Light photomicrograph of the cochlear upper base (~18 kHz region) in two example mice receiving Saline + Noise (A–C) or KM + Noise (D–F). No features clearly and consistently distinguished mice by treatment group; Organ of Corti (A, D), spiral ganglion cells (SpG in B, E), and lateral wall (C, F) appeared similar in each group. Raised particles in C, F are processing artifacts. StV Stria vascularis; SpL spiral ligament; C capillaries; Bn bone.