Effects of Transcranial Alternating Current Stimulation (tACS) at Gamma Band Frequencies on Memory Recall and Sleep in Healthy Elderly Participants
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 11
- 试验地点
- 2
- 主要终点
- Percent of Participants Tolerating Cognitive Testing During tACS
研究概览
简要总结
The purpose of this clinical trial is to investigate the feasibility and efficacy of non-invasive transcranial alternating current stimulation (tACS) at gamma frequency in enhancing memory recall and modulating sleep network dynamics measured by at-home electroencephalography (EEG) in healthy elderly people. Eligible participants will first collect sleep EEG at home for one night to acclimate to the data collection during sleep. Participants are then randomized into first undergoing either tACS at gamma band frequencies (i.e. 40Hz) or tACS at a control frequency (i.e. 21Hz). Stimulation is administered in the lab during a cognitive testing battery that includes memorizing items. After a night of sleep with EEG at home, participants return to the lab the following day to measure memory recall. Recall is performed again after five days. This sequence of encoding during stimulation in the lab, sleep EEG at home for one night, and recall is then repeated for the other stimulation condition about a week later. Participants are wearing an actigraphy wristband throughout the study period.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Other
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 50 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •>50 years old
排除标准
- •Implanted device or metal in head (including cochlear implant or other hearing aid), cardiac pacemaker or any other powered medical device
- •Known neurological disease from history (epilepsy, sleep disorder (insomnia, sleep apnea, restless legs syndrome, parasomnia), stroke or transitory ischemic attack, cognitive impairment, neurodegenerative disease (for example Alzheimer's disease, Parkinson's disease or amyotrophic lateral sclerosis), immune-mediated disease of the central nervous system, chronic infectious brain disease, brain tumor, traumatic brain injury with loss of consciousness and/or intracranial bleeding, chronic pain with the need for daily analgesic use)
- •Positive screening for epilepsy (questionnaire)
- •Pathological Montreal Cognitive Assessment (MoCA <26/30 points)
- •Brain surgery in the past (lifetime)
- •Known psychiatric disorder from history (schizophrenia (lifetime), obsessive compulsive disorder (OCD; lifetime), borderline personality disorder (lifetime), anxiety disorder (lifetime), bipolar disorder (lifetime), psychosis (lifetime), eating disorder (lifetime), depression (within the last three months)
- •Positive screening for anxiety disorder (GAD-7 ≥10/21 points) or positive screening for depression (PHQ-9 ≥5/27 points)
- •Known other relevant medical condition from history (moderate to severe chronic obstructive pulmonary disease (COPD), abnormal kidney function (defined as estimated Glomerular Filtration Rate <60ml/min), current liver disease (defined as hepatitis and/or liver cirrhosis), cancer, diabetes mellitus, cardiac disease (heart failure, myocardial infarct, atrial fibrillation and revascularization - all within the last three months)
- •Working in night shifts or going to bed after midnight on 3 or more nights per week
- •Positive screening for sleep disorder (PSQI >5/21 points)
- •Psychotropic treatment or illegal drugs (including cannabis) within the last three months
- •Indication for alcohol use disorder: AUDIT score (Alcohol Use Disorders Identification Test; screening for unhealthy alcohol use) ≥7 for females and for males ≥ 65 years or ≥8 for males <65 years
- •Not willing to abstain alcohol at least 24 hours before each study visit
- •Pregnancy, planned pregnancy, fertility treatment planned or ongoing
- •Having experienced an adverse event in the past after receiving Transcranial Magnetic Stimulation (TMS)
- •If, after filling out a questionnaire on the participant's medical history that informs researchers of relevant events that marginally increase the risk of an adverse event occurring during TMS, researchers will exercise their expert judgement to determine whether that participant should be excluded
研究组 & 干预措施
First gamma (40Hz) stimulation, then active control (21Hz) stimulation
After collecting sleep EEG at home for one night to acclimate to the data collection during sleep, participants first receive gamma (40Hz) tACS on Day 1 followed by a 5-9 day washout. Participants then receive active control (21Hz) stimulation.
干预措施: Gamma transcranial alternating current stimulation (Device)
First active control (21 Hz) stimulation, then gamma (40 Hz) stimulation
After collecting sleep EEG at home for one night to acclimate to the data collection during sleep, participants first receive active control (21Hz) tACS on Day 1 followed by a 5-9 day washout. Participants then receive gamma (40Hz) stimulation.
干预措施: Gamma transcranial alternating current stimulation (Device)
First active control (21 Hz) stimulation, then gamma (40 Hz) stimulation
After collecting sleep EEG at home for one night to acclimate to the data collection during sleep, participants first receive active control (21Hz) tACS on Day 1 followed by a 5-9 day washout. Participants then receive gamma (40Hz) stimulation.
干预措施: Control transcranial alternating current stimulation (Device)
First gamma (40Hz) stimulation, then active control (21Hz) stimulation
After collecting sleep EEG at home for one night to acclimate to the data collection during sleep, participants first receive gamma (40Hz) tACS on Day 1 followed by a 5-9 day washout. Participants then receive active control (21Hz) stimulation.
