Older Adults (50-90 Years)
Conditions
Keywords
aging, cognitive decline, brain stimulation, tSOS, tDCS, sleep, nap, daytime sleep, memory, memory consolidation
Brief summary
The beneficial effect of nocturnal as well as daytime sleep on memory consolidation is well-documented in young, healthy subjects. Slow wave sleep (SWS), in particular, with its slow oscillating activity have shown to enhance declarative, hippocampus-dependent memory representations. This impact of sleep on memory performance can be additionally enhanced by exogeneous induction of transcranial slow oscillating stimulation (tSOS) within the frequency range of SWS in humans (0,7- 0,8 Hz) during sleep, as has been demonstrated in young, healthy subjects. If older adults that commonly experiencing cognitive decline, including long-term retention of declarative memory - benefit from transcranial slow oscillatory stimulation (tSOS) during sleep in the same way has not been studied so far. The primary goal of the study is therefore to investigate the impact of oscillating current stimulation (tSOS) during a daytime nap on declarative memory consolidation in older adults.
Interventions
DEVICEbrain stimulation
DEVICESham Stimulation
Sponsors
Charite University, Berlin, Germany
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Investigator)
Eligibility
Sex/Gender
ALL
Age
50 Years to 90 Years
Healthy volunteers
Yes
Inclusion criteria
* age: 50-90 years * right handed * inobtrusive neuropsychological examination
Exclusion criteria
* untreated severe internal or psychiatric diseases * epilepsy * other severe neurological diseases eg., previous major stroke, brain tumour * dementia * contraindications to MRI
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Retention of declarative memories after 0.75 Hz stimulation during SWS, vs after sham stimulation during SWS | 4 weeks | Retention between stimulation conditions (0.75 Hz during SWS, vs sham stimulation during SWS) in the declarative memory task. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| 1. Amount of Slow wave Sleep | 4 weeks | 1\. Amount of slow wave sleep assessed by standard polysomnographic criteria in 0,75 Hz vs SHAM stimulation during SWS. |
| 2. sleep spindels | 4 weeks | 2.Spindel activity during sleep indicated via several spindel parameters like number, duration, frequency of spindles; compared between 0,75 Hz and SHAM stimulation during SWS. |
| 3. EEG-correlates | 4 weeks | 3\. Neuronal correlates (EEG-power in slow oscillation frequency bands induced by 0,75 Hz vs SHAM stimulation during SWS; EEG-correlates of encoding and retrieval of a declarative memory task). |
| 4. further memory systems | 4 weeks | 4\. Performance in further memory systems (procedural), compared between 0,75 Hz and SHAM stimulation during SWS. |
Countries
Germany
Outcome results
None listed