Back to resultsEffects of Gamma-tACS on Memory and Sleep
Primary Purpose
Transcranial Alternating Current Stimulation, Aging, Cognitive Decline
Status
Recruiting
Phase
Not Applicable
Locations
United States
Study Type
Interventional
Intervention
Gamma transcranial alternating current stimulation
Control transcranial alternating current stimulation
EEG headband
Actigraphy wristband
Sponsored by
About this trial
This is an interventional other trial for Transcranial Alternating Current Stimulation
Eligibility Criteria
Inclusion Criteria: >50 years old Exclusion Criteria: 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 TMS (Transcranial Magnetic Stimulation) 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
Sites / Locations
- Carolina Center for NeurostimulationRecruiting
Arms of the Study
Arm 1
Arm 2
Arm Type
Experimental
Experimental
Arm Label
First gamma (40Hz) stimulation, then active control (21Hz) stimulation
First active control (21 Hz) stimulation, then gamma (40 Hz) stimulation
Arm Description
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.
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.
Outcomes
Primary Outcome Measures
Percent of Participants Tolerating Cognitive Testing During tACS
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
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
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
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
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
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
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.
Proportion of Participants in which it is Possible to Obtain at Least 4 Hours EEG Recording
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.
Proportion of Participants who Wear the EEG Device During all Three Nights for at Least 4 Hours
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
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.
Amount of Slow Wave Sleep in Sleep-EEG
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.
Secondary Outcome Measures
Performance in Phonematic Fluency
To investigate the effect of a single session of gamma-tACS (compared to control-tACS) on a phonematic fluency-task during 1 minute. Number of correct words, number of perseverations and number of rule breaks will be calculated.
Executive Functioning (Stroop Test)
To investigate the effect of a single session of gamma-tACS (compared to control-tACS) on the Stroop Color and Word Test during and on the day after the intervention. Time for test completion and errors will be calculated.
Executive Functioning (Trail Making Test)
To investigate the effect of a single session of gamma-tACS (compared to control-tACS) on the Trail Making Test (TMT) during and on the day after the intervention. Time for test completion and errors will be calculated.
Attentional Performance (TAP)
To investigate the effect of a single session of gamma-tACS (compared to control-tACS) on subtests of the Test of Attentional Performance (TAP) during and on the day after the intervention. Percentile ranks for the following subtests will be calculated: Alertness, Go/NoGo, Divided Attention, Visual Scanning.
Full Information
NCT ID
NCT05907707
First Posted
May 18, 2023
Last Updated
September 8, 2023
Sponsor
University of North Carolina, Chapel Hill
1. Study Identification
Unique Protocol Identification Number
NCT05907707
Brief Title
Effects of Gamma-tACS on Memory and Sleep
Official Title
Effects of Transcranial Alternating Current Stimulation (tACS) at Gamma Band Frequencies on Memory Recall and Sleep in Healthy Elderly Participants
Study Type
Interventional
2. Study Status
Record Verification Date
June 2023
Overall Recruitment Status
Recruiting
Study Start Date
June 28, 2023 (Actual)
Primary Completion Date
December 28, 2023 (Anticipated)
Study Completion Date
December 28, 2023 (Anticipated)
3. Sponsor/Collaborators
Responsible Party, by Official Title
Sponsor
Name of the Sponsor
University of North Carolina, Chapel Hill
4. Oversight
Studies a U.S. FDA-regulated Drug Product
No
Studies a U.S. FDA-regulated Device Product
Yes
Device Product Not Approved or Cleared by U.S. FDA
Yes
Product Manufactured in and Exported from the U.S.
No
5. Study Description
Brief Summary
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.
6. Conditions and Keywords
Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Transcranial Alternating Current Stimulation, Aging, Cognitive Decline, Memory, Sleep
7. Study Design
Primary Purpose
Other
Study Phase
Not Applicable
Interventional Study Model
Crossover Assignment
Masking
ParticipantCare ProviderInvestigatorOutcomes Assessor
Allocation
Randomized
Enrollment
50 (Anticipated)
8. Arms, Groups, and Interventions
Arm Title
First gamma (40Hz) stimulation, then active control (21Hz) stimulation
Arm Type
Experimental
Arm Description
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.
Arm Title
First active control (21 Hz) stimulation, then gamma (40 Hz) stimulation
Arm Type
Experimental
Arm Description
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.
Intervention Type
Device
Intervention Name(s)
Gamma transcranial alternating current stimulation
Other Intervention Name(s)
DC-STIMULATOR MC Stimulator Plus
Intervention Description
tACS (gamma frequency, 40Hz) during cognitive testing (about 40 minutes duration).
Intervention Type
Device
Intervention Name(s)
Control transcranial alternating current stimulation
Other Intervention Name(s)
DC-STIMULATOR MC Stimulator Plus
Intervention Description
tACS (control frequency, 21Hz) during cognitive testing (about 40 minutes duration).