干预措施: EEG headband (Device)
First gamma (40Hz) stimulation, then active control (21Hz) stimulation
After collecting sleep EEG at home for one night to acclimate to the data collection during sleep, participants first receive gamma (40Hz) tACS on Day 1 followed by a 5-9 day washout. Participants then receive active control (21Hz) stimulation.
干预措施: Control transcranial alternating current stimulation (Device)
First gamma (40Hz) stimulation, then active control (21Hz) stimulation
After collecting sleep EEG at home for one night to acclimate to the data collection during sleep, participants first receive gamma (40Hz) tACS on Day 1 followed by a 5-9 day washout. Participants then receive active control (21Hz) stimulation.
干预措施: Actigraphy wristband (Device)
First active control (21 Hz) stimulation, then gamma (40 Hz) stimulation
After collecting sleep EEG at home for one night to acclimate to the data collection during sleep, participants first receive active control (21Hz) tACS on Day 1 followed by a 5-9 day washout. Participants then receive gamma (40Hz) stimulation.
干预措施: EEG headband (Device)
First active control (21 Hz) stimulation, then gamma (40 Hz) stimulation
After collecting sleep EEG at home for one night to acclimate to the data collection during sleep, participants first receive active control (21Hz) tACS on Day 1 followed by a 5-9 day washout. Participants then receive gamma (40Hz) stimulation.
干预措施: Actigraphy wristband (Device)
结局指标
主要结局
Percent of Participants Tolerating Cognitive Testing During tACS
时间窗: Baseline (Day 1)
To establish acceptability of tACS combined with cognitive testing in healthy elderly participants and will be considered acceptable if at least \>/= 80% of participants tolerate the procedure.
Verbal Memory at Day 1
时间窗: Baseline (Day 1)
Participants will memorize 15 words ("Rey Auditory Verbal Learning Test") during gamma-tACS or control-tACS. They will be required to recall the words on the same day. The number of correctly remembered words will be recorded.
Verbal Memory at Day 2
时间窗: Follow-Up (Day 2)
Participants will memorize 15 words ("Rey Auditory Verbal Learning Test") during gamma-tACS or control-tACS. They will be required to recall the words on the day after. The number of correctly remembered words will be recorded.
Verbal Memory at Day 5
时间窗: Follow-Up (Day 5)
Participants will memorize 15 words ("Rey Auditory Verbal Learning Test") during gamma-tACS or control-tACS. They will be required to recall the words after 5 days. The number of correctly remembered words will be recorded.
Associative Verbal Memory at Day 1
时间窗: Baseline (Day 1)
Participants will memorize 8 word-pairs during gamma-tACS or control-tACS. They will be required to recall the pairs on the same day. The number of correctly remembered word pairs will be recorded.
Associative Verbal Memory at Day 2
时间窗: Follow-Up (Day 2)
Participants will memorize 8 word-pairs during gamma-tACS or control-tACS. They will be required to recall the pairs on the day after. The number of correctly remembered word pairs will be recorded.
Associative Verbal Memory at Day 5
时间窗: Follow-Up (Day 5)
Participants will memorize 8 word-pairs during gamma-tACS or control-tACS. They will be required to recall the pairs after 5 days. The number of correctly remembered word pairs will be recorded.
Percentage of Participants in Which it is Possible to Obtain at Least 4 Hours EEG Recording
时间窗: Baseline (Day 1)
To establish feasibility of at-home use of a single-channel EEG device during sleep. This will be considered feasible if the device has been worn for at least 4 hours during the first night for \>/= 80% of participants.
Percentage of Participants Who Wear the EEG Device During All Three Nights for at Least 4 Hours
时间窗: Baseline (Day 1)
To establish acceptability of at-home use of the single-channel EEG device during multiple nights. Acceptability will be considered as given if the device has been worn for at least 4 hours during each of the three nights in \>/=80% of participants.
Amount of Sleep Spindles in Sleep-EEG
时间窗: Baseline (Day 1)
To investigate the effect of a single session of gamma-tACS (compared to control-tACS) on the number of sleep spindles occuring during the night after the intervention. Sleep spindles during the first two hours of sleep-EEG will be counted. A sleep spindle is defined as a train of sinusoidal waves with frequency 11-16 Hz and a duration of at least 0.5 seconds.
Amount of Slow Wave Sleep in Sleep-EEG
时间窗: Baseline (Day 1)
To investigate the effect of a single session of gamma-tACS (compared to control-tACS) on the amount of slow wave sleep (deep/delta sleep) occuring during the night after the intervention. The amount of slow wave sleep during the first two hours of sleep-EEG will be counted.
次要结局
- Performance in Phonematic Fluency-Correct Words(Baseline (Day 1), Follow-Up (Day 2))
- Performance in Phonematic Fluency-Perseverations(Baseline (Day 1), Follow-Up (Day 2))
- Performance in Phonematic Fluency-Rule Breaks(Baseline (Day 1), Follow-Up (Day 2))
- Executive Functioning (Time to Complete Stroop Test)(Baseline (Day 1), Follow-Up (Day 2))
- Executive Functioning (Trail Making Test)(Baseline (Day 1), Follow-Up (Day 2))
- Attentional Performance (TAP)(Baseline (Day 1), Follow-Up (Day 2))