NCT07405463

Effects of tDCS on Fear Reversal in Patients With Anxiety Disorders

A Randomized, Double-Blind, Controlled Study of Transcranial Direct Current Stimulation Intervention on Fear Reversal in Patients With Anxiety Disorders

• Status: Enrolling By Invitation
• Phase: N/A
• Study type: Interventional
• Enrollment: 140 (estimated)
• Sponsor: Jingchu Hu · Academic / Other
• Sex: All
• Age: 18 Years – 65 Years
• Healthy volunteers: Accepted

Summary

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.

Conditions

• Anxiety Disorders

Interventions

Type	Name	Description
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.

Timeline

• Start date: 2025-12-01
• Primary completion: 2028-12-01
• Completion: 2028-12-01
• First posted: 2026-02-12
• Last updated: 2026-02-12

Locations

1 site across 1 country: China