Sleep Stimulation to Enhance Waste Clearance in the Brain
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Closed-loop acoustic stimulation.
- Who it may be relevant to
- Registry conditions: Healthy, Subjective Cognitive Decline (SCD), Mild Cognitive Impairment (MCI), Alzheimer Disease (AD). Basic parameters: 18 years — 80 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Belgium
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
Unsure about the terms? Read our patient guide →
Official title
Enhancing Waste Clearance Through Sleep Stimulation
Overview
This study aims to examine whether multi-night closed-loop auditory stimulation (CLAS) during sleep can enhance waste clearance and memory consolidation in healthy adults and older adults with subjective cognitive decline or mild cognitive impairment who exhibit elevated brain amyloid levels identified through prior clinical screening. Specifically, the study investigates whether sleep stimulation increases the clearance of plasma biomarkers related to neurodegeneration, improves the brain's waste clearance system, and supports memory consolidation. Participants will undergo five nights each of CLAS and sham (no stimulation) interventions, with a washout period in between. They will also complete clinical assessments, including MRI scans, blood sample collection, and cognitive testing, and will keep track of subjective sleep quality, sleepiness, mood, and fatigue throughout the interventions.
Interventions
- Other Closed-loop acoustic stimulation
At-home sleep will be monitored using an EEG headband. Non-awakening auditory stimuli will be delivered during non-rapid eye movement sleep (NREM), timed to the ascending phase of slow waves, using either active or control (sham) conditions.
Primary outcome measures
- Plasma biomarkers [Time frame: Blood samples will be collected the morning after each intervention phase. Interventions are separated by one week.]
Secondary outcome measures (9)
- Glymphatic function [Time frame: MRI scans will be performed the morning after each intervention phase. Interventions are separated by one week.]
- CLAS evoked responses [Time frame: Each night of sleep during each intervention phase, whether receiving stimulation or sham.]
- Slow wave activity (SWA) [Time frame: Each night of sleep during each intervention phase, whether receiving stimulation or sham.]
- Sleep architecture [Time frame: Each night of sleep during each intervention phase, whether receiving stimulation or sham.]
- Change in memory performance [Time frame: Before and after each intervention period. Interventions are separated by one week.]
- Encoding capacity [Time frame: After each intervention phase. Interventions are separated by one week.]
- Alertness and sustained attention [Time frame: The PVT task will be assessed before and after each intervention phase. Interventions are separated by one week.]
- Subjective measures after sleep [Time frame: Each morning throughout the intervention phase.]
- Resting-state functional connectivity [Time frame: MRI scans will be performed the morning after each intervention phase. Interventions are separated by one week.]
Eligibility criteria
For the positive amyloid load group:
-Participants who meet the criteria of subjective cognitive decline or mild cognitive impairment (Clinical Dementia Rating < 2; Mini-Mental State Examination ≥ 21) and brain amyloid-beta (Aβ) accumulation confirmed by CSF or amyloid-PET, the inclusion age range is 55-80 years.
For healthy groups:
-Inclusion age range is 18-80 years.
Inclusion criteria
- Proficiency in the French language (close to native level) to complete the neuropsychological evaluation and cognitive tests.
- MRI compatibility: absence of metallic materials in the body (implants, vascular clips, certain types of orthopedic material, etc.), a pacemaker or other types of stimulators, cochlear implants, or any other electronic devices.
Exclusion criteria
- Current or past psychiatric or neurological conditions (except for those directly associated with the patient group).
- The presence of severe untreated sleep disorders.
- The presence of irregular sleep-wake cycles (due to shiftwork or extreme chronotype).
- The presence of moderate depression or high levels of anxiety.
- Ongoing treatment with psychotropic medications (benzodiazepines, antidepressants).
- Regular or excessive consumption of alcohol or caffeinated drinks.
- Consumption of other psychoactive substances known to have an impact on the central nervous system.
- Insufficient visual or auditory acuity to complete the assessments if uncorrected. Normal hearing is required for sound stimulation to be effective.
- Claustrophobia that prevents undergoing brain imaging (MRI).
- Pregnancy or currently breastfeeding
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Allocation
- Randomized
- Model
- Crossover
- Masking
- Single blind
- Primary purpose
- Basic science
Study locations
Belgium · 1 center
- Hôpital Universitaire de Bruxelles — Brussels
Identifiers
NCT: NCT07051239 · HUB2025028