Researchers Use Sound Waves To Activate Neuronal Circuits

(CONNECT) Researchers from the University of Zurich (UZH), the Swiss Federal Institute of Technology in Zurich (ETH) and NYU Langone Health in New York have activated neural circuits in mice for the first time using sound waves projected into holograms. This technique, known as transcranial ultrasound stimulation (TUS), is intended to serve as the basis for novel, non-invasive treatments for neurological diseases, according to a press release. To test the TUS, the researchers positioned a helmet-shaped array of 512 ultrasound transmitters over the head of a mouse, which superimposes sound waves in such a way that geometric patterns, such as triangles or pentagons, ("acoustic holograms") are projected onto the surface of the brain.

When the neurons were activated by the ultrasound, they generated a fluorescent signal, which the researchers recorded with a camera and were thus able to measure the extent to which different brain regions of the mice were activated by the TUS technique. "Our results provide new insights into how transcranial ultrasound stimulation (TUS) activates circuits in a living organism," explains Dr. Shy Shoham, Professor in Neuroscience at NYU Grossman School of Medicine and co-author of the study. "We hope that the techniques and computational models we have developed will help other basic researchers to investigate the mechanisms of different brain circuits. Ultimately, our goal is to translate this work into protocols for transcranial ultrasound stimulation for the treatment of various human diseases, such as mental disorders."

Intense sound waves are already used in Parkinson's therapies to