Figure 2.

Schematic of the wave of engram recruitment in the NAcore induced by a cocaine cue. We hypothesize that the cocaine/cue-associated ensemble, formed during cocaine self-administration, undergoes transient synaptic potentiation (t-SP) that spreads through the NAcore due to NO production and activation of MMPs (see figure 1). The local recruitment of a larger number of MSNs reduces the size of the ensemble activated by a sucrose cue, thereby promoting drug seeking over sucrose seeking.

Cocaine-selective cells in red, sucrose-selective cells in blue, cells showing overlapping activity for cocaine and sucrose in purple, non-responding cells in grey, cells activated during reinstatement in orange. Phases A and B based on Cameron & Carelli, 2012.