Acoustic stimulation during sleep predicts long-lasting increases in memory performance and beneficial amyloid response in older adults

• Published in: Age and ageing 2023-12, Vol.52 (12)
• Main Authors: Wunderlin, Marina, Zeller, Céline Jacqueline, Senti, Samira Rafaela, Fehér, Kristoffer Daniel, Suppiger, Debora, Wyss, Patric, Koenig, Thomas, Teunissen, Charlotte Elisabeth, Nissen, Christoph, Klöppel, Stefan, Züst, Marc Alain
• Format: Article
• Language: English
• Subjects: Acoustic Stimulation - methods; Aged; Cognition - physiology; Electroencephalography - methods; Humans; Memory Consolidation - physiology; Research Paper; Sleep
• ISSN: 0002-0729; 1468-2834; 1468-2834
• DOI: 10.1093/ageing/afad228

Abstract Background Sleep and neurodegeneration are assumed to be locked in a bi-directional vicious cycle. Improving sleep could break this cycle and help to prevent neurodegeneration. We tested multi-night phase-locked acoustic stimulation (PLAS) during slow wave sleep (SWS) as a non-invasive method to improve SWS, memory performance and plasma amyloid levels. Methods 32 healthy older adults (agemean: 68.9) completed a between-subject sham-controlled three-night intervention, preceded by a sham-PLAS baseline night. Results PLAS induced increases in sleep-associated spectral-power bands as well as a 24% increase in slow wave-coupled spindles, known to support memory consolidation. There was no significant group-difference in memory performance or amyloid-beta between the intervention and control group. However, the magnitude of PLAS-induced physiological responses were associated with memory performance up to 3 months post intervention and beneficial changes in plasma amyloid. Results were exclusive to the intervention group. Discussion Multi-night PLAS is associated with long-lasting benefits in memory and metabolite clearance in older adults, rendering PLAS a promising tool to build upon and develop long-term protocols for the prevention of cognitive decline.