Subthreshold Depression
Conditions
Brief summary
This study evaluates the effects of multi-session transcranial direct current stimulation on loneliness, mood and depressiveness in people with subthreshold depression.
Detailed description
Depression-prone individuals will be invited and allocated to three groups, either the personalised transcranial direct current stimulation (tDCS) group, the conventional tDCS group, or the sham control group. After screening and at baseline prior to the tDCS sessions, participants will complete tests and questionnaires on depression symptoms, loneliness and mood. Eligible participants will also be invited to receive functional magnetic resonance imaging (MRI) in a 3-Tesla MRI scanner. There will be a maximum of 10 sessions to be completed after the screening and baseline measures. For both personalised tDCS group and the conventional tDCS group, tDCS with 2 milliampere (mA) intensity will be delivered for 20 minutes in each session. For sham control group, the protocol will be similar, except that the stimulation only happens in the first 30 seconds in each session. Especially for participants allocated to the personalised tDCS group, the stimulation site for each individual in this group may vary, depending on their brain activations and connectivity. The anodal stimulation sites for participants allocated to the conventional tDCS group and the sham control group will be F3 within the left DLPFC. Immediately after and also 3-months after completing all the tDCS sessions, participants will be invited to complete again tests and questionnaires on depressive symptoms in addition to loneliness and mood. Eligible participants will also be invited to receive functional MRI scanning in the 3T MRI scanner again. Participants will also be prompted to self-report daily their loneliness and mood levels throughout the study.
Interventions
DEVICEPersonalized Experimental Transcranial Direct Current Stimulation (tDCS)
This study will deliver tDCS sessions for a maximum of ten sessions in two weeks' time. Participants will receive 20 minutes of active stimulation with a 2mA intensity over personalized brain regions based on the particular neural correlates of socio-affective processing.
DEVICESham Transcranial Direct Current Stimulation (tDCS)
This study will deliver tDCS sessions for a maximum of ten sessions in two weeks' time. Participants assigned to the sham control group will only receive 30 seconds of active stimulation.
DEVICEConventional Experimental Transcranial Direct Current Stimulation (tDCS)
This study will deliver tDCS sessions for a maximum of ten sessions in two weeks' time. Participants will receive 20 minutes of active stimulation with a 2mA intensity with anode placed over F3.
Sponsors
Education University of Hong Kong
The University of Hong Kong
Chinese University of Hong Kong
Hong Kong Baptist University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* No histories of learning impairment, major psychiatric disorders including Major Depressive Disorder or neurological disorders * At least primary school education * Subthreshold depression
Exclusion criteria
* On medication or treatments within 2 weeks prior to the beginning of the study that would affect the individual's brain, cognitive and affective functions
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in self-reported loneliness | From baseline to after the last tDCS session; from baseline to 3 months after the last tDCS session | Loneliness is assessed based on the University of California, Los Angeles (UCLA) loneliness scale and single item, in which higher scores indicate greater degrees of loneliness. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Changes in depressive symptoms | From baseline to after the last tDCS session; from baseline to 3 months after the last tDCS session | Depressive symptoms are assessed based on the Hospital Anxiety and Depression Scale, a 14-item scale assessing severity of depressive and anxiety symptom (score range 0 - 21 for both subscale), with a higher scores indicating higher severity |
| Changes in anxiety symptoms | From baseline to after the last tDCS session; from baseline to 3 months after the last tDCS session | Anxiety symptoms are assessed based on the Hospital Anxiety and Depression Scale, a 14-item scale assessing severity of depressive and anxiety symptom (score range 0 - 21 for both subscale), with a higher scores indicating higher severity |
| Changes in self-reported mood | From baseline to after the last tDCS session; from baseline to 3 months after the last tDCS session | Mood is assessed based on the Chinese Affect Scale, a 20-item 5-point Likert scale where participants rate the degree to which they currently feel the listed affects (scoring for each item: 0 = no at all; 4 = very). |
| Changes in brain activation and connectivity | From baseline to after the last tDCS session; from baseline to 3 months after the last tDCS session | Neural activities and connectivity in Ventral Attention Network, Frontoparietal Network, and Default Mode Network are assessed by functional MRI |
Countries
Hong Kong
Contacts
CONTACTNichol ML Wong, PhD
PRINCIPAL_INVESTIGATORNichol ML Wong, PhD
Education University of Hong Kong
Outcome results
None listed