Head Direction System Research Articles

A coupled attractor model of the rodent head direction system

Head direction (HD) cells, abundant in the rat postsubiculum and anterior thalamic nuclei, fire maximally when the rat's head is facing a particular direction. The activity of a population of these cells forms a distributed representation of the animal's current heading. We describe a neural network model that creates a stable, distributed representation of head direction and updates that representation in response to angular velocity information. In contrast to earlier models, our model of the head direction system accurately tracks a series of actual rat head rotations, and, using biologically plausible neurons, it fits the single-cell tuning curves of real HD cells recorded from rats executing those same rotations. The model makes neurophysiological predictions that can be tested using current technologies.

Physiology of peripheral neurons innervating semicircular canals of the squirrel monkey. II. Response to sinusoidal stimulation and dynamics of peripheral vestibular system.

A CENTRAL PROBLEM in vestibular physiology has been the elucidation of the dynamics of the peripheral vestibular apparatus. Following the development of the torsion-pendulum model by Steinhausen (24, 25), many efforts have been directed toward the determination of the time constants of the model. That the model, itself, might not adequately describe the transfer characteristics of the peripheral system has seldom been questioned. Further, the procedures employed to estimate the time constants have had their drawbacks. The dynamics of the system have sometimes been deduced from hydrodynamic principles (5, 6, 15, 17, 22, 23). Such an analysis permits the inference of only some of the relevant variables. In the torsionpendulum model, it will be recalled, the angular deflection of the cupula g(t) is related to the angular acceleration a(t) by the equation

Inhibition of central vestibular neurons from the contralateral labyrinth and its mediating pathway.

Inhibition of central vestibular neurons from the contralateral labyrinth and its mediating pathway.