Intervention Type
Device
Intervention Name(s)
EEG headband
Other Intervention Name(s)
ULTEEMNite
Intervention Description
At-home, ambulatory, single-channel EEG headband which records brain activity during sleep
Intervention Type
Device
Intervention Name(s)
Actigraphy wristband
Intervention Description
At-home, ambulatory, wrist-worn accelerometer which records levels of motor activity during the whole day
Primary Outcome Measure Information:
Title
Percent of Participants Tolerating Cognitive Testing During tACS
Description
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.
Time Frame
Baseline (Day 1)
Title
Verbal Memory at Day 1
Description
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.
Time Frame
Baseline (Day 1)
Title
Verbal Memory at Day 2
Description
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.
Time Frame
Follow-Up (Day 2)
Title
Verbal Memory at Day 5
Description
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.
Time Frame
Follow-Up (Day 5)
Title
Associative Verbal Memory at Day 1
Description
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.
Time Frame
Baseline (Day 1)
Title
Associative Verbal Memory at Day 2
Description
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.
Time Frame
Follow-Up (Day 2)
Title
Associative Verbal Memory at Day 5
Description
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.
Time Frame
Follow-Up (Day 5)
Title
Proportion of Participants in which it is Possible to Obtain at Least 4 Hours EEG Recording
Description
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.
Time Frame
Baseline (Day 1)
Title
Proportion of Participants who Wear the EEG Device During all Three Nights for at Least 4 Hours
Description
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.
Time Frame
Baseline (Day 1)
Title
Amount of Sleep Spindles in Sleep-EEG
Description
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.
Time Frame
Baseline (Day 1)
Title
Amount of Slow Wave Sleep in Sleep-EEG
Description
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.
Time Frame
Baseline (Day 1)
Secondary Outcome Measure Information:
Title
Performance in Phonematic Fluency
Description
To investigate the effect of a single session of gamma-tACS (compared to control-tACS) on a phonematic fluency-task during 1 minute. Number of correct words, number of perseverations and number of rule breaks will be calculated.
Time Frame
Baseline (Day 1), Follow-Up (Day 2)
Title
Executive Functioning (Stroop Test)
Description
To investigate the effect of a single session of gamma-tACS (compared to control-tACS) on the Stroop Color and Word Test during and on the day after the intervention. Time for test completion and errors will be calculated.
Time Frame
Baseline (Day 1), Follow-Up (Day 2)
Title
Executive Functioning (Trail Making Test)
Description
To investigate the effect of a single session of gamma-tACS (compared to control-tACS) on the Trail Making Test (TMT) during and on the day after the intervention. Time for test completion and errors will be calculated.
Time Frame
Baseline (Day 1), Follow-Up (Day 2)
Title
Attentional Performance (TAP)
Description
To investigate the effect of a single session of gamma-tACS (compared to control-tACS) on subtests of the Test of Attentional Performance (TAP) during and on the day after the intervention. Percentile ranks for the following subtests will be calculated: Alertness, Go/NoGo, Divided Attention, Visual Scanning.
Time Frame
Baseline (Day 1), Follow-Up (Day 2)
Other Pre-specified Outcome Measures:
Title
Exploration of a Relationship (Correlation) between the Amount of Sleep Spindles and Slow Wave Sleep with Recall
Description
A relationship is defined as a correlation (Pearson's) between memory recall performance (amount of words recalled) and sleep EEG features (especially spindles, slow waves), i.e., whether better memory recall is associated with more sleep spindles and more slow wave sleep in the night after stimulation.
Time Frame
Baseline (Day 1), Follow-Up (Day 2)
Title
Exploration of a Relationship (Correlation) of Sleep-Wake-Schedule changes and Type of Stimulation
Description
To see whether there is a correlation (Pearson's) between type of stimulation/wearing EEG and the motor activity pattern (measured by actigraphy wristband).
Time Frame
Baseline (Day 1), Follow-Up (Day 2)
10. Eligibility
Sex
All
Minimum Age & Unit of Time
50 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion Criteria:
>50 years old
Exclusion Criteria:
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 TMS (Transcranial Magnetic Stimulation)
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
Central Contact Person:
First Name & Middle Initial & Last Name or Official Title & Degree
Flavio Frohlich, PhD
Phone
919-966-4584
Email
flavio_frohlich@med.unc.edu
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Flavio Frohlich, PhD
Organizational Affiliation
University of North Carolina, Chapel Hill
Official's Role
Principal Investigator
Facility Information:
Facility Name
Carolina Center for Neurostimulation
City
Chapel Hill
State/Province
North Carolina
ZIP/Postal Code
27516
Country
United States
Individual Site Status
Recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Flavio Frohlich, PhD
Phone
919-966-4584
Email
flavio_frohlich@med.unc.edu
12. IPD Sharing Statement
Plan to Share IPD
No
Learn more about this trial
Effects of Gamma-tACS on Memory and Sleep
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