NCT01617408 · National Institute of Mental Health (NIMH)
Brain Stimulation and Vision Testing
What this study is about
Background: -The brain has two systems for recognizing objects. One system recognizes what an object is, and the other system recognizes where the object is located. However, there is much about how the brain handles and interprets the information from these two systems that is still unclear. Researchers want to study the parts of the brain that are involved in how vision is processed.
View original scientific description
Background: -The brain has two systems for recognizing objects. One system recognizes what an object is, and the other system recognizes where the object is located. However, there is much about how the brain handles and interprets the information from these two systems that is still unclear. Researchers want to study the parts of the brain that are involved in how vision is processed. They will use magnetic resonance imaging (MRI) and transcranial magnetic stimulation (TMS) or transcranial electrical stimulation (tES) on the brain. MRI measures what parts of the brain become more active when tasks are performed. TMS uses magnetic pulses to temporarily change the activity in parts of the brain. tES uses electrical current to temporarily change brain function. Objectives: -To better understand how people visually recognize different types of objects. Eligibility: -Healthy volunteers between 18 and 50 years of age, who only speak English. Design: * This study includes many different experiments on vision. Each experiment may combine visual tasks, MRI scans, and TMS or tES. Participants may be asked to have several different tests. Each test will require a separate visit to the National Institutes of Health. * Participants will be screened with a physical exam and medical history. They will have a baseline brain scan at the first visit. * Participants may do visual tasks alone, with MRI only, with TMS or tES only, or with MRI and TMS or tES combined. For the visual tasks, they will look at pictures of objects on a computer screen. Sometimes the images will appear very briefly (less than one-tenth of a second). Sometimes they will appear for up to 5 seconds. These images will be of things like faces, bodies, tools, and scenes. Participants will be asked to respond in different ways to the pictures. They may respond by typing on a computer keyboard or by pressing a button. Participants will have time to practice the tasks before the experiment. * Participants will remain on the study for up to 3 years.
Primary outcome measures
Online behavioral TMS experiments: performance accuracy, sensitivity (d') and reaction time (RT); Offline fMRI TBS experiments: task performance as well as reduced neuronal activity
Time frame: Ongoing
a. Behavioral TMS or tES experiments will measure the speed of a key press to indicate the correct answer and performance accuracy on the task. b. Offline TMS that combine TBS or tES with fMRI will measure changes in BOLD activation in the targeted region as well as in connected cortical areas identified with an independent localizer.
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
- Healthy Ages 18-50 years (inclusive) Able to read and write in English to guarantee understanding of all written and spoken instructions, which are in English
Exclusion criteria
- Individuals with conditions that could pose a risk relating to the safety of the MRI procedure, the TMS procedure or the combined TBS and fMRI procedure will be excluded from the protocol such as:
- Those with ferromagnetic metal in the cranial cavity or eye, e.g. aneurysm clip, implanted neural stimulator, cochlear implant, ocular foreign body.
- Those with an abnormality on a structural MRI.
- Those with an implanted cardiac pacemaker or auto-defibrillator
- Those with an insulin pump.
- Those with an irremovable body piercing
- Pregnant women
- Those with a visual impairment that will prevent them from performing the task
- Those without consent capacity will not be enrolled
- Those who do not understand the study instructions
- Those with a history of neurological problems. Neurological problems include, but are not limited to; family history of epilepsy, history of seizures and recurrent migraines.
- Those using medicines that can lower the seizure threshold. These can include but are not limited to; imipramine, amitriptyline, doxepine, nortriptyline, maprotiline, chlorpromazine, clozapine, foscarnet, ganciclovir, ritonavir, amphetamines.
- Those with a visual impairment that will prevent them from performing the task
- Those who have a significant psychiatric illness or have a history of psychiatric illness.
- NIMH staff/employees/family members
Where
- Bethesda, Maryland
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 8, 2026 · Source of record for eligibility and locations