Concomitant serotonergic and cholinergic deficits have been observed inthe frontal and temporal cortices in AD patients as compared to healthycontrols, and the ratio of serotonin to acetylcholinesterase in the temporalcortex is correlated with psychosis in female patients.105 Cholinesterase inhibitorsused in the treatment of AD may improve hallucinations and delusions in somepatients.106. This evidence concerns the gene ACHE and Alzheimer disease.