellum, and efferent nerves.

Detailed explanation-4: -The basal ganglia are a cluster of subcortical nuclei deep to cerebral hemispheres. The largest component of the basal ganglia is the corpus striatum which contains the caudate and lenticular nuclei (the putamen, globus pallidus externus, and internus), the subthalamic nucleus (STN), and the substantia nigra (SN).

Detailed explanation-5: -The structures generally included in the basal ganglia are the caudate nucleus, putamen, and globus pallidus in the cerebrum, the substantia nigra in the midbrain, and the subthalamic nucleus in the diencephalon.