Tonotopic organization

Classical. Von Békésy traveling wave; basal BM responds to high f, apical to low f. Set primarily by BM width/stiffness gradient + TM mechanics. Active. Cochlear amplifier (OHC electromotility + Cochlear Amplifier as Hopf Oscillator) sharpens tuning by ~40 dB. Stereocilia contribution. Length, bundle count, tip-link tension, gating-spring stiffness all scale with f (see Tip-Link Tension Tonotopic Gradient). STRC relevance. Stereocilin loss degrades bundle coherence → tonotopic sharpness drops. ABR threshold elevation is frequency-dependent (mid-high frequencies most affected in Misha’s audiogram).

Connections