Exploring the Relationship Between Brain Asymmetry and Attention
- Conditions
- Normal Physiology
- Interventions
- Device: TMS EEGDevice: TMS fMRI
- Registration Number
- NCT03789201
- Brief Summary
Background:
People tend to pay more attention to one side of space than the other and this may be due to differences in the structure and function of the two sides of the brain. We are interested in whether we can detect those difference with magnetic resonance imaging (MRI), transcranial magnetic stimulation (TMS), and electroencephalography (EEG).
Objective:
The purpose of the study is to understand how differences in brain structure may cause people to pay more attention to one side than the other.
Eligibility:
Healthy adults ages 18-35
Design:
Participants will be screened with a neurological exam.
Participants will have 2-3 visits for a total duration of about 7/8 hours.
Women of childbearing age must have a negative pregnancy test before each MRI scan.
Visits may include:
Physical exam
Tests of attention, and thinking
TMS. A brief electrical current will pass through a wire coil on the scalp. Participants will hear a click and may feel a pull. They may be asked to tense muscles or do tasks.
Magnetic resonance imaging (MRI) scan for a maximum of 1 hour. Participants will lie on a table that slides into a cylinder in a strong magnetic field. They will do tasks on a computer screen or lie still. They will get earplugs for loud noise.
EEG for no longer than 5 hours, with most lasting 3 hours. Gel and a cap with electrodes will be placed on the scalp. They will record brain waves while the participant gets TMS or does nothing.
Questions about participants dominant hand and about the MRI.
- Detailed Description
Objective
The goal of this protocol to explore correlations between lateralized individual differences in visual attentional preference and hemispheric asymmetries in functional connectivity between the frontal and parietal visual attention areas. To measure functional connectivity, resting state functional MRI and electroencephalographic (EEG) potentials evoked with transcranial magnetic stimulation (TMS) will be used. Protocol research will also attempt to validate the TMS-evoked EEG potentials against fMRI resting state functional connectivity.
Study Population
Up to 80 right-handed and right-eyed healthy volunteers, aged 18-35
Design
TMS evoked EEG potentials (TEPs) and fMRI will be used to measure functional connectivity between the posterior parietal cortex and the frontal visual attention area. Various tasks will be used to quantify attention and explore their relationship with asymmetries in functional connectivity. A qualitative comparison between the value of fMRI and TEPs for predicting attentional bias will be made.
Outcome Measures
* Behavioral measures of attention
* TEP measures of functional connectivity
* fMRI measures of functional connectivity
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 45
Not provided
Not provided
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- SINGLE_GROUP
- Arm && Interventions
Group Intervention Description Healthy Volunteers TMS fMRI thematic permission to use non-invasive techniques regarded as having minimal risk in healthy individuals, such as, MRI, EEG, EMG, low-frequency stimulation (= 1 Hz), electrical stimulation of the skin to mimic the somatosensory artifact of TMS, and behavioral tests Healthy Volunteers TMS EEG thematic permission to use non-invasive techniques regarded as having minimal risk in healthy individuals, such as, MRI, EEG, EMG, low-frequency stimulation (= 1 Hz), electrical stimulation of the skin to mimic the somatosensory artifact of TMS, and behavioral tests
- Primary Outcome Measures
Name Time Method Exploratory sub-studies under this protocol will answer questions about how to optimize EEG recordings of the cortical response to TMS. 20 visits Response to TMS
- Secondary Outcome Measures
Name Time Method
Trial Locations
- Locations (1)
National Institutes of Health Clinical Center
🇺🇸Bethesda, Maryland, United States