Transcranial magnetic stimulation (TMS) is form of non-invasive brain stimulation. It is
approved to treat depression. TMS may help decrease drug craving. It is important to
understand how TMS affects the brain. Such a better understanding would help to design ways
to treat drug addiction.
To learn how TMS affects the brain when it stimulates an area in the front of the brain.
Also, to see how the stimulation affects the area stimulated and other connected areas.
Healthy, right-handed adults ages 18 60 who are non-drug users.
Participants will be screened under protocol 06-DA-N415.
Participants will have at least 3 visits. The first visit will last about 3 hours. All other
visits will last up to 6 hours. Participants cannot use drugs or alcohol at least 24 hours
before a visit. They cannot have more than half a cup of a caffeinated drink at least 12
hours before a visit.
Each visit will include a brief medical history update, urine test for drugs and pregnancy
(if female), a breath test for alcohol and smoking, and questionnaires.
Participants will have a TMS orientation visit. A wire coil will be placed on the head. An
electrical current will pass through the coil to create a magnetic pulse that stimulates the
The other visits will include 2 sessions of TMS-MRI. Participants will lie on a table that
slides into a cylinder. The TMS coil and the MRI coil will be placed over the head. Pictures
will be taken of the brain with and without stimulation.
Participants will complete a questionnaire about how they feel before and after each TMS
session and in a follow-up call 2 3 weeks after their last session.
Objectives: The goal of the protocol is to investigate acute modulations of brain activity by
transcranial magnetic stimulation (TMS). Using simultaneous TMS and functional magnetic
resonance imaging (fMRI), we will evaluate TMS induced changes in brain activity, including
regional brain activation and inter-regional functional connectivity. Repetitive TMS will be
applied over the dorsolateral prefrontal cortex (DLPFC) with different frequencies and
interleaved with fMRI acquisition to provide online monitoring of brain activity.
Furthermore, we will assess the relationship between the TMS induced brain activity and the
anatomical connection obtained from diffusion tensor imaging (DTI), using individual
variations in these imaging measures. Results from this study will help to understand the
underling mechanism of TMS and will provide insights for interpretation of TMS and fMRI data.
Study population: Up to 70 healthy, adults will be tested. Subjects must fit
exclusion/inclusion criteria for both TMS and MRI. We expect to enroll 70 subjects to arrive
at 50 who complete the protocol. Design: The study is a within-subject design with each
subject completing up to 4 TMS-fMRI sessions in two days (2 sessions per day) Outcome
measures: The outcome measures will be the effects of TMS on fMRI blood oxygen
level-dependent (BOLD) responses, TMS induced changes on resting state functional
connectivity, and their associations with relevant structural connectivity revealed by DTI.
If you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.
Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.