The Effect of Transcranial Direct Current Stimulation (tDCS) in Improving Emotion Health

NCT07319143 | Recruiting

• 2 other identifiers: EA24067017600425
• Study Type: interventional
• Target: 90
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to investigate how transcranial direct current stimulation (tDCS) affects emotion functions in young adults aged 18-35 from the local community, including both male and female participants. The main question\[s\] it aims to answer are:

• Does tDCS improve emotional functions, such as mood regulation and motivation, in individuals with subthreshold depression (StD)?
• Can tDCS enhance emotional regulation compared to a sham stimulation (placebo)? Researchers will compare participants receiving tDCS on either the left dorsolateral prefrontal cortex (lDLPFC) or right ventrolateral prefrontal cortex (rVLPFC) with those receiving sham stimulation to see if tDCS has a stronger effect on emotional functions. Participants will:
• Complete online and in-person screening to assess depressive symptoms using the Chinese version of the Beck Depression Inventory II (C-BDI-II) and be selected based on their depressive symptoms (C-BDI-II score ≥ 13).
• Be randomly assigned to one of three groups: lDLPFC tDCS, rVLPFC tDCS, or Sham control group (1:1:1 ratio).
• Receive 10 sessions of tDCS or Sham tDCS over 2 weeks, with each session lasting 20 minutes.
• Complete assessments at baseline, post-intervention, 1-month follow-up, and 3-month follow-up, with each assessment lasting 2-2.5 hours. This includes questionnaires and perform emotional and cognitive tasks.

Conditions

Subthreshold Depression; Positive Emotions; Negative Emotions; Anhedonia

Keywords

Transcranial Direct Current Stimulation; Subthreshold Depression; Emotion; Neuromodulation

Outcome Measures

Primary Outcomes (1)

• Depressive symptoms

  The Beck Depression Inventory-II Chinese Version measures change in depressive symptoms. The total score range is 0-63, higher score indicates more severe depressive symptoms.

  Baseline (Day 1), Post-Intervention (Day 15), 1-Month Follow-up (Day 45), 3-Month Follow-up (Day 105)

Secondary Outcomes (15)

• Affective trait

  Baseline (Day 1), Post-Intervention (Day 15), 1-Month Follow-up (Day 45), 3-Month Follow-up (Day 105)

• Anhedonia severity

  Baseline (Day 1), Post-Intervention (Day 15), 1-Month Follow-up (Day 45), 3-Month Follow-up (Day 105)

• Anhedonia symptoms

  Baseline (Day 1), Post-Intervention (Day 15), 1-Month Follow-up (Day 45), 3-Month Follow-up (Day 105)

• Behavioural motivation trait

  Baseline (Day 1), Post-Intervention (Day 15), 1-Month Follow-up (Day 45), 3-Month Follow-up (Day 105)

• Emotion regulation function

  Baseline (Day 1), Post-Intervention (Day 15), 1-Month Follow-up (Day 45), 3-Month Follow-up (Day 105)

Study Arms (3)

IDLPFC tDCS

EXPERIMENTAL

This intervention is a 20 minutes per session, two-week tDCS neuromodulation of IDLPFC region (anode: F3, cathode: FP2) designed to reduce depressive symptoms via enhancing positive emotion functions, thereby reducing anhedonia.

Device: Transcranial Direct Current Stimulation

rVLPFC tDCS

EXPERIMENTAL

This intervention is a 20 minutes per session, two-week tDCS neuromodulation of rVLPFC region (anode: F6, cathode: FP1) designed to reduce depressive symptoms via regulating negative emotion functions, thereby reducing depressed mood.

Device: Transcranial Direct Current Stimulation

Sham tDCS

SHAM COMPARATOR

This is a 20 minutes per session, two-week Sham comparator of IDLPFC/rVLPFC region, participants will receive tDCS for 30 seconds at either IDLPFC/rVLPFC at the beginning of each session to stimulate real neuromodulation.

Device: Sham tDCS

Interventions

Transcranial Direct Current Stimulation DEVICE

TDCS is a non-invasive, safe, inexpensive, convenient and effective method to modulate brain and emotion functions. During tDCS, a mild electric current is passed between the anodal and cathodal electrodes on the scalp, which respectively excites and inhibits local and downstream neuronal activity, as well as modulating interregional connectivity strength. Compared to other neurostimulation methods such as Transcranial Magnetic Stimulation, tDCS side effects tend to be milder and transient, even if being administered for multiple sessions, making it suitable to be widely applied on clinical and subclinical populations.

Also known as: tDCS

IDLPFC tDCS; rVLPFC tDCS

Sham tDCS DEVICE

The sham tDCS delivers actual stimulation for 30 seconds only, while providing similar psychological perceptions to participants as the real intervention. Thus, the sham tDCS serves as an active control condition to the tDCS interventions.

Sham tDCS

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Age 18-35 years
• Fluency in Cantonese or Mandarin
• Normal or corrected-to-normal vision and hearing
• IQ \> 75% Quantile in Raven's SPM
• At least 9 years of formal education
• Right-handedness

You may not qualify if:

• Past or current major physical illness or psychiatric disorders
• Use of psychotropic medication in the past 6 months
• Pregnancy (for women)
• Any condition that prevents safe tDCS use (e.g., brain injury, implants)
• Previous participation in neuromodulation in the past 3 months

Sponsors & Collaborators

• The University of Hong Kong: lead
• Research Grants Council, Hong Kong: collaborator

Study Sites (1)

The University of Hong Kong

Hong Kong, Hong Kong

RECRUITING

MeSH Terms

Conditions

Anhedonia

Interventions

Transcranial Direct Current Stimulation

Condition Hierarchy (Ancestors)

Neurobehavioral Manifestations; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Electric Stimulation Therapy; Therapeutics; Convulsive Therapy; Psychiatric Somatic Therapies; Behavioral Disciplines and Activities; Electroshock; Psychological Techniques

Central Study Contacts

Associate Professor, Principle Investigator

CONTACT

+852-3917-8927; rshao@hku.hk

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: December 6, 2025
• First Posted: January 6, 2026
• Study Start: January 8, 2026
• Primary Completion (Estimated): September 1, 2027
• Study Completion (Estimated): September 1, 2027
• Last Updated: May 4, 2026

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

HK (1)