NCT00739362 · National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Effects of Brain Stimulation on Food Intake and Behavioral Weight Loss Treatment
What this study is about
This study will determine whether electrical stimulation of an area of the brain called the dorsolateral prefrontal cortex, which is important in determining the feeling of fullness after eating, affects how much food a person eats and weight loss over 4 weeks. It will also compare weight changes in people who attend weight loss counseling sessions and those who do not over this period of time.
View original scientific description
This study will determine whether electrical stimulation of an area of the brain called the dorsolateral prefrontal cortex, which is important in determining the feeling of fullness after eating, affects how much food a person eats and weight loss over 4 weeks. It will also compare weight changes in people who attend weight loss counseling sessions and those who do not over this period of time. Obese, non-diabetic people between 18 and 60 years of age who are in good health and who live in the Phoenix, AZ, metropolitan area are eligible for this study. Candidates must have a body mass index of 35 kg/m(2) or more and weigh less than 350 pounds. Participants are admitted to the NIH inpatient unit in Phoenix for the first 9 days of the study for tests, which include meal tests to determine eating behaviors and caloric intake, blood and urine tests, glucose tolerance test, weight measurement, psychological assessments and DEXA scan to measure body fat. For 3 of the days, they will be asked to eat all of their food from automated vending machines. Some subjects receive transcranial direct current stimulation (TDCS). For this procedure, electrodes that conduct electricity are placed on the head and arm and the current is turned on for 40 minutes. Some tingling may be felt under the electrodes. Other subjects receive sham TDCS, with the current turned on only very briefly. After the evaluations, subjects are discharged home from the NIH unit and instructed to eat 25 percent fewer calories than they consumed while on a weight maintenance diet the first 3 days of their inpatient stay. They maintain the lower calorie diet at home for 4 weeks. During this period they come to the NIH unit 3 days a week to receive either real or sham TDCS. ...
Interventions
DEVICE
Transcranial Direct Current Stimulation (TDCS)
Active tDCS (anodal left DLPFC)
OTHER
Sham/no-stimulation
Sham tDCS
Primary outcome measures
weight loss
Time frame: Baseline, week 9
Weight (kg)
food intake
Time frame: Baseline, week 9
Total energy intake during snack food taste test
brain fMRI activation in the left DLPFC when shown food vs. nonfood visual cues
Time frame: Weeks 1 and 9
Percent signal change in the left DLPFC when shown food vs. nonfood visual cues
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- BMI \>= 25 kg/m\^2
- Age 18-60 years. Women who are post-menopausal will be excluded from the study due to changes in their metabolism that could affect weight loss. We will set the cutoff at age 60 so that the age difference between the men and women is not too great for analysis purposes. Minors under the age of 18 will be excluded because the time requirements of the study are such that they would interfere with school schedules.
- Right-handedness (because the treatment will be given to the left dorsolateral prefrontal cortex and the evidence accumulated in this region was only in right-handed individuals).
- Weight stable (+/- 5 percent) for last 3 months as determined by volunteer report.
Exclusion criteria
- Weight \> 300 lbs (136 kg), as this is the general size limit of the fMRI machine. Participants \>300 pounds may be included if their body habitus will allow them to fit within the diameter of the MRI machine. This will be determined on a case-by-case basis after consultation with staff at Banner Health Neuroimaging Center.
- Use of medication affecting metabolism and appetite in the last three months
- Current pregnancy, pregnancy within the past 6 months or currently lactating
- History or clinical manifestations of acute or chronic disorders or conditions that may affect appetite or energy expenditure (such as, but not limited to type 1 or type 2 diabetes, Cushing s disease, thyroid disorders, coccidiomycoses)
- Gastrointestinal disease, including inflammatory bowel diseases (e.g. Chron s disease and ulcerative colitis), malabsorption syndromes (e.g. celiac disease), gastric ulcer (active) which may alter metabolism
- Current, unstable medical conditions such as hepatitis, renal insufficiency, cancer requiring treatment in the last 5 years, or central nervous system disorders etc. as assessed by history and physical exam
- Evidence of alcohol abuse as defined by \>= 8 point score on the Alcohol consumption screening AUDIT questionnaire in adults
- Evidence of drug use such as amphetamines, cocaine, heroin, or marijuana
- Current use of tobacco products that exceed "Very Low Dependence" on the Fagerstr(SqrRoot)(Delta)m Test for Nicotine Dependence Tool (score greater than 2)
- Postmenopausal women or symptoms of perimenopause (e.g. hot flashes, onset of irregular periods following age 40, elevation of FSH \>20 IU following age 40 years)
- Any conditions contraindicated for MRI (e.g., pacemaker, metal in the cranial cavity, significant claustrophobia, holes in the skull made by trauma or surgery)
- Any condition not specifically mentioned above that, in the opinion of the investigator, may interfere with the study or prove unsafe for participation.
Where
- Phoenix, Arizona
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jul 15, 2026 · Source of record for eligibility and locations