This randomized, double-blind, sham-controlled clinical trial will evaluate whether individualized alpha-frequency transcranial alternating current stimulation (tACS) can enhance the effects of mindfulness therapy in adults with generalized anxiety disorder. A total of 99 participants will be randomly assigned to one of three groups: synchronous tACS combined with mindfulness therapy, desynchronous tACS combined with mindfulness therapy, or sham tACS combined with mindfulness therapy.
All participants will receive a standardized mindfulness therapy program. The study will compare changes in anxiety symptoms, worry, mindfulness, attention control, cognitive performance, and neurophysiological measures across the three groups. Assessments will be conducted from baseline through follow-up visits to examine both clinical effects and possible neural mechanisms.
Outpatients or inpatients of The Second Xiangya Hospital of Central South University.
Diagnosis of generalized anxiety disorder as the primary diagnosis according to the International Classification of Diseases 11th Revision (ICD-11) diagnostic criteria, confirmed by two experienced psychiatrists.
Hamilton Anxiety Rating Scale (HAMA) total score of 14 or higher.
Aged 18 to 60 years, inclusive.
Presence of psychotic symptoms.
Meeting ICD-11 diagnostic criteria for schizophrenia or other primary psychotic disorders, bipolar or related disorders, current depressive episode, dysthymic disorder, or post-traumatic stress disorder currently or within the past year.
Organic brain disease or severe physical illness, including but not limited to thyroid disease, systemic lupus erythematosus, diabetes, severe pulmonary, hepatic, or renal impairment, infection, or major trauma.
Clinically significant uncorrectable sensory impairment, such as hearing impairment that prevents effective communication.
Parallel
Synchronous Individualized Alpha-Frequency tACS
DeviceIndividualized alpha-frequency transcranial alternating current stimulation (tACS) will be delivered to the frontoparietal network. Stimulation electrodes will be placed over F3 and P3, corresponding to the left dorsolateral prefrontal cortex and left inferior parietal lobule. In the synchronous tACS condition, the F3 and P3 stimulation electrodes will deliver in-phase sinusoidal alternating current. The stimulation frequency will be individualized based on each participant's alpha-band phase locking value peak between F3 and P3.
Desynchronous Individualized Alpha-Frequency tACS
DeviceIndividualized alpha-frequency tACS will be delivered using the same stimulation targets and general setup as the synchronous tACS condition. Stimulation electrodes will be placed over F3 and P3, corresponding to the left dorsolateral prefrontal cortex and left inferior parietal lobule. In the desynchronous tACS condition, the phase difference between the F3 and P3 stimulation electrodes will be set at 180 degrees.
Sham tACS
DeviceSham tACS will be delivered with the electrodes placed in the same positions as in the active tACS conditions. The sham condition will include 30-second ramp-up and ramp-down periods at the beginning and end of stimulation to mimic the sensation of active stimulation. No active current will be delivered during the main 20-minute stimulation period, while the electrodes will remain in place to maintain blinding.
Mindfulness Therapy
BehavioralParticipants will receive a standardized mindfulness therapy program for 2 weeks, with 10 sessions in total. Each session will last 40 minutes. The program follows a progressive structure of awareness, acceptance, and application. The first five sessions focus on breath awareness and body scan practices. The last five sessions focus on observing anxiety-related bodily sensations and worry-related thoughts with a nonjudgmental and accepting attitude, and on using breathing space practices to redirect attention to the present moment.
Change from baseline in Hamilton Anxiety Rating Scale total score at Week 2 post-randomization
The Hamilton Anxiety Rating Scale (HAMA) is a clinician-administered scale used to assess the severity of anxiety symptoms. The total score ranges from 0 to 56, with higher scores indicating more severe anxiety symptoms. This outcome is defined as the change in HAMA total score from baseline to Week 2 post-randomization, calculated as the Week 2 score minus the baseline score. A greater reduction indicates greater improvement in anxiety symptoms.
Change in Generalized Anxiety Disorder-7 Score From Baseline to Follow-up
The Generalized Anxiety Disorder-7 (GAD-7) is a 7-item self-report questionnaire used to assess the severity of anxiety symptoms. The total score ranges from 0 to 21, with higher scores indicating greater anxiety severity.
Change in Penn State Worry Questionnaire Score From Baseline to Follow-up
The Penn State Worry Questionnaire (PSWQ) is a 16-item self-report questionnaire used to assess the tendency to engage in excessive and uncontrollable worry. The total score ranges from 16 to 80, with higher scores indicating greater worry severity.
Change in Five Facet Mindfulness Questionnaire Score From Baseline to Follow-up
The Five Facet Mindfulness Questionnaire (FFMQ) is a self-report questionnaire used to assess mindfulness-related abilities,including observing, describing, acting with awareness, non-judging, and non-reactivity.. For the standard 39-item version, the total score ranges from 39 to 195, with higher scores indicating a higher level of mindfulness.
Change in Attentional Control Scale Score From Baseline to Follow-up
The Attentional Control Scale (ACS) is a 20-item self-report questionnaire used to assess perceived ability to focus and shift attention. The total score ranges from 20 to 80, with higher scores indicating better attentional control.
Click on the lead sponsor to view all of their trials.
This trial is not recruiting at the moment. You can still explore other options:
