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Completed

NCT Number: NCT04646499

Feasibility of Gamma Transcranial Alternating Current Stimulation to Reduce Beta-amyloid Load and Improve Memory

This project assessed the feasibility of transcranial alternating current stimulation in the gamma band to lower beta-amyloid load and improve memory performance.

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Key information

Conditions

Mild Cognitive Impairment Cognition Disorders Cognitive Dysfunction Mental Disorders Neurocognitive Disorders

Age range

55 year–80 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

University of California, San Francisco

San Francisco, California, 94158, United States

About this study

Thirteen individuals with aMCI received eight 60-minute sessions of 40-Hz (gamma) transcranial alternating current stimulation (tACS) in a single-arm design. Outcome measures were assessed pre- and post-intervention.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • English speaking
  • Grade 12 or more education
  • Normal or corrected to normal vision and hearing
  • Ability to complete cognitive tasks
  • Ability to cooperate and comply with all study procedures
  • Ability to tolerate tACS
  • Self-reported memory complaint
  • Diagnosed with mild cognitive impairment
  • Amyloid positive

Exclusion criteria

  • Neurological or psychiatric disorders other than mild cognitive impairment
  • Receiving investigational medications or have participated in a trial with investigational medications within last 30 days
  • Family history of epilepsy
  • Implanted electronic devices (e.g., pacemaker)
  • Prior head trauma
  • Pregnant
  • IQ < 80
  • Taking cholinesterase inhibitory, memantine, or psychotropic medication
  • Taking anti-depressants or anti-anxiety medication
  • Color blind
  • Substance abuse
  • Glaucoma
  • Macular degeneration
  • Amblyopia (lazy eye)
  • Strabismus (crossed eyes)

Treatment and study plan

Transcranial Alternating Current Stimulation

Device

Transcranial alternating current stimulation (tACS) will be applied at 40 Hz (gamma band) during eight sessions over the course of a month.

Primary outcomes

  1. Side Effects

    Time frame: Average of all post-tACS sessions, up to 1 month

    Side effects were measured on a scale from 0 (not noticable) to 10 (not tolerable): headache, neck pain, scalp pain, tingling, itching, burning sensation, increased sleepiness, trouble concentrating, acute mood change, and phosphenes. Average rating across all measures reported as indicator of side effects.

  2. Drop Out

    Time frame: post-tACS, up to 1 month

    Drop out rate will be assessed as the number of participants who withdraw or are withdrawn from the study.

Secondary outcomes

  1. Beta Amyloid Load Change

    Time frame: pre-tACS (baseline) and post-tACS (1 month)

    Change in plasma-based beta amyloid (AB) load was assessed as the AB42/40 ratio, calculated as post minus pre AB42/40 ratio. Greater increase is better.

  2. Memory: Recall Change

    Time frame: pre-tACS (baseline), post-tACS (after one month of treatment)

    Episodic memory was assessed pre and post intervention as the number of words correct during the short delay free recall portion of the California Verbal Learning Test. Change was assessed as post minus pre. Greater increase is better.

  3. Memory: Paired Associates Change

    Time frame: pre-tACS (baseline), post-tACS (after one month of treatment)

    Episodic memory was assessed pre and post intervention from memory accuracy for a paired associates task for visual objects. Change was assessed post minus pre. Greater increase is better.

  4. Memory: Fluency Change

    Time frame: pre-tACS (baseline), post-tACS (after one month of treatment)

    Episodic memory fluency was assessed pre and post intervention from performance on the FAS task. Unit of measurement is the number of words names starting with the letter f, a, or s. Change was calculated as post minus pre. Greater increase is better.

  5. Change in Tau

    Time frame: pre-tACS (baseline), post-tACS (after one month of treatment)

    Plasma tau levels was assessed pre and post intervention. Change was calculated as post minus pre. Greater decrease is better.

Sponsors and collaborators

Lead sponsor

University of California, San Francisco

Other

Collaborators

  • National Institute on Aging (NIA)

Registry information

Important dates

Study start
2021
Primary completion
2021
Study completion
2022
First posted
Nov 30, 2020
Registry last updated
Jul 27, 2023

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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