metathalamus /met′əthal″əməs/ [Gk, meta + thalamos, chamber] , one of five parts of the diencephalon, composed of a medial geniculate body and a lateral geniculate body on each side. The medial geniculate body acts as a relay station for nerve impulses between the inferior brachium and the auditory cortex. The lateral geniculate body is a superficial oval bulge at the posterior end of the thalamus, which accommodates the terminal ends of the fibers of the optic tract. Relay cells project to the visual cortex. Compare epithalamus, hypothalamus, subthalamus. −metathalamic, adj.
