Navigated cTBS for the Treatment of Generalized Anxiety Disorder

Condition(s) studied

Investigational drug(s) / intervention(s)

Mapsd Continuous Theta Burst Stimulation: A non-invasive brain stimulation technique using a MagStim Rapid2 stimulator with a 70mm air-cooled figure-of-eight coil. The stimulation target is the left auditory association cortex (MNI: -62, -40, 10), located using a Brainsight neuronavigation system. The cTBS protocol consists of 3-pulse 50 Hz bursts repeated at a 5 Hz frequency for a total of 600 pulses, delivered at 100% of the individual's resting motor threshold (RMT).

Sham Navigated Continuous Theta Burst Stimulation: A placebo procedure using an inert sham coil that is identical in appearance and sound to the active coil but does not deliver a significant magnetic field to the cortex. All other aspects of the procedure, including neuronavigation, coil placement, duration, and sound, are identical to the active intervention to maintain the blind.

Study summary

The purpose of this study is to investigate the effectiveness of a non-invasive brain stimulation technique called continuous Theta Burst Stimulation (cTBS) for treating Generalized Anxiety Disorder (GAD). The researchers will use a neuronavigation system, which acts like a GPS for the brain based on a participant's own MRI scan, to guide the stimulation to a specific target in the brain's auditory association cortex. This area is involved in processing information and may play a role in anxiety.

Participants who enroll will be randomly assigned to one of two groups. One group will receive active cTBS treatment, while the other will receive a sham (placebo) stimulation that feels similar but has no therapeutic effect. The treatment will be given three times a day for seven consecutive days.

Before and after the treatment period, all participants will complete clinical questionnaires to measure their anxiety and related symptoms. They will also undergo Magnetic Resonance Imaging (MRI) scans to help researchers understand how cTBS affects brain activity. A follow-up assessment will be conducted two weeks after the treatment ends to check on symptoms.

Eligibility

Primary outcome measure(s)

• Change from Baseline in Hamilton Anxiety Rating Scale (HAMA) Score — Baseline (Day 1), Post-intervention (Day 9), and a 2-week follow-up.
  The HAMA is a 14-item, clinician-administered scale used to assess the severity of anxiety symptoms. Total scores range from 0 to 56, with higher scores indicating more severe anxiety. The change in total score from baseline to post-intervention will be
• Change from Baseline in Self-Rating Anxiety Scale (SAS) Score — Baseline (Day 1), Post-intervention (Day 9), and a 2-week follow-up.
  The SAS is a 20-item self-report scale designed to measure the severity of anxiety symptoms. The standard score ranges from 25 to 100, where higher scores indicate more severe levels of anxiety. The change in standard score from baseline will be assessed.
• Change from Baseline in Resting-State Neural Activity — Baseline (Day 1) and Post-intervention (Day 9).
  Changes in resting-state brain activity will be measured by functional magnetic resonance imaging (fMRI). Analyses will examine neural activity and network dynamics related to the stimulation target (left auditory cortex) and brain circuits implicated in anxiety.

Trial sites (2)

Other trials for the same condition