A model of head direction and landmark coding in complex environments
Fig 4
aLB cells show high encoding capacity across multiple environments.
(A) The agent is exposed to 10 environments sequentially (top) with feature-specific visual input signals due East in Env. I (bottom). Sceneries contain ‘red’ and ‘blue’ cues, common to all environments, and a ‘green’ cue, at an orientation relative to the other two cues that change between environments. (B) Global representations of aLB cells with local weights tested on corresponding sceneries. Titles for each plot refer to the corresponding environment in (A), along with the total number of highly activated aLB cells in brackets. The ’intermediate’ plots provide aLB cell activity based on weights after the first exposure in each individual environment. The ‘final’ plots provide aLB cell activity based on weights after the learning in all 10 environments is complete. See Fig 2D for illustrations. Warmer colors represent higher firing rates. (C) IoU similarity maps measuring the similarity of two sets of aLB cell firing patterns when tested on specific sceneries. Axes refer to environments, with 1 as the earliest (i.e. Env. I). The left column provides IoU maps based on ‘intermediate’ weights. The middle column provides IoU map based on ‘final’ weights. The right column provides the IoU index (y-axis) between the first exposure and the end of learning tested on each scenery (x-axis). Green colors represent higher IoU, of which the maximum is 1. Abbreviations: HD: head direction; Env.: Environment; Ego.: Egocentric; aLB: abstract landmark bearing; IoU: Intersection over Union; f: firing rate.