Three-Row Stereocilia Model Predicts Mammalian Hair Bundle Behavior

The study presents a mathematical model of outer hair cell (OHC) hair bundles (HBs) in mammals, focusing on the three-row stereocilia configuration. This model incorporates nonlinear adaptive gating mechanisms, kinematics, and viscoelastic mechanics to replicate experimental responses to fluid-jet and stiff probe stimulations. It successfully predicts mechanical creep and dual timescales of mechano-electric transducer (MET) current adaptation, highlighting the stimulus-dependence of these responses. The findings provide insights into the functional significance of the three-row stereocilia arrangement, explaining its prevalence in mammalian HBs and its role in auditory function and adaptation.