Numerous studies indicate that ACh plays an important and diverse role in the regulation of cortical activity over multiple timescales. The precise function of ACh on any given circuit also greatly depends on the specific expression patterns of nAChRs and mAChRs, as well as the temporal dynamics of ACh concentration in the extracellular space. Neocortical ACh function has been linked to control of circuits underlying attention, cue detection, and memory (Hasselmo and Sarter, 2011). The primary cholinergic input to the cerebral cortex comes from the BF complex, and particularly from substantia innominata of the the nucleus basalis of Meynert (Mesulam, 1995) though the latter remains debated (Zaborszky et al., 1999). Cholinergic terminals are distributed throughout the cortex, with more dense projections in superficial layers (Mesulam, 1995).
