Modulating Functional Brain Connectivity Using High Definition Transcranial Direct Current Stimulation (HD-tDCS)
Overview
- Phase
- Not Applicable
- Intervention
- high definition transcranial direct current stimulation (HD-tDCS)
- Conditions
- Electricity; Effects
- Sponsor
- University of Manitoba
- Enrollment
- 100
- Locations
- 2
- Primary Endpoint
- change of functional connectivity
- Status
- Recruiting
- Last Updated
- yesterday
Overview
Brief Summary
The purpose of the proposed study is to broaden our understanding on the neural effects of High Definition Transcranial Direct Current Stimulation (HD-tDCS) so that its clinical effects can be further improved.
Detailed Description
Normal healthy individuals will be recruited and undergo a standardized neuropsychological assessment (ANAM, MoCA, BDI-II, ToMS, and MAAS) and magnetic resonance imaging (MRI). During MRI, HD-tDCS will be applied. Four different stimulation targets will be investigated, and subjects will be randomly assigned for each target groups or sham group. After HD-tDCS/MRI session, subjects will be re-assessed with standardized neuropsychological tests.
Investigators
Eligibility Criteria
Inclusion Criteria
- •\- All other than excluded.
Exclusion Criteria
- •History or susceptibility to any neurological or psychiatric diseases, particularly seizures
- •abnormal MRI
- •metal implants or a cardiac pacemaker
- •pregnant or breastfeeding women
Arms & Interventions
left DLPFC stimulation
HD-tDCS will be used to deliver direct current to the target via rubber electrodes and HD-tDCS gels. The 9 electrodes (8 channels + 1 ground) positions and current intensity will be determined based on computer simulation using HDTargets software (Soterix Inc.) that results in maximum focal current on the left dorsolateral prefrontal cortex (DLPFC; x=-44, y=10, z=30) with inward field orientation. The peak current will not exceed 2 mA. A constant current will be delivered for 20 minutes.
Intervention: high definition transcranial direct current stimulation (HD-tDCS)
right DLPFC stimulation
HD-tDCS will be used to deliver direct current to the target via rubber electrodes and HD-tDCS gels. The 9 electrodes (8 channels + 1 ground) positions and current intensity will be determined based on computer simulation using HDTargets software (Soterix Inc.) that results in maximum focal current on the right dorsolateral prefrontal cortex (DLPFC; x=+42, y=+14, z=+30) with inward field orientation. The peak current will not exceed 2 mA. A constant current will be delivered for 20 minutes.
Intervention: high definition transcranial direct current stimulation (HD-tDCS)
left IPL stimulation
HD-tDCS will be used to deliver direct current to the target via rubber electrodes and HD-tDCS gels. The 9 electrodes (8 channels + 1 ground) positions and current intensity will be determined based on computer simulation using HDTargets software (Soterix Inc.) that results in maximum focal current on the left intraparietal lobe (IPL; x=-50, y=-36, z=+42) with inward field orientation. The peak current will not exceed 2 mA. A constant current will be delivered for 20 minutes.
Intervention: high definition transcranial direct current stimulation (HD-tDCS)
VLPFC-PCC stimulation
HD-tDCS will be used to deliver direct current to the target via rubber electrodes and HD-tDCS gels. The 9 electrodes (8 channels + 1 ground) positions and current intensity will be determined based on computer simulation using HDTargets software (Soterix Inc.) that results in maximum focal current on the left ventrolateral prefrontal cortex (VLPFC; x=-50, y=+26, z=+8) and posterior cingulate cortex (PCC; x=1, y=-61, z=38) with inward field orientation. The peak current will not exceed 2 mA. A constant current will be delivered for 20 minutes.
Intervention: high definition transcranial direct current stimulation (HD-tDCS)
Sham stimulation
One of the above three targets will be randomly selected. The current will be applied for 30 seconds ramp-up followed by 30 seconds ramp-down.
Intervention: high definition transcranial direct current stimulation (HD-tDCS)
Outcomes
Primary Outcomes
change of functional connectivity
Time Frame: 0-11 minutes after the stimulation contrasting baseline (before stimulation)
Changes in seed-based connectivity originating from the targeted brain regions immediately after the brain stimulation
Secondary Outcomes
- change of cerebral blood flow(12-16 minutes after the stimulation contrasting baseline (before stimulation))
- Toronto Mindfulness Scale (curiosity)(Baseline, then within 1-2 hours from stimulation)
- Toronto Mindfulness Scale (decentering)(Baseline, then within 1-2 hours from stimulation)