How the mammalian brain achieves accurate tracking of head direction at different turning-velocities?

Arseny Finkelstein, Hervé Rouault, Sandro Romani, Nachum Ulanovsky. Dynamic control of cortical head-direction signal by angular velocity. doi: https://doi.org/10.1101/730374

Abstract
The sense of direction requires accurate tracking of head direction at different turning-velocities, yet it remains unclear how this is achieved in the mammalian brain. Here we recorded head-direction cells in bat dorsal presubiculum and found that, surprisingly, the head-direction signal in this cortical region was dynamically controlled by angular velocity. In most neurons, a sharp head-direction tuning emerged at some angular velocity, but was absent at other velocities – resulting in a 4-fold increase in head-direction cell abundance. The head-direction tuning changed as a function of angular velocity primarily via a redistribution of spikes between the neuron’s preferred and null directions – while keeping the average firing-rate constant. These results could not be explained by existing ‘ring-attractor’ models of the head-direction system. We propose a novel recurrent network model that accounts for the observed dynamics of head-direction cells. This model predicts that the new classes of cells we found can improve the sensitivity of the head-direction system to directional sensory cues, and support angular-velocity integration.”

Arseny Finkelstein, Hervé Rouault, Sandro Romani, Nachum Ulanovsky. Dynamic control of cortical head-direction signal by angular velocity. doi: https://doi.org/10.1101/730374