A model of the rodent head direction system

Head direction cells in the postsubiculum (PoS, also known as dorsal presubiculum) were first described by Ranck et al. [10]. In subsequent work, Taube et al. [14] characterized these cells as having triangular tuning curves: the firing rate drops off linearly from a peak at the preferred direction until it reaches a baseline value. Taube et al. [15] report that PoS cells typically have baseline-to-baseline tuning curve widths of 100°. Similar cells have been found in the anterior thalamic nuclei (ATN) [4, 6, 13]. See Figure 1(b) for a sample PoS tuning curve. These curves can also be modeled very closely by Gaussians with an average standard deviation of approximately 66° [4, 18].