Significant Results: Pilot Study on the Effects of TPS in Major Depressive Disorder

Transcranial Pulse Stimulation (TPS) recently investigated for depression

Transcranial Pulse Stimulation (TPS) is the subject of ongoing intensive research. This was recently underlined at an international expert meeting attended by around 50 scientists from 14 countries. This event highlighted the dynamic development in TPS research, thanks to which around 10,000 Alzheimer’s patients have already been treated.

Transcranial Pulse Stimulation is a promising field of research for other neurodegenerative, neurophysiological and psychiatric diseases due to its partially still hypothetical but increasingly better understood mode of action. This applies not only to Alzheimer’s dementia, but also to other indications. Hong Kong Polytechnic University, which has already published independent studies on Alzheimer’s dementia, autism, ADHD and depression in young adults, recently conducted a randomized, controlled, single-blinded pilot study on the efficacy of TPS in the treatment of major depression in adults.

TPS can effectively reduce symptoms in adults with major depression

The primary objective of this study was to investigate the effects of Transcranial Pulse Stimulation (TPS) on the severity of depression in adults in Hong Kong. Secondary objectives included examining the effects of TPS on participants’ anhedonia symptoms, instrumental activities of daily living (IADL) and cognition, and whether there were any changes in functional connectivity in participants’ brains after TPS treatment. In the present work, however, Dr. Cheng and her team chose to focus first on the effects of TPS via psychological instrumental scores. In future publications, the researchers will report on the structural and functional connectivity changes.

The study design complied with the Consolidated Standards of Reporting Trials (CONSORT) statement and good clinical practice guidelines. All subjects underwent appropriate screening procedures to ensure their eligibility. In addition, all subjects underwent a pre-treatment fMRI scan performed at the University Research Facility in Behavioral and Systems Neuroscience at the Hong Kong Polytechnic University, Hong Kong. This ensured that the participants’ brains had no structural defects, tumors, brain trauma or other brain abnormalities.

The researchers, led by Dr. Teris Cheung, included 30 participants in their study. The subjects were randomly assigned to either the TPS group or the waiting list control group (WC), with a 1:1 stratification by gender and age. The primary outcome was assessed using the Hamilton Depression Rating Scale-17 (HDRS-17). The 30 participants recruited were between 18 and 54 years old, predominantly female (73%) and of Chinese descent.

Participants received a two-week TPS treatment with six 30-minute TPS sessions. The primary outcome (i.e., depression) was assessed using the 17-item Hamilton Rating Scale for Depression (HDRS-17) to measure participants’ symptoms of depression and mood. The HDRS-17 is a widely used and reliable method for measuring depressive symptoms and mood. Scores ranged from 0 to 52, with higher scores indicating more severe depression. A clinical response was defined as a reduction in HDRS-17 score of 50 percent or more. An HDRS-17 score of ≤7 was used as an indicator of remission.

Hong Kong study: Large and sustained effects of neurostimulation with TPS

In the present study, the dorsolateral prefrontal cortex (DLPFC) was specifically stimulated to investigate the effects of TPS on depression. There was a significant group x time interaction (F(1, 28) = 18.8, p < 0.001). In addition, a significant reduction in the severity of depressive symptoms was found in the TPS group compared to the WC group (mean difference = -6.60, p = 0.02 and Cohen’s d = -0.93). The results showed a significant intervention effect; moreover, the effect was large and sustained at the three-month follow-up. The study shows that TPS is effective in reducing depressive symptoms in adults with major depression.

Side effects of TPS treatment were rare and marginal: For example, only a few test subjects reported headaches (four percent). None of the test subjects needed to take painkillers for short-term headaches. In addition, only one test subject complained of nausea and vomiting after the first TPS treatment. However, the symptoms subsided within two hours and there were no more such complaints afterwards.

Conclusion: Researchers see TPS as a useful top-on treatment option for depression

Transcranial Pulse Stimulation (TPS) is the latest technological NIBS device that has been shown to be effective, safe and sustainable in reducing major depressive symptoms in adults in this pilot RCT, the authors write. They conclude that TPS may well be considered a top-on treatment option, especially for treatment-resistant patients and those seeking rapid recovery. They suggest further multicenter studies to filter out the placebo effects in a larger sample.


Further studies on Transcranial Pulse Stimulation (TPS) shock wave therapy for various indications in neurology and psychiatry can be found here:

Transcranial Pulse Stimulation (TPS) – Studies