Efficacy and Safety of Transcranial Temporal Interference Stimulation for Depression

Major depressive disorder (MDD) is a common and disabling mental disorder. Although medication, psychotherapy, and established brain stimulation methods can help many people with MDD, some participants still have insufficient improvement. Transcranial temporal interference stimulation (tTIS) is a non-invasive brain stimulation technique that may allow modulation of deeper brain regions or pathways. This study is designed to evaluate whether tTIS can improve depressive symptoms in adults with MDD, assess its safety, and explore potential neuroimaging mechanisms. This is a single-center, randomized, double-blind, sham-controlled clinical trial conducted at Zhongda Hospital, Southeast University. Eligible participants with MDD will be randomly assigned in a 1:1:1 ratio to one of three groups: active tTIS targeting the left anterior limb of the internal capsule (ALIC), active tTIS targeting the left subgenual anterior cingulate cortex (sgACC), or sham tTIS. The sham stimulation will be designed to provide sensory feedback similar to active stimulation while maintaining blinding. Participants with MDD will receive 10 treatment sessions over 5 consecutive days, with two 20-minute sessions each day. Clinical symptoms and safety will be assessed at baseline, after treatment, and during follow-up. The main clinical outcome is the change in the 24-item Hamilton Depression Rating Scale (HAMD-24) total score from baseline to after treatment. Secondary outcomes include follow-up changes in depressive symptoms, response and remission rates, anxiety symptoms, anhedonia, psychosomatic symptoms, side effects, and adverse events. Multimodal 5.0T brain magnetic resonance imaging (MRI) will be collected from participants with MDD before and after treatment. MRI measures will include structural imaging, resting-state functional imaging, and diffusion imaging. These data will be used to explore changes in brain structure, functional connectivity, and diffusion-related measures after tTIS, and to identify potential imaging biomarkers related to treatment response.