Canonical Cortical Circuit Model Explains Rivalry, Intermittent Rivalry, and Rivalry Memory
Fig 10
u1-u2 bifurcations across static symmetric external drive S for system with nonlocal fatigue.
The pitchfork bifurcation for arbitrarily low input provides the asymmetry necessary for intermittent rivalry and rivalry memory. It allows for memory of the last dominant state by maintaining asymmetry for very small (background) input (Soff) (Soff = 0.001). A shift in the asymmetric state in the off-state by a build-up of fatigue due to larger S in the on-state (Son) eventually leads to a shift in dominance. Although not drawn, the limit cycle extends to the red pitchfork terminating in a SNIC. A smoothed threshold was used to generate the plot. For actual simulations we used a hard threshold and zero input gives symmetric, zero activity.