The term medioventral periolivary nucleus refers to one of four cell groupsi identified by Nissl stain in the periolivary region of the macaque. The others are the lateroventral periolivary nucleus, the superior paraolivary nucleus, and the dorsal periolivary region ( Paxinos-2009a ). It is also identified by some authors in the rat ( Paxinos-2009b ) and the mouse ( Paxinos-2001 ). Functionally it is part of the subcortical auditory system ( Swanson-2004 ).