For the millions of adults with major depressive disorder who either fail to respond to antidepressants or cannot tolerate their side effects, the search for effective noninvasive brain stimulation alternatives remains urgent. A rigorously designed trial now provides the first double-blind, sham-controlled evidence on whether transcranial pulse stimulation (TPS) — a relatively new technique using short ultrasonic pulses to modulate neural activity — can meaningfully reduce depressive symptoms.
Conducted at Hong Kong Polytechnic University between mid-2023 and late 2025, this two-arm parallel randomized clinical trial enrolled 80 adults (mean age 35.6 years; 66% female) diagnosed with major depressive disorder and scoring at least 14 on the Hamilton Depression Rating Scale. Participants received either 12 active or sham TPS sessions over four weeks, each delivering 1,000 pulses targeted at the left dorsolateral prefrontal cortex — a region consistently implicated in mood regulation. The primary endpoint was change in Montgomery-Åsberg Depression Rating Scale (MADRS) score, with a reduction of 12 or more points considered clinically substantial. Seventy-four of 80 participants completed the protocol, with only six withdrawals, two from the sham group due to adverse effects.
TPS occupies a meaningful niche in the neuromodulation landscape alongside transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), both of which have accumulated considerably larger evidence bases. Unlike TMS, TPS uses low-intensity focused ultrasound pulses, theoretically enabling deeper and more spatially precise cortical engagement with minimal discomfort. The left dorsolateral prefrontal cortex targeting mirrors the standard TMS protocol for depression, lending biological plausibility. That said, this single-site trial with 80 participants — drawn by convenience sampling rather than strict random recruitment — limits generalizability. The relatively young, educated cohort may not reflect treatment-resistant or older depressive populations. This trial is best characterized as confirmatory of preliminary signals rather than paradigm-shifting; replication across diverse populations and comparison with established TMS protocols will be essential before TPS can be positioned as a clinical alternative.