Figure 4.

Equilibrium distribution of synaptic activity, and the impact of visual inputs disrupting equilibrium from Wright and Bourke (2013). Top: equilibrium disposition of saturated and sensitive synapses. Black circles represent cell bodies and dendrites. Synapses are indicated as saturated (solid) or sensitive (dashed) terminations of axons. Reciprocal connections between α-patches (patchy connections) form the hexagonal array. (Other connections, although shown as unidirectional, are also reciprocal.) A representative pair of connections from α-cells to the β-patch is displayed in the upper-and lower-aspects of the figure. At the center of the figure, saturated and sensitive synapses show the network's analogy to a Möbius-strip within a β-patch (macrocolumn). To the right, representative links from the central macrocolumn to cells at homologous positions in neighboring macrocolumns. Bottom: exposed to strong transient signals conveyed over the superficial patch system, summing with direct visual inputs conveyed to the cRF, the equilibrium configuration breaks down. The green bar represents the field of excitation of cells by the contextual signals, within which cells also directly excited in the cRF, fire at high rates.