Fig. 5.

Model comparison. A: overall goodness of fits of all models considered in this study. Error bars indicate the standard error, based on a bootstrap procedure. B: modulation of head direction (HD) responses as a function of tilt angle when facing the cell’s preferred direction (PD). Dots: median firing rate in Shinder and Taube’s (2019) study as a function of tilt angle, when facing the cell PD, and across all manipulations. Solid/broken cyan/blue lines: firing rate predicted by models during manipulations 4, 6, and 7 where the head tilts when facing the PD, assuming that 1) azimuth is encoded in a yaw-only (YO; cyan) or tilted azimuth (TA; blue) frame and 2) HD firing decreases continuously (solid line) or abruptly at 90° tilt (i.e., hemitorus/ellipsoid model, broken line). Note that the TA and YO (cyan versus blue) models yield identical predictions during this motion. Avg. Norm., average normalized.