Memory cholinergic system

Muscarinic receptors have modulatory effects on numerous other neurotransmitters in the brain (van der Zee and Luiten 1999). Of particular interest are interactions between glutamate and cholinergic systems in learning and memory (Aigner 1995). 

The central cholinergic system has been implicated in the pathogenesis of affective disorder and in memory function, which is frequently found to be malfunctioning in depressed patients. The memory deficit elicited by chronic ECT in both patients and animals may be related to the decreased density and function of central muscarinic receptors, but it should be emphasized that the changes reported in cholinergic function are small and their relevance to the clinical situation remains to be established. 

More recent studies have not only challenged the early conclusion that the cholinergic system has no relation to attention, but these studies have brought into question the notion that the cholinergic system is not associated with short-term or immediate memory (Kopelman and Corn 1988 Rusted 1988 Rusted and Warburton 1988, 1989). Former studies had used only simple ( mechanic ) short-term retention tasks such as the digit-span for-... 

Drachman D, Leavitt J Human memory and the cholinergic system. Arch Neurol 30 113-121, 1974... 

Regarding the cholinergic system, there is evidence that the pathway from the substantia innominata to the cortex degenerates in Parkinsonism, and that the septohippocampal pathway is also functioning suboptimally. As more than 30% of Parkinsonian patients exhibit intellectual deterioration with deficits in cognitive function and memory, it is possible that these cholinergic deficits may account for at least some of the symptoms of parkinsonian dementia. 

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