Figure 5. Disconnection (‘re‐weighting’) of spatially unstable sensory cues from the head direction cell attractor network .

A, top, landmarks become associated with activation of the HD ring attractor by Hebbian re‐weighting, forming strong connections (red arrows). Bottom, when a landmark moves, the existing connection with the ring attractor weakens (dotted arrow). B, how unstable landmarks could become disconnected by Hebbian re‐weighting. When a given set of sensory neurons has activity reliably associated with the same set of head direction neurons (left‐hand panels), connections become stronger by Hebbian associativity. If the cues are spatially unstable (right‐hand panels) and are associated with different parts of the attractor network on different trials, the connections will weaken by an anti‐Hebbian mechanism (Hebb–Stent rule) and connections will lose strength.