Clinical trial NCT04277104: Does Acoustic Stimulation During Sleep Boost Slow Wave Sleep and Memory Performance?
Official title: Improving Slow Wave Sleep by Auditory Stimulation to Enhance Memory Consolidation and New Learning in Healthy Older Adults and Older Individuals at Risk for Dementia
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy
Mild Cognitive Impairment
Alzheimer Disease
Lead sponsor: University of Bern
Sponsor class: OTHER
First posted: 2020-02-20
Enrollment: 47
Sex: ALL
Minimum age (years): 60
Maximum age (years): 85
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: With aging the amount of slow wave sleep decreases drastically and this disruption is markedly exaggerated in older adults suffering from mild cognitive impairment and Alzheimer's disease. Critically, the disruption of slow wave sleep and cognitive decline seem bidirectionally linked forming a vicious cycle. In the long run, improving slow wave sleep might be a useful intervention tool to delay the onset of cognitive decline. The present study aims at improving slow wave sleep and memory functions through a closed-loop acoustic stimulation approach. A closed-loop algorithm is used that detects slow waves in the electroencephalogram and is programmed to present short tones (50 ms) in the rhythm of these waves. This procedure has shown to boost both slow wave sleep as well as memory performance, mainly in young adults and when applied for one night. Here, the investigators apply tones via multiple consecutive nights and assess memory performance during this 3-night intervention.


Eligibility criteria: Inclusion Criteria:

* Written informed consent
* Fluent in German
* Normal or corrected to normal vision
* Unimpaired hearing
* For healthy group: Montreal Cognitive Assessment Score ≥ 26
* For MCI group: Montreal Cognitive Assessment Score \< 26
* For at risk group: smoker, high cholesterol, high blood pressure and high fasting plasma glucose OR smoker, high BMI, physically inactive, unhealthy dietary habits

Exclusion Criteria:

* Known sleep problems such as Insomnia, restless leg syndrome, apnea
* Irregular sleep pattern
* Symptoms of depression
* History of untreated severe neurological and psychiatric diseases
* Alcohol or substance abuse
* Use of medication acting on the central nervous system

Primary outcomes:
measure: Change from baseline episodic memory performance after three nights of intervention
timeFrame: The change in memory performance will be assessed between the baseline measurement (evening before the first intervention night) and on the morning of the last intervention night (1 hour after waking), 3 days after initial encoding
measure: Change from baseline performance in computer-based verbal new learning task (episodic memory) after three nights of intervention
timeFrame: The change in new learning performance will be assessed between the baseline measurement (morning before the first intervention night) and on the morning of the last intervention night (1.5 hour after waking), 3 days after.
Secondary outcomes:
measure: Improvements in sleep physiology
timeFrame: Three consecutive nights of EEG measurement/polysomnography
measure: Improvement in episodic memory performance at follow-ups
timeFrame: One week as well as 3 months after intervention
measure: Improvement in new learning of episodic memory at follow-ups
timeFrame: One week as well as 3 months after intervention
measure: Decreases in plasma amyloid-beta
timeFrame: Blood samples will be taken twice: on the morning before the first intervention night, on the morning after the last intervention night (3 days apart)
Other outcomes:
measure: General cognitive functions: working memory
timeFrame: Assessed four times: on the morning before the first intervention night, on the morning after the last intervention night, one week after and 3 months after the intervention
measure: General cognitive functions: cognitive flexibility
timeFrame: Assessed four times: on the morning before the first intervention night, on the morning after the last intervention night, one week after and 3 months after the intervention
measure: General cognitive functions: cognitive inhibition
timeFrame: Assessed four times: on the morning before the first intervention night, on the morning after the last intervention night, one week after and 3 months after the intervention
Locations:
city: Bern
country: Switzerland
facility: University Hospital of Old Age Psychiatry and Psychotherapy
Study officials:
affiliation: University hospital of old age psychiatry and psychotherapy
name: Stefan Klöppel, Prof.
role: PRINCIPAL_INVESTIGATOR
References: