Figure 1.
Origin and distribution of efferent fibers of the right and left OCB in the superior olivary complex, to the right cochlea. Percentages (cat data) (Warr, 1978) indicate the proportion of crossed and uncrossed fibers projecting from each medial OCB (MOCB) and lateral OCB (LOCB) to inner hair cells (IHCs) and outer hair cells (OHCs) of the right cochlea. Because this schematic represents only innervation of the right cochlea, only the crossed fibers from the left OCB and uncrossed fibers from the right OCB are shown. MOCB efferent fibers predominantly terminate at the base of the OHCs, whereas LOCB efferent fibers predominantly project to the dendritic processes of the Type I spiral ganglion auditory neurons that innervate IHCs (Spangler and Warr, 1991). Top right, Medial olivocochlear response (MOCR) magnitude as a function of time after stimulus onset. Typical MOCR rise and decay time constants (human otoacoustic emission data) (Backus and Guinan, 2006) are also shown (τr and τd, respectively).