in the hippocampus leading to altered ACh signaling in this structure (Nijholt et al., 2004). There is currently no consensus on how these cholinergic actions converge to regulate the output of the hippocampus in response to stress, although one possibility is that ACh is critical for regulating theta oscillations, and the concurrent effects of mAChRs and nAChRs on excitatory and inhibitory transmission serve to regulate rhythmic activity (Drever et al., 2011; Fisahn et al., 1998). Although theta rhythms are thought to be critical for memory encoding, disturbance of hippocampal rhythms may also contribute to mood disorders (Femenia et al., 2012).
