Figure 1. Major anatomical structures of the motor system. This figure shows a human brain, reconstructed from magnetic resonance imaging techniques, in lateral and horizontal views. In the lateral view, the frontal pole of the cerebral hemisphere is on the left, so that the left hemisphere is in view. The location of the motor area of the cerebral cortex is indicated. The medulla and pons are parts of the brainstem; the midbrain lies above the pons, but this part of the brainstem is obscured from view by the cerebrum. The spinal cord continues from the brainstem and is cut off here at about the midcervical (neck) level. The cerebellum sits atop the brainstem and below the posterior part of the cerebrum. The line A-P shows the placement of a horizontal section through the cerebrum. The section in the lower part of the figure shows the internal structures revealed when looking down on the brain through this section. Deep within the cerebrum we can see the basal ganglia, which lie anterior and lateral to the thalamus.