Effects of PFC tDCS on Cognitive Control, Attention Lapses and Coordinated Neural Activity in the Theta and Alpha Bands

NCT04885322 | Recruiting FDA Device

• 1 other identifier: 1344169-8
• Study Type: interventional
• Target: 75
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to better understand the neural correlates of higher-order cognition, both in the healthy brain and in schizophrenia, and to determine how these mechanisms are modulated by transcranial direct current stimulation (tDCS) at frontal and occipital scalp sites. Testing the effects of tDCS at these scalp sites on cognitive task performance will help us understand the roles of the brain regions corresponding to these sites during higher-order cognitive processing (language comprehension, cognitive control, and related attention and memory processes). Behavioral and electrophysiological (EEG) measures will be used to assess cognitive performance. Our overarching hypothesis is that stimulating prefrontal circuits with tDCS can improve cognitive control performance, and ultimately performance on a range of cognitive tasks, as compared to stimulating a different cortical region (occipital cortex) or using sham stimulation. This study is solely intended as basic research in order to understand brain function in healthy individuals and individuals with schizophrenia. This study is not intended to diagnose, cure or treat schizophrenia or any other disease.

Conditions

Healthy

Outcome Measures

Primary Outcomes (9)

• Behavioral Cognitive Control Measures on the Stroop Task

  Incongruent versus Congruent difference in error rate and reaction time

  Through study completion, an average of 1 month

• EEG Cognitive Control Measures on the Stroop Task

  response-locked power in the theta frequency band (4-7 Hz)

  Through study completion, an average of 1 month

• Behavioral Attention Lapse Measures on the Stroop Task

  Error Rate on Incorrect Congruent trials (Full Lapses) and Slow-but-Correct Congruent trials (Partial Lapses)

  Through study completion, an average of 1 month

• EEG Attention Lapse Measures on the Stroop Task EEG Attention Lapse Measures on the Stroop Task

  Pre-trial power in the alpha frequency band (8-12 Hz)

  Through study completion, an average of 1 month

• Behavioral Cognitive Control Measures on the Change Detection Task Behavioral Cognitive Control Measures on the Change Detection Task

  WM storage capacity (k-max)

  Through study completion, an average of 1 month

• EEG Cognitive Control Measures on the Change Detection Task

  delay period power in the theta frequency band (4-7 Hz)

  Through study completion, an average of 1 month

• Behavioral Attention Lapse Measures on the Change Detection Task

  Attention factor (a); Guess factor (g)

  Through study completion, an average of 1 month

• EEG Attention Lapse Measures on the Change Detection Task

  Pre-trial power in the alpha frequency band (8-12 Hz)

  Through study completion, an average of 1 month

• Delivered tDCS Dose to PFC

  Estimated electric field in PFC region of interest

  Through study completion, an average of 1 month

Study Arms (3)

DLPFC Stimulation

EXPERIMENTAL

Intervention. 20 minutes of 2 mA direct current stimulation over the dorsolateral prefrontal cortex.

Device: Transcranial Direct Current Stimulation

Occipital Stimulation

EXPERIMENTAL

Intervention. 20 minutes of 2 mA direct current stimulation over the occipital cortex.

Device: Transcranial Direct Current Stimulation

Sham Stimulation

SHAM COMPARATOR

Placebo Comparator. 0.5-1 minutes of 2 mA direct current stimulation over the dorsolateral prefrontal cortex followed by 19-19.5 minutes of sham stimulation

Device: Transcranial Direct Current Stimulation

Interventions

Transcranial Direct Current Stimulation DEVICE

In tDCS, saline-soaked electrodes are temporary affixed to the scalp and connected to a battery-powered current generator. A weak (2 mA) constant current is then briefly applied (\~20 minutes) to stimulate the targeted brain area. The targeted brain area is determined by the Study Arm.

DLPFC Stimulation; Occipital Stimulation; Sham Stimulation

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• between ages of 18 and 50
• ability to sufficiently speak and understand English so as to be able to understand and complete cognitive tasks
• ability to give valid informed consent

You may not qualify if:

• no history of head trauma
• no current or previous history of treatment with psychotropic medication
• corrected vision 20/30 or better
• tDCS/MRI contraindications, including: pregnancy, ferrous metal in any part of the body, serious medical conditions, claustrophobia, metallic implants, skin damage, conditions such as eczema at electrode sites, cranial pathologies

Sponsors & Collaborators

• University of California, Davis: lead

Study Sites (1)

Imaging Research Center

Sacramento, California, 95817, United States

RECRUITING

MeSH Terms

Interventions

Transcranial Direct Current Stimulation

Intervention Hierarchy (Ancestors)

Electric Stimulation Therapy; Therapeutics; Convulsive Therapy; Psychiatric Somatic Therapies; Behavioral Disciplines and Activities; Electroshock; Psychological Techniques

Central Study Contacts

Minhtrang Chu

CONTACT

1-916-734-1482; mihchu@ucdavis.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 4, 2021
• First Posted: May 13, 2021
• Study Start: April 14, 2021
• Primary Completion (Estimated): June 30, 2027
• Study Completion (Estimated): June 30, 2027
• Last Updated: December 5, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)