Effect of tACS Stimulation on Alpha Oscillations (AIMS1)

Rational Optimization of tACS for Targeting Thalamo-Cortical Oscillations (Experiment 2)

Transcranial Alternating Current Stimulation (tACS) is one method that has been demonstrated to enhance alpha oscillations in healthy participants by applying weak electrical currents to the scalp to modulate rhythmic brain activity patterns. This study will involve tACS-induced frontal alpha oscillations, EEG recordings, and other physiological and biological measures.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Device: XCSITE100 Stimulator tACS; Device: XCSITE100 Stimulator Sham

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • North Carolina
    • Chapel Hill, North Carolina, United States, 27514
      • University of North Carolina Chapel Hill

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Ages 18-65
• Capacity to understand all relevant risks and potential benefits of the study (informed consent)
• Negative pregnancy test for female participants

Exclusion Criteria:

• History of major neurological or psychiatric illness, including epilepsy
• Medication use associated with neurological or psychiatric illnesses
• Currently undergoing counseling or psychotherapy treatment for depression, anxiety, eating disorders, PTSD or other behavioral conditions
• First degree relative (parent, sibling, child) with major neurological or psychiatric illness
• Prior brain surgery
• Major head injury
• Any brain devices/implants (including cochlear implants and aneurysm clips)
• Braids or other hair styling that prevents direct access to the scalp (if removal not possible)
• Skin allergies or very sensitive skin
• Pregnant or nursing females
• Failure to pass a urinary drug test at the first session
• Use of hormonal birth control or supplements in the past two weeks
• Non English speakers
• Cardiovascular disease

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Sham Stimulation, then Alpha Stimulation; Participants receive sham stimulation at the first session, followed by a 5-9 day washout period and alpha stimulation at the second session. Sham Stimulation mimics the physical effects of stimulation, with up to one minute of stimulation during the session. Sham stimulation is delivered using the XCSITE100 Stimulator Sham. Participants will receive 2 mA of alternating current stimulation at a frequency of 10 Hz for 40 minutes. tACS stimulation is delivered using the XCSITE100 Stimulator tACS.	Device: XCSITE100 Stimulator tACS; Transcranial alternating current stimulation (tACS) is a method of noninvasive brain stimulation in which weak electrical current are applied to the scalp in a sine wave pattern to induce cortical oscillations at the frequency at which they are applied.; Other Names: tACS; Device: XCSITE100 Stimulator Sham; The participant will receive up to one minute of tACS stimulation until the stimulation fades. Sham stimulation mimics the skin sensations a participant would experience during a tACS session.; Other Names: Sham tACS
Experimental: Alpha Stimulation, then Sham Stimulation; Participants receive alpha stimulation at the first session, followed by a 5-9 day washout period and sham stimulation at the second session. Participants will receive 2 mA of alternating current stimulation at a frequency of 10 Hz for 40 minutes. tACS stimulation is delivered using the XCSITE100 Stimulator tACS. Sham Stimulation mimics the physical effects of stimulation, with up to one minute of stimulation during the session. Sham stimulation is delivered using the XCSITE100 Stimulator Sham.	Device: XCSITE100 Stimulator tACS; Transcranial alternating current stimulation (tACS) is a method of noninvasive brain stimulation in which weak electrical current are applied to the scalp in a sine wave pattern to induce cortical oscillations at the frequency at which they are applied.; Other Names: tACS; Device: XCSITE100 Stimulator Sham; The participant will receive up to one minute of tACS stimulation until the stimulation fades. Sham stimulation mimics the skin sensations a participant would experience during a tACS session.; Other Names: Sham tACS

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Salivary Alpha Amylase	Change after stimulation	Before and after 40-minute stimulation at each session.
Salivary Cortisol	Change before and after stimulation	Before and after 40 minutes of stimulation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Heart Rate Variability	Change in the ratio between the power in low frequency band and the power in high frequency band. As this outcome variable is a ratio between two items that are measured in microvolt^2, the ratio does not have a unit of measure.	Before and after 40-minute stimulation at each session.
Percent Change in Respiration	Respiration rate, measured via a belt placed around the participant's abdomen as breaths per second.	Before and after 40-minute stimulation at each session.
Electroencephalogram (EEG)	The investigators will compare alpha oscillation power from resting-state EEG recordings before and after stimulation/sham at each session.	Before and after 40-minute stimulation at each session.

Collaborators and Investigators

• Sponsor: University of North Carolina, Chapel Hill
• Collaborators: National Institute of Mental Health (NIMH); National Institutes of Health (NIH)

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2017
• Primary Completion (Actual): November 4, 2017
• Study Completion (Actual): November 4, 2017

Study Registration Dates

• First Submitted: June 2, 2017
• First Submitted That Met QC Criteria: June 2, 2017
• First Posted (Actual): June 6, 2017

Study Record Updates

• Last Update Posted (Actual): February 26, 2019
• Last Update Submitted That Met QC Criteria: February 7, 2019
• Last Verified: February 1, 2018

More Information

Terms related to this study

• Other Study ID Numbers: 16-1911a; R01MH111889-01 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: IPD will not be shared with other researchers.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No