The vestibular-ocular and vestibulo-spinal network provides the ability to hold gaze fixed on an object during head movement. Within that network, the second-order neurons of the medial vestibular nucleus (MVNn) compute internal representations of head movement velocity in the horizontal plane. In vivo, these neurons can be classified as either tonic (type A) or phasic (type B), depending on their responses to head accelerations. In this study we have investigated to what extend the MVNn intrinsic membrane properties, could contribute to their dynamics. Biophysical models of the two categories were examined under ramp, step, sinusoidal and random depolarizing stimulations, Two factors were found major: the activation of the delayed potassium current and the rate of calcium flux.
展开▼
