Fig. 5.

Population activity of NAc neurons during feeding (licking; left) and SWS (right). Shown are all the significant responses of 187 neurons, each normalized to Z scores (far right), centered around the onset (CE) and termination of licking clusters (CE) or the onset (QW→SWS) or termination (SWS→QW) of SWS bouts. Both of these onset times are indicated by vertical white lines (time = 0 s). The response types are referenced to the feeding (licking) state. The dashed white lines separate subcategories, and solid horizontal black lines identify the population of each category of inactive, active, and SWS-off and SWS-on neurons. It can be seen that inactive responsive cells can exhibit “on” or “off” responses in SWS or be nonresponsive (inactive only). The same is evident for active cells, whose response to SWS can be excitatory (on), inhibitory (off), or unresponsive. Finally, there are other populations of neurons that are unresponsive to feeding but can be inhibited (SWS-off only) or excited (SWS-on only) during SWS. For each subcategory, neurons were sorted as a function of their putative cell type (see Fig. 7 for more details). The color bar at far left indicates the putative cell type: blue, pMSN; red, putative choline acetyltransferase interneuron (pChAT); black, pFSI; green, unidentified cell type.