Relationship between Inner-Ear Fluid Pressure and Semicircular Canal Afferent Nerve Discharge

摘要: The present study was designed to determine (1) the transcupular fluid pressure (ΔP) generated across semicircular canal cupula in response sinusoidal head rotation, (2) translabyrinthine dilational (P0) membranous labyrinth an increase endolymph volume (hydrops), (3) afferent nerve discharge patterns by these distinct stimuli and, (4) threshold values of ΔP and P0 required elicit neural responses. experimental model oyster toadfish, Opsanus tau. Micromechanical indentation horizontal (HC) duct utricular vestibule used simulate rotation injection. Single-unit spike trains within ampulla, on both sides cupula, were recorded simultaneously. averaged 0.013 Pa per 1°/s angular velocity 0.2 1 nL most responsive afferents had a sensitivity 10-3 5 × 10-2 based modulation criterion impulse/s cycle for 2 Hz stimuli. Neural expected basis transverse cupular hair bundle deflections. Analysis mechanics end organ, neuronal projections into crista, individual firing indicates that resulted from pressure-induced distension ampulla led nonuniform deformation pattern This explanation is consistent with predictions finite element organ. Results have implications regarding role motion transduction under transient hydropic conditions.