Reevaluation of the contribution of the basal forebrain cholinergic system to memory.

In this review the relationship between the basal forebrain cholinergic system and memory is explored. It appears that different components of the cholinergic forebrain system [e.g., medial septum (MS) and nucleus basalis magnocellularis (NBM)] have dissociable mnemonic functions in animals, and comparable mnemonic functions in humans are dissociable as well. Furthermore, the cholinergic input from MS to the hippocampus and NBM to basolateral amygdala appear to be of critical importance in mediating mnemonic function. Finally, comparable impairments in memory function are found in basal forebrain-damaged rats and patients with dementia of the Alzheimer's type, suggesting that there might be important homologies between animals and humans in terms of basal forebrain-mediated memory function.