NCT03407066 · National Eye Institute (NEI)
Perception, Sensation, Cognition and Action in Humans
What this study is about
Background: When people see and hear, the brain changes signals from the eyes and ears into perceptions and thoughts. No one fully understands how this happens. Researchers want to explore how healthy brains process sights and sounds. Objectives: To explore how people understand what they see and hear when the brain processes sights and sounds.
View original scientific description
Background: When people see and hear, the brain changes signals from the eyes and ears into perceptions and thoughts. No one fully understands how this happens. Researchers want to explore how healthy brains process sights and sounds. Objectives: To explore how people understand what they see and hear when the brain processes sights and sounds. Eligibility: Participants aged 13-65 who have at least 20/40 vision in at least one eye and do not use a hearing aid. Design: Some participants will take tests online anonymously. They will do computer tasks related to colors and behavior. In-person participants will be screened with medical history and physical exam. They will complete questionnaires and vision and hearing tests. Participants will plan how many testing sessions they will have and when. Sessions last 2-5 hours. They may include: * Magnetic Resonance Imaging: Magnets and radio waves to take pictures of the brain. Participants will lie on a table that slides in and out of a tube. They will do a task during the scan. * Magnetoencephalography: Records magnetic field changes from brain activity. Participants will sit or lie down. A cone will be lowered onto their head. They may do a task during the test. * Electromyography: Electrodes attached to the skin will measure the electrical activity of muscles. * Electroencephalogram: Electrodes on the scalp will record brain waves. * Electrocardiography: Electrodes on the chest will record heart electrical activity. * Tests of memory, attention, thinking, vision, and hearing. * Eye Tracking: Cameras will follow participants eye movements. They may wear a cap with infrared cameras in front of their eyes. During the sessions, participants vital signs may be monitored.
Primary outcome measures
MRI
Time frame: duration of the study
We will analyze the anatomical structures of the brain (structural MRI or DTI); amplitude of the BOLD signal (fMRI).
MEG
Time frame: duration of the study
We will quantify measures such as power spectrum, event- of task-related potentials, synchronization/de-synchronization and coherence between sensors or sources located close to the brain areas of interest.
Behavioral Measures
Time frame: duration of the study
We will quantify measures such as hit rate, reaction times, detection thresholds, eye movement patterns, color, shape and sound judgement. We may measure autonomic data during the course of the sub-study (such as heart rate, respiration, end-tidal CO2, skin conductance), which will be correlated to the outcome measures.
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
- is in good general health;
- is between 18 and 65 years old;
- has visual acuity of 20/40 in at least one eye (corrected with contact lenses is okay);
- has no hearing impairment requiring a hearing aid.
- is capable of understanding the procedures and requirements of this study;
- is willing and able to provide his/her own informed consent. Inclusion Criteria for On-line Participants A subject can be included in the on-line portion of the study if he/she:
- is in good general health;
- is between 18 and 65 years old;
- is capable of understanding the procedures and requirements of this study;
- is willing and able to provide his/her own informed consent. Inclusion Criteria for Genetic Screening/Off-site Participants A subject can be included in the off-site portion of the study if he/she:
- is between 13 and 65 years old;
- is in general good health;
- is capable of understanding the procedures and requirements of this study;
- is willing and able to provide his/her own informed consent.
Exclusion criteria
- Participant is pregnant
- Participant has serious vision or hearing problems; for some sub-studies focused on mechanisms of normal color vision, subjects who are colorblind will also be excluded;
- Participants without consent capacity will not be enrolled;
- Participant has a debilitating neurological disorder (examples include, but are not limited to: brain tumor, epilepsy, Alzheimer's Disease, Parkinson's Disease, multiple sclerosis) or a psychiatric disorder (examples include, but are not limited to: schizophrenia, clinical anxiety, severe depression, attention deficit hyperactivity disorder (ADHD), schizophrenia). Patients with non-debilitating conditions such as prosopagnosia, prosopometamorphosia (PMO), or aphantasia will have their conditions noted but will not be excluded);
- Participant has had a serious head injury or has a history of brain surgery. Head injury is defined as an injury to the brain from some external force resulting in loss of consciousness of 30 minutes or more;
- Participant has psychoactive drug or alcohol abuse or dependence in the past three months, as determined by the Drug Abuse Screening Test (DAST), except nicotine and caffeine. A score of 6 or greater on the DAST will be considered exclusionary. The effects of nicotine and caffeine in neuroimaging are attenuated if participants do not smoke or consume caffeine 2-3 hours before the scan session; Over-the-counter medication/herbals will not be a criterion for exclusion;
- Participant is an NEI employee within the Perception, Cognition and Action section. Additional Exclusion Criteria for MRI Sub-studies Contraindication to MR scanning include the following: metallic tattoos or metallic eyeliner; claustrophobia; inability to lie still on their back for approximately 2 hours; implanted cardiac pacemaker or auto-defibrillator; surgical aneurysm clips; implanted neural stimulator; artificial heart valves or pumps; metal fragments in cranial cavity, body or eyes (e.g., history as a metal worker); nitroglycerin patch (foil backer); cochlear implants (tubes are okay); weight \> 450 lbs; metal rods, plates, screws in body; shrapnel or bullet wound; intrauterine device (IUD) not approved on mrisafety.com (most IUDs are okay); vestibular or inner ear abnormality such as Meniere's disease; metallic braces; hair extensions attached with metallic wires; transdermal patches; movement disorders; dental implants; consumed of nicotine or caffeine in the two hours prior to the experimental session. Subjects may participate in this study but will not be allowed to have a 7.0 T MRI scan if they have metallic dental crowns or a bridge. Exclusion Criteria for Genetic Screening/Off-site Participants Off-site participation will be biased to participants with XY chromosomes until the genetic sequencing capability changes. We do not limit to just XY patients to provide the possibility of evaluating newer genetic sequencing capacity and because sequencing on XX can provide some information, even if it is not as decisive as on XY patients. Exclusion Criteria for On-line Participants Subjects may not participate in the on-line portion of the study if they:
- Do not have access to compatible equipment. For example, smartphone screens are too small to be used. The online platform will outline which devices may be used.
- Are unwilling to allow permission for JavaScript to run on the site and disable any script blockers.
- Are unwilling to agree to the on-line testing platform's terms and conditions.
Where
- Bethesda, Maryland
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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 Jun 5, 2026 · Source of record for eligibility and locations