Noise exposure accelerates the risk of cognitive impairment and Alzheimer's disease: Adulthood, gestational, and prenatal mechanistic evidence from animal studies.

• Chronic noise exposure dysregulates the neuroendocrine system leading to hyperactivity of the hypothalamic-pituitary-adrenal (HPA)-axis. • Stress hormones adversely affect cell biology and neuronal circuitry leading to impairment in behavior. • Enduring dysregulation of the HPA-axis is the most mechanism associated with the harmful noise effects. • Noise stress shows a causative association with diverse landmarks of Alzheimer's disease (AD) with a hyper-susceptibility in females. • Functional and Neuroimaging studies are suggested to quantify the contribution of noise in predisposing AD in human. This review examines the adverse impacts of different noise exposure paradigms on the neuroendocrine system, hippocampal and neocortical structures, cognitive performances, and the development of Alzheimer's disease (AD)-like neuropathological changes in the brain of laboratory animals. Studies were reviewed in three periods during the lifespan including: adult animals exposed to noise, female rodents exposed to noise during gestation, and offspring exposed to noise during the prenatal period. Findings imply that chronic noise exposure dysregulates the neuroendocrine system leading to hyperactivation of the sympathetic divisions of the autonomic nervous system (i.e., the hypothalamic-pituitary-adrenal (HPA)-axis), and increases stress hormones that affect brain and behaviour. Enduring dysregulation of the HPA-axis was the most discussed mechanism for the harmful effect of noise during the lifespan. Studies also suggest a causative association of noise with diverse indicators of the AD-like neuropathology in rodents and a hypersusceptibility in females. The results indicate the importance of future neuroimaging studies to quantify the potential contribution of noise in predisposing cognitive decline and preclinical signs of dementia in humans. [ABSTRACT FROM AUTHOR]