Healthy Subjects
Conditions
Brief summary
The purpose of this study is to investigate the modulatory effects of repetitive transcranial magnetic stimulation (rTMS) on functional connectivity with the insula. Functional connectivity (FC) measures the interaction between brain regions, and recent neuroimaging studies have used FC to investigate how addiction affects FC among pertinent brain regions. rTMS, which can excite cortical neurons, has shown promise as a method to manipulate brain connectivity and could be used therapeutically to treat addiction. However, investigators first need more information on brain FC and how it relates to behavior, in order to guide rTMS target selection.
Interventions
DEVICEtranscranial magnetic stimulation
Sponsors
Duke University
Study design
Allocation
RANDOMIZED
Intervention model
FACTORIAL
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to 55 Years
Healthy volunteers
Yes
Inclusion criteria
* generally healthy * between the ages of 18-55 * right-handed
Exclusion criteria
* significant health problems (e.g., current and uncontrolled liver, lung, or heart problems) or presence of medical illness likely to alter brain morphology (including history of seizure, history of epilepsy in self or first degree relatives, stroke, brain surgery, head injury, and known structural brain lesion) * current diagnosis of Axis I psychiatric disorders (e.g., depression, anxiety disorder, schizophrenia) * meet DSM-5 criteria for current substance use disorder other than nicotine * use of psychoactive medications that would result in a positive urine drug screen * Current use of medications known to lower the seizure threshold * positive breath alcohol concentration * presence of conditions that would make MRI unsafe (e.g., metal implants, pacemakers) * among women, a positive urine pregnancy test * vision that cannot be corrected to 20/40
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Functional Connectivity Strength Measured With Functional Magnetic Resonance Imaging | baseline and 1 week | Difference in functional connectivity from the TMS target site to the right insula. The primary dependent variable was the resting-state functional connectivity strength between the TMS target site and the right insula. |
Countries
United States
Participant flow
Pre-assignment details
5 subjects were consented but did not meet eligibility criteria and were not randomized to a condition.
Participants by arm
| Arm | Count |
|---|---|
| 10 Hz TMS This group received 10 Hz TMS | 6 |
| 1 Hz TMS This group received 1 Hz TMS | 25 |
| Total | 31 |
Baseline characteristics
| Characteristic | 10 Hz TMS | 1 Hz TMS | Total |
|---|---|---|---|
| Age, Continuous | 27 years STANDARD_DEVIATION 7 | 31 years STANDARD_DEVIATION 12 | 30 years STANDARD_DEVIATION 11 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 1 Participants | 3 Participants | 4 Participants |
| Race (NIH/OMB) Black or African American | 0 Participants | 7 Participants | 7 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 1 Participants | 1 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 5 Participants | 14 Participants | 19 Participants |
| Region of Enrollment United States | 6 Participants | 25 Participants | 31 Participants |
| Sex: Female, Male Female | 3 Participants | 18 Participants | 21 Participants |
| Sex: Female, Male Male | 3 Participants | 7 Participants | 10 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 6 | 0 / 25 |
| other Total, other adverse events | 0 / 6 | 0 / 25 |
| serious Total, serious adverse events | 0 / 6 | 0 / 25 |
Outcome results
Primary
Change in Functional Connectivity Strength Measured With Functional Magnetic Resonance Imaging
Difference in functional connectivity from the TMS target site to the right insula. The primary dependent variable was the resting-state functional connectivity strength between the TMS target site and the right insula.
Time frame: baseline and 1 week
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| 10 Hz TMS | Change in Functional Connectivity Strength Measured With Functional Magnetic Resonance Imaging | .25 correlation coefficient |
| 1 Hz TMS | Change in Functional Connectivity Strength Measured With Functional Magnetic Resonance Imaging | .13 correlation coefficient |