HD-tDCS to Modulate Connectivity
Study Details
Study Description
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.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
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.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: 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. |
Device: high definition transcranial direct current stimulation (HD-tDCS)
HD-tDCS will be provided for 20 minutes for each stimulation with peak intensity of 2mA.
|
| Experimental: 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. |
Device: high definition transcranial direct current stimulation (HD-tDCS)
HD-tDCS will be provided for 20 minutes for each stimulation with peak intensity of 2mA.
|
| Experimental: 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. |
Device: high definition transcranial direct current stimulation (HD-tDCS)
HD-tDCS will be provided for 20 minutes for each stimulation with peak intensity of 2mA.
|
| Experimental: 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. |
Device: high definition transcranial direct current stimulation (HD-tDCS)
HD-tDCS will be provided for 20 minutes for each stimulation with peak intensity of 2mA.
|
| Sham Comparator: 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. |
Device: high definition transcranial direct current stimulation (HD-tDCS)
HD-tDCS will be provided for 20 minutes for each stimulation with peak intensity of 2mA.
|
Outcome Measures
Primary Outcome Measures
- change of functional connectivity [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 Outcome Measures
- change of cerebral blood flow [12-16 minutes after the stimulation contrasting baseline (before stimulation)]
Changes in Cerebral Blood Flow (estimated using pseudo continuous arterial spin labeling )
- Toronto Mindfulness Scale (curiosity) [Baseline, then within 1-2 hours from stimulation]
mindfulness scale for curiosity. min: 0, max: 30. Higher score means higher curiosity-mindfulness.
- Toronto Mindfulness Scale (decentering) [Baseline, then within 1-2 hours from stimulation]
mindfulness scale for decentering. min: 0, max: 35. Higher score means higher decentering-mindfulness.
Eligibility Criteria
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
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | University of Manitoba | Winnipeg | Manitoba | Canada | R3E 0J9 |
Sponsors and Collaborators
- University of Manitoba
- Natural Sciences and Engineering Research Council, Canada
Investigators
None specified.Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- HS24853