Sensory information passes both the auditory and the limbic systems by the means of medial geniculate nucleus (MGN), a small oval mass that protrudes slightly from the underside of the thalamus, a big double-lobed structure buried under the cerebral cortex. Before the signal can travel on, however, it passes through another nearby structure called the thalamic reticular nucleus (TRN), which evaluates whether or not it should be passed on.
