The article by Shiozaki et al 1 demonstrating significantly less muscarinic acetylcholine receptor binding sites in the temporal cortex in dementia with Lewy bodies than in Alzheimer's disease and different upregulation of the m1 and m2 receptor subtypes suggests differences in the manner of degeneration of the cholinergicsystem between both dementing disorders that may be of basic and practical therapeutic relevance. The more severe reduction of ChAT activity in the neocortex in dementia with Lewy bodies than in Alzheimer's disease, the higher upregulation of the postsynaptic m1 receptor in dementia with Lewy bodies, and the higher level of the presynaptic m 2 receptor subtype in Alzheimer's disease suggest a severe depletion of presynaptic projection neurons in dementia with Lewy bodies but their relative preservation or upregulation in Alzheimer's disease.1These data are …