Modulation of Spontaneous Cortical Activity by tDCS: BRAIN Initiative I

The Impact of Spontaneous Cortical Activity on Neural Oscillations and Behavioral Performance: Evidence From High-definition tDCS and MEG

This study will determine whether transcranial direct current stimulation (tDCS) can be used alter the amplitude of spontaneous neural activity, and thereby modulate cognitive function in healthy adults

Study Overview

• Status: Completed
• Conditions: Brain Function
• Intervention / Treatment: Device: transcranial direct-current stimulation (tDCS)

Detailed Description

An emerging neurological tool, called transcranial Direct Current Stimulation (tDCS), has recently been shown to safely and effectively enhance cognition in healthy individuals, as well as reduce key symptomatology in disorders such as stroke and depression, with only negligible side effects. tDCS delivers low-amplitude current to the scalp using small electrodes and part of this current passes through the skull and modulates neural activity in the underlying brain region. How this tiny amount of electric current acts to improve cognitive function and reduce symptoms (e.g., motor impairments in stroke patients with a lesion in motor brain areas) is currently unknown, although many investigators across the world are now working on this problem. Magnetoencephalography (MEG) offers a unique view of neural function, as it can delineate changes in active brain regions with excellent temporal resolution (< 1 ms) and high spatial accuracy (2-3 mm). MEG non-invasively measures the magnetic fields that emanate from active neocortical cells. The potential of the MEG technique to precisely monitor the neural effects of tDCS shows extreme promise, but to date the method has been rarely utilized in this area.

Under this protocol, Modulation of Spontaneous Cortical Activity by tDCS: BRAIN Initiative I, approximately 124 participants will provide written informed consent, undergo cognitive and behavioral testing and a structural MRI during a single visit, and then return several weeks later (2-4 weeks) to complete a short tDCS session followed by a MEG recording (i.e., after tDCS). Most participants will return for two more visits, each separated by 2-4 weeks, that include a tDCS session followed by a MEG recording (i.e., 4 total visits). The three tDCS-MEG visits will be identical except that the nature of the stimulation (e.g., location, amplitude, direction/polarity) will be different.

• Study Type: Interventional
• Enrollment (Actual): 133
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Nebraska
    • Omaha, Nebraska, United States, 68198
      • University of Nebraska Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 19 years to 72 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Informed consent obtained from the participant.
• Age: 19-35 years of age at enrollment or 55-72 years of age at enrollment.
• Gender: males and females included.
• Right-handed based on the Edinburgh Handedness Inventory
• Cognitive functioning: Intelligent Quotient (IQ) of 85 - 115 on the Wechsler Adult Intelligence Scale-Revised
• Ability to complete the questionnaires in English, as not all the neuropsychological tests and questionnaires have been validated in other languages.

Exclusion Criteria:

• Current use of the following medications: psychotropic medications or other medications with significant CNS effects (e.g., antipsychotics, psychostimulants, anticonvulsants, alpha-agonists, adrenergic blockers, lithium, and sedating antihistamines), or other excluded medication.
• Current psychiatric diagnosis based on the Mini-International Neuropsychiatric Interview (MINI) and/or the adult attention-deficit/hyperactivity disorder (ADHD) diagnostic interview.
• Current substance abuse or substance dependence at any time.
• The presence of a known neurological disorder or any major medical illness or injury impacting neurological/psychiatric function (e.g., diabetes, epilepsy, cerebral palsy, traumatic brain injury, significant environmental/toxic injury, neurodegenerative disorder, past meningitis/encephalitis).
• General medical conditions: any major medical conditions that would interfere with involvement in the study or may affect central nervous system (CNS) function as judged by the investigative team.
• History of clinically-significant head trauma.
• Pregnancy
• Any other condition that, in the opinion of the investigator, is a contraindication to participation
• The presence of any ferrous metal implant, including orthodontics (e.g., braces), which may interfere with the MEG data acquisition and/or be a MRI safety concern.
• Inability to correct visual acuity to 20/20 with corrective lenses (we can correct from +5 to -6 diopters in .5 diopter steps, separately for each eye, with non-magnetic corrective lenses in the laboratory).

