The role of slow wave sleep in the development of dementia and its potential for preventative interventions

• Published in: Psychiatry research. Neuroimaging 2020-12, Vol.306, p.111178-111178, Article 111178
• Main Authors: Wunderlin, Marina, Züst, Marc Alain, Fehér, Kristoffer Daniel, Klöppel, Stefan, Nissen, Christoph
• Format: Article
• Language: English
• Subjects: Acoustic Stimulation; Aged; Aging; Alzheimer Disease - diagnosis; Amyloid beta-Peptides; Cognitive Dysfunction - diagnosis; Dementia; Humans; Memory; Memory - physiology; Sleep Initiation and Maintenance Disorders; Sleep, Slow-Wave - physiology; Slow wave sleep
• ISSN: 0925-4927; 1872-7506
• DOI: 10.1016/j.pscychresns.2020.111178

•Decreased sleep slow wave activity in old age is a biomarker of cognitive decline.•Slow wave activity and amyloid-beta are bidirectionally linked.•Acoustic stimulation during sleep can improve slow wave activity and memory.•Older adult's complex sleep physiology requires a fine-tuned stimulation algorithm.•Stimulation should be applied across multiple nights to maximize potential gains. The increasing incidence rate of dementia underlines the necessity to identify early biomarkers of imminent cognitive decline. Recent findings suggest that cognitive decline and the pathophysiology of Alzheimer's disease are closely linked to disruptions in slow wave sleep (SWS) – the deepest sleep stage. SWS is essential for memory functions and displays a potentially causal and bidirectional link to the accumulation of amyloid beta deposition. Accordingly, improving SWS in older adults – especially when at risk for dementia – might slow down the rate of cognitive decline. Recent work suggests that SWS can be improved by specifically targeting the electrophysiological peaks of the slow waves with acoustic stimulation. In older adults, this approach is still fairly new and accompanied by challenges posed by the specific complexity of their sleep physiology, like lower amplitude slow waves and fragmented sleep architecture. We suggest an approach that tackles these issues and attempts to re-instate a sleep physiology that resembles a younger, healthier brain. With enough SWS of high quality, metabolic clearance and memory functions could benefit and help slowing the process of cognitive aging. Ultimately, acoustic stimulation to enhance SWS could serve as a cost-effective, non-invasive tool to combat cognitive decline.