title: Prepulse inhibition in patients with Alzheimer's disease.
abstract: Prepulse inhibition (PPI) is used as a measure for sensorimotor gating. Studies in animals have indicated that hippocampus and entorhinal cortex, structures which are affected in mild Alzheimer's disease (AD), are involved in the regulation of PPI. The objectives of this study were to determine if patients with very mild AD had altered PPI, and to study possible correlations between PPI and cognitive performance or neuropsychiatric symptoms. A passive acoustic PPI paradigm was applied in 48 patients with either mild AD or Mild Cognitive Impairment (MCI) and in 49 healthy controls. No differences were found between patients and healthy controls regarding PPI. Further, PPI was not found to correlate with cognitive performance or neuropsychiatric symptoms. PPI is significantly altered in patients with neuropsychiatric disorders associated with dopaminergic, glutamatergic and/or serotonergic dysfunctions, such as schizophrenia. Since mild AD is primarily associated with loss of cholinergic markers in the limbic regions this study suggests that acetylcholine only plays a minor role in the regulation of PPI.
authors.affiliation: Memory Disorders Research Unit, The Neuroscience Centre, Copenhagen University Hospital, Rigshospitalet, Copenhagen 2100, Denmark. hejl@inet.uni2.dk
authors.forename: Anne-Mette
authors.initials: AM
authors.lastname: Hejl
authors.forename: Birte
authors.initials: B
authors.lastname: Glenthøj
authors.forename: Torben
authors.initials: T
authors.lastname: Mackeprang
authors.forename: Ralf
authors.initials: R
authors.lastname: Hemmingsen
authors.forename: Gunhild
authors.initials: G
authors.lastname: Waldemar
mesh_terms: D000109:Acetylcholine / Q000378:metabolism; D000161:Acoustic Stimulation; D000368:Aged; D000544:Alzheimer Disease / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology; D001921:Brain / Q000378:metabolism / Q000503:physiopathology*; D003072:Cognition Disorders / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology; D018728:Entorhinal Cortex / Q000378:metabolism / Q000503:physiopathology; D005260:Female; D006185:Habituation, Psychophysiologic / Q000502:physiology; D006624:Hippocampus / Q000378:metabolism / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009433:Neural Inhibition / Q000502:physiology*; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests; D011930:Reaction Time / Q000502:physiology; D013216:Reflex, Startle / Q000502:physiology*
chemical_list: D000109:Acetylcholine