Effect of tACS Stimulation on Alpha Oscillations

Not Applicable

Completed

Brief Summary: 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.

Recruitment & Eligibility

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

Primary Outcome Measures

Name	Time	Method
Salivary Cortisol	Before and after 40 minutes of stimulation	Change before and after stimulation
Salivary Alpha Amylase	Before and after 40-minute stimulation at each session.	Change after stimulation

Secondary Outcome Measures

Name	Time	Method
Heart Rate Variability	Before and after 40-minute stimulation at each session.	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.
Percent Change in Respiration	Before and after 40-minute stimulation at each session.	Respiration rate, measured via a belt placed around the participant's abdomen as breaths per second.
Electroencephalogram (EEG)	Before and after 40-minute stimulation at each session.	The investigators will compare alpha oscillation power from resting-state EEG recordings before and after stimulation/sham at each session.

Locations (1): University of North Carolina Chapel Hill
🇺🇸
Chapel Hill, North Carolina, United States
University of North Carolina Chapel Hill
🇺🇸Chapel Hill, North Carolina, United States