Fig 3. aLB cells exhibit robustness against unstable or ephemeral cues, and can incorporate novel cues.

(A) Single environment (same as Fig 1B) with the ‘blue’ cue moving along the cylinder with 90 deg/s anticlockwise during training (left). Global representation of aLB cells tested on the unstable scenery with ‘blue’ cue moving by 90 deg/s anticlockwise (middle, ε_aLB = 0) and the stabilised scenery with ‘blue’ cue fixed after learning has stopped (right, ε_aLB = 0.5). (B) Single environment (same as Fig 1B) with the ‘blue’ cue teleporting to a random position on the cylinder every 10 seconds (left). Global representation of aLB cells tested on the unstable scenery with ‘blue’ cue teleporting every 10 seconds (middle, ε_aLB = 0) and the stabilised scenery with ‘blue’ cue fixed after learning has stopped (right, ε_aLB = 0.5). (C) Two sceneries (within the same environment) with the ‘red-blue’ scenery (Sc. I) and a ‘red-blue-green’ scenery (Sc. II). The agent stays in each scenery for 400 seconds (once from Sc. I to Sc. II and back to Sc. I), with feature-specific visual input signals in Sc. II (bottom). (D) Following the learning phase, the model is tested on the ‘red-blue’ scenery (i.e. Sc. I, top), the ‘red-blue-green’ scenery (i.e. Sc. II, middle), and the ‘green’ scenery (i.e. Sc. II with ‘red-blue’ scenery excluded, bottom). Stable unimodal aLB representations emerge in all cases (also see S3 Fig), with different sets of active cells in Sc. I vs. Sc. II (S4 Fig). Warmer colors represent higher firing rates of aLB cells. Abbreviations: HD: head direction; aLB: abstract landmark bearing; ego.: egocentric.