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Anodal Brain Stimulation; Participants will receive anodal stimulation using high-definition tDCS	Device: transcranial direct-current stimulation (tDCS); 20 minutes duration using high-definition system with center-surround configuration; Other Names: Transcranial electrical stimulation
Active Comparator: Cathodal Brain Stimulation; Participants will receive cathodal stimulation using high-definition tDCS	Device: transcranial direct-current stimulation (tDCS); 20 minutes duration using high-definition system with center-surround configuration; Other Names: Transcranial electrical stimulation
Sham Comparator: Sham Brain Stimulation (Placebo); Participants will receive sham stimulation (placebo) using high-definition tDCS	Device: transcranial direct-current stimulation (tDCS); 20 minutes duration using high-definition system with center-surround configuration; Other Names: Transcranial electrical stimulation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Behavioral Performance (Accuracy) on Cognitive Tests of Perceptual Processing	Do participants perform better in terms of accuracy following tDCS on behavioral measures of perceptual processing.	During the 90 minutes following stimulation
Behavioral Performance (Reaction Time) on Cognitive Tests of Perceptual Processing	Do participants perform better in terms of reaction time following tDCS on behavioral measures of perceptual processing.	During the 90 minutes following stimulation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The Power of Spontaneous Alpha Activity as Quantified by MEG Imaging	Does spontaneous alpha (9-13 Hz) power, as measured by MEG, get stronger following tDCS. Spontaneous activity refers to the level of background neural activity and is typically divided into frequency bands (e.g., alpha, gamma) that reflect the number of cycles per second. The outcome measure unit is nano-amperes square (nA^2) since source-resolved MEG measures reflect electric current strength and not voltage units as in electroencephalography (EEG). The square is necessary since we examined power, which is the square of amplitude in the frequency domain. The unit is also commonly expressed as nAm^2 since the strength of the electric current is over a defined length.	During the 90 minutes following stimulation
The Power of Oscillatory Alpha Activity as Quantified by MEG Imaging	Does oscillatory alpha neural activity, as measured by MEG, get stronger following tDCS. Oscillatory activity refers band-limited increases or decreases in the power of neural activity, relative to baseline, in response to a stimulus.	During the 90 minutes following stimulation
The Power of Spontaneous Gamma Activity as Quantified by MEG Imaging	Does spontaneous gamma (45-80 Hz) power, as measured by MEG, get stronger following tDCS. Spontaneous activity refers to the level of background neural activity and is typically divided into frequency bands (e.g., alpha, gamma) that reflect the number of cycles per second. The outcome measure unit is nano-amperes square (nA^2) since source-resolved MEG measures reflect electric current strength and not voltage units as in electroencephalography (EEG). The square is necessary since we examined power, which is the square of amplitude in the frequency domain. The unit is also commonly expressed as nAm^2 since the strength of the electric current is over a defined length.	During the 90 minutes following stimulation
The Power of Oscillatory Gamma Activity as Quantified by MEG Imaging	Does oscillatory gamma neural activity, as measured by MEG, get stronger following tDCS. Oscillatory activity refers band-limited increases or decreases in the power of neural activity, relative to baseline, in response to a stimulus.	During the 90 minutes following stimulation

Collaborators and Investigators

• Sponsor: University of Nebraska
• Collaborators: National Institute of Mental Health (NIMH)
• Investigators: Principal Investigator: Tony W Wilson, PhD, University of Nebraska

Study record dates

Study Major Dates

• Study Start (Actual): February 20, 2019
• Primary Completion (Actual): October 14, 2022
• Study Completion (Actual): May 31, 2023

Study Registration Dates

• First Submitted: August 15, 2018
• First Submitted That Met QC Criteria: September 12, 2018
• First Posted (Actual): September 14, 2018

Study Record Updates

• Last Update Posted (Actual): July 31, 2024
• Last Update Submitted That Met QC Criteria: July 7, 2024
• Last Verified: July 1, 2024

More Information

Terms related to this study

• Other Study ID Numbers: 0580-18-FB; RF1MH117032 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Upon completion of the study, de-identified data from this study will be stored in the National Institute of Mental Health's (NIMH) Data Archive.
• IPD Sharing Time Frame: Data will be fully updated by the end of the study and will remain publicly available indefinitely.
• IPD Sharing Access Criteria: Approval/Account from the NIMH
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

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