HD-tDCS to Modulate Connectivity

Not Applicable

Recruiting

• Conditions: Electricity; Effects
• Interventions: Device: high definition transcranial direct current stimulation (HD-tDCS)

• Registration Number: NCT05959551
• Lead Sponsor: University of Manitoba

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.

Study Timeline

• Study First Submitted: 2023-06-20
• Study Start: 2023-07-01
• Study First Submitted QC: 2023-07-17
• Study First Posted: 2023-07-25
• Status Verified: 2024-12
• Last Update Submitted: 2024-12-03
• Last Update Posted: 2024-12-06
• Primary Completion: 2025-08-31
• Study Completion: 2025-08-31

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 100

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

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
left DLPFC stimulation	high definition transcranial direct current stimulation (HD-tDCS)	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.
VLPFC-PCC stimulation	high definition transcranial direct current stimulation (HD-tDCS)	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.
right DLPFC stimulation	high definition transcranial direct current stimulation (HD-tDCS)	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.
left IPL stimulation	high definition transcranial direct current stimulation (HD-tDCS)	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.
Sham stimulation	high definition transcranial direct current stimulation (HD-tDCS)	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.

Primary Outcome Measures

Name	Time	Method
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

Name	Time	Method
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.

Trial Locations

Locations (1)

University of Manitoba; 🇨🇦 Winnipeg, Manitoba, Canada