NIH Clinical Center Search the Studies: Study Number, Study Title

Protocol Details

Measuring the Latency Connectome in the Central Nervous System Using Neuroimaging and Neurophysiological Techniques

This study is currently recruiting participants.

Summary | Eligibility | Citations | Contacts




Sponsoring Institute

National Institute of Neurological Disorders and Stroke (NINDS)

Recruitment Detail

Type: Participants currently recruited/enrolled
Gender: Male & Female
Min Age: 18
Max Age: 70

Referral Letter Required


Population Exclusion(s)


Special Instructions

Currently Not Provided


Transcranial Magnetic Stimulation (TMS);
Magnetic Resonance Imaging (MRI);
Electroencephalogram (EEG);
Transcranial Electrical Stimulation (TES)

Recruitment Keyword(s)



Healthy Volunteers

Investigational Drug(s)


Investigational Device(s)



Device: TMS
Device: MRI

Supporting Site

National Institute of Neurological Disorders and Stroke


Little is known about the time it takes for nerve signals to go from one area of the brain to another. Using advanced methods for brain research, researchers want to look at the time it takes to send messages between different brain areas. They also want to develop new tests.


To develop tests to measure the sizes of nerve fibers in the peripheral nerve system and in the brain. Also to find out the different speeds that information travels in nerve fibers.


Healthy, right-handed people ages 18-70


Participants will be screened with medical history and a physical exam.

Participants will have up to 7 visits depending on the tests they choose. Visits last about 2-4 hours and may involve the following tests:

-Physical exam

-Urine tests

-Magnetic resonance imaging (MRI). Participants lie on a table that slides into a scanner. They will be in the scanner for up to 1 hour. For some scans, sensors are placed on the skin. They will get earplugs for loud noises.

-Small, sticky pads on the skin will electrically stimulate nerves in the forearm.

-Transcranial magnetic stimulation (TMS). A wire coil will be held to the scalp. A brief electrical current passes through the coil to affect brain activity.

-Electroencephalography. TMS will be given to the brain. Small electrodes on the scalp measure brain activity. Participants may do small tasks.

-Electrodes on the scalp will send an electrical current to the brain.

-A cone with magnetic detectors will be lowered onto the head to record brain activity. Participants will perform various tasks.

--Back to Top--



-Ages between 18-70 years.

-Right-handed (tested by the Edinburg handedness inventory).

-Able to give informed consent and able to comply with all study procedures.


-Self-reported consumption of >14 alcoholic drinks/week for a man and >7 alcoholic drinks/week for a woman.

-Abnormal findings on neurological examination.

-History of brain tumor, stroke, head trauma with loss of consciousness, epilepsy or seizures.

-Current episode of any major psychiatric illness.

-Use of medications that act directly on the CNS.

-Hearing loss reported in the history or detected in the routine physical examination

-Having permanent tattooed makeup (eyeliner, lip, etc.) or general tattoos. Subjects with tattoos will be excluded if those are in a dangerous location in the body or made with colors (e.g. dark blue and dark green) whose content in iron cannot be definitely ruled out by the investigators.

-Having non-organic implant or any other device such as: cardiac pacemaker, insulin infusion pump, implanted drug infusion device, cochlear, otologic, or ear implant, transdermal medication patch, any metallic implants or objects, body piercing(s), bone/joint pin, screw, nail, plate, wire sutures or surgical staples, shunt.

-Having cerebral or other aneurysm clips.

-Having shrapnel or other metal imbedded in the body (such as from war wounds or accidents).

-Had severe accidents in the past that may possibly have left metal in the body.

-Previously worked in metal fields or with machines that may have left any metallic fragments in or near eyes.

-Having any psychological contraindications for MRI (e.g., suffer from claustrophobia, unable to lie comfortably on your back for 2 hours).

-Discomfort being in a small space for the expected length of the experiment, up to 2 hours.


-NIH staff from HMCS in NINDS, Section on Quantitative Imaging and Tissue Sciences in NICHD or MEG Core facility in NIMH involved in the protocol.

--Back to Top--


Not Provided

--Back to Top--


Principal Investigator

Referral Contact

For more information:

Mark Hallett, M.D.
National Institute of Neurological Disorders and Stroke (NINDS)

Elaine P. Considine, R.N.
National Institute of Neurological Disorders and Stroke (NINDS)
National Institutes of Health
Building 10
Room 7D36
10 Center Drive
Bethesda, Maryland 20892
(301) 435-8518

Office of Patient Recruitment
National Institutes of Health Clinical Center (CC)
Building 61, 10 Cloister Court
Bethesda, Maryland 20892
Toll Free: 1-800-411-1222
Local Phone: 301-451-4383
TTY: 1-866-411-1010

Clinical Trials Number:


--Back to Top--