Effects of Real vs. Soundless Acoustic Stimulation During Deep Sleep on Brain Activity, Memory, and Blood Biomarkers in Older Adults (60-85) With Mild Memory Impairment

University of Bern

Status: Enrolling

Conditions: Mild Cognitive Impairment (MCI); Alzheimer Disease; Cognitive Decline; Cognitive Impairment, Mild; Subjective Cognitive Decline (SCD)

Treatments: Other: Sham Phase-Locked Auditory Stimulation; Other: Phase-locked auditory stimulation (PLAS)

Study type: Interventional

Funder types: Other

Identifiers

NCT06669546

2024-00409

215333 (Other Grant/Funding Number)

Details and patient eligibility

About

This study aims to explore a non-invasive way to improve memory and slow cognitive decline in older adults by enhancing sleep quality. Dementia, a leading cause of death worldwide, is often associated with disturbed sleep, particularly the loss of deep, slow-wave sleep (SWS). SWS is important for memory and clearing waste from the brain. Poor SWS can worsen memory loss and allow harmful waste to build up, which may increase the risk of dementia.

The investigators are testing whether phase-locked auditory stimulation (PLAS) can improve SWS in people at a mild stage of cognitive impairment. PLAS uses short sounds played at specific moments to strengthen slow-wave brain activity during sleep. The investigators previous laboratory based research has shown that this can improve memory and help with clearing waste from the brain. Now, the investigators want to test this in a real-world setting, over a longer period, which is unfeasible in a laboratory setting.

In this study, 60 older adults will use home-use devices that deliver either real or sham (soundless) PLAS across two different 4-week periods. Memory will be tested using engaging "serious games." Before and after each experimental period, blood samples will be taken to measure dementia-related markers, and cognitive batteries will be performed. The investigators expect that PLAS will improve sleep, and that this will have a downstream effect on memory and brain clearance, potentially slowing the process of cognitive decline.

If successful, this could lead to the development of an affordable treatment that helps people maintain brain health and prevent dementia.

Enrollment: 60 estimated patients

Sex: All

Ages: 60 to 85 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Written informed consent
• Age between 60 and 85 years
• Cognitive impairment (subjective and/or MoCA between 23-26)
• Native German speakers or comparably fluent
• Normal or corrected-to-normal vision.
• Intact hearing
• A close cohabitant (partner/sibling) should be present to support participants in using study materials/devices.

Exclusion criteria

• Insomnia assessed by the Regensburg Insomnia Scale (RIS; Crönlein et al., 2013)
• Restless leg syndrome assessed by questions concerning typical symptoms.
• Sleep apnoea assessed by the Berlin Questionnaire (BQ; Netzer et al., 1999)
• Severely irregular sleep patterns assessed by the RIS and the Pittsburgh sleep quality index (PSQI; Buysse et al., 1989)
• Symptoms of depression (Geriatric Depression Scale (GDS; Yesavage et al., 1982) ≥ 5)
• History of untreated severe neurological and psychiatric diseases
• Alcohol or substance abuse
• Use of medication acting on the central nervous system

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Single Blind

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60 participants in 2 patient groups

PLAS first, sham second

Experimental group

Description:

In this study arm, participants will undergo a 4-week intervention period with real phase-locked auditory stimulation (PLAS) administered on nights from Monday to Friday. Following this initial intervention period, participants will have a 2-week washout phase. Finally, participants will enter the second intervention period, during which sham (soundless) PLAS will be administered.

Treatment:

Other: Phase-locked auditory stimulation (PLAS)

Other: Sham Phase-Locked Auditory Stimulation

Sham first, PLAS second

Experimental group

Description:

In this study arm, participants will undergo a 4-week intervention period with sham (soundless) phase-locked auditory stimulation (PLAS) administered on nights from Monday to Friday. Following this initial intervention period, participants will have a 2-week washout phase. Finally, participants will enter the second intervention period, during which real PLAS will be administered.

Treatment:

Other: Phase-locked auditory stimulation (PLAS)

Other: Sham Phase-Locked Auditory Stimulation