Similar to the inhibition observed in the PFC, the hippocampus is a sensitive target of alcohol’s actions in the brain. Defined, in part, by its characteristic trisynaptic circuit, human and animal studies have demonstrated that the hippocampus is critical for spatial memory [reviewed in Ref. (51)], context discrimination (52), pattern separation (53), and time-sensitive memories (54). A critically unique region of the hippocampus, the dentate gyrus (DG), contains neural stem cells that continue to divide and primarily generate functional neurons into adulthood in nearly all mammalian species (55) and have proved critical for pattern separation functionality (56). Beyond its role in the previously described functions, the hippocampus plays a critical role in emotional and stress regulation (57), critical components to the development and cyclical nature of addiction (58). In human subjects, hippocampal function is typically assessed as contextual memory or episodic memory, both of which have been shown to be impacted during acute alcohol exposure (49, 59).
