Effects of tDCS on Fear Reversal in Patients With Anxiety Disorders
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Cathodal tDCS (rDLPFC), Anodal tDCS (vmPFC), Sham tDCS, Anodal tDCS (lDLPFC).
- Who it may be relevant to
- Registry conditions: Anxiety Disorders. Basic parameters: 18 years — 65 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- China
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
A Randomized, Double-Blind, Controlled Study of Transcranial Direct Current Stimulation Intervention on Fear Reversal in Patients With Anxiety Disorders
Overview
This study evaluates the effects of single-session Transcranial Direct Current Stimulation (tDCS) on fear reversal learning in patients with anxiety disorders. Participants will be randomized into four groups to receive either active stimulation targeting specific brain regions (right DLPFC or vmPFC), an active control stimulation, or sham stimulation. The main goal is to determine if modulating these brain areas can improve the ability to update safety and threat associations.
Detailed description
Anxiety disorders are characterized by deficits in fear regulation and cognitive flexibility, specifically the inability to inhibit fear responses when a threat becomes safe (fear reversal). Neurobiological models suggest this is linked to hyperactivity in the right dorsolateral prefrontal cortex (rDLPFC) and hypoactivity in the ventromedial prefrontal cortex (vmPFC).
This randomized, double-blind, sham-controlled study aims to verify if tDCS can improve fear reversal performance. The study involves 140 patients with anxiety disorders assigned to one of four arms:
Cathodal tDCS over the right DLPFC (inhibitory); Anodal tDCS over the vmPFC (excitatory); Sham tDCS (placebo); Anodal tDCS over the left DLPFC (active control). During the 25-minute stimulation session, participants will perform a computerized fear reversal task. Physiological data (Skin Conductance Response) and subjective anxiety ratings will be recorded simultaneously to assess the intervention's impact on cognitive and emotional regulation.
Interventions
- Device Cathodal tDCS (rDLPFC)
Current intensity: 2.0 mA. Duration: 25 minutes. Cathode placed over F4 (10-20 system), Anode over contralateral deltoid. - Device Anodal tDCS (vmPFC)
Current intensity: 2.0 mA. Duration: 25 minutes. Anode placed over Fpz (10-20 system), Cathode over Oz. - Device Sham tDCS
Current ramps up for 30 seconds and then fades to zero to mimic skin sensation, with no sustained current for the rest of the 25 minutes. - Device Anodal tDCS (lDLPFC)
Current intensity: 2.0 mA. Duration: 25 minutes. Anode placed over F3 (10-20 system), Cathode over contralateral deltoid.
Primary outcome measures
- Mean Accuracy Rate in the Reversal Phase of the Fear Reversal Task [Time frame: During the intervention (Day 1, approximately 25 minutes)]
Secondary outcome measures (3)
- Reaction Time in the Reversal Phase [Time frame: During the intervention (Day 1, approximately 25 minutes)]
- Skin Conductance Response (SCR) Amplitude [Time frame: During the intervention (Day 1, approximately 25 minutes)]
- Subjective Anxiety Score (VAS) [Time frame: During the intervention (Day 1, assessed intermittently during the 25-minute task)]
Eligibility criteria
Inclusion criteria
Age between 18 and 60 years old. Right-handed. Meeting the DSM-5 diagnostic criteria for Gambling Disorder (GD). South Oaks Gambling Screen (SOGS) score ≥ 5. Normal or corrected-to-normal vision and hearing. Willingness to provide written informed consent and participate in the study.
Exclusion criteria
History of other severe psychiatric disorders (e.g., schizophrenia, bipolar disorder, severe depression) or neurological diseases (e.g., epilepsy, stroke, brain tumor).
History of substance abuse or dependence (excluding nicotine) in the past 6 months.
Current use of psychotropic medications that may affect cortical excitability (e.g., antidepressants, antipsychotics, anticonvulsants).
Presence of metallic implants in the head or neck area (e.g., cochlear implants, aneurysm clips) or cardiac pacemakers.
Skin lesions or sensitivity at the stimulation sites on the scalp. Pregnancy or lactation. Participation in other neuromodulation studies within the last 3 months.
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Allocation
- Randomized
- Model
- Parallel assignment
- Masking
- Triple blind
- Primary purpose
- Treatment
Study locations
China · 1 center
- Shenzhen Kangning Hospital — Guangzhou
Identifiers
NCT: NCT07405463 · KN2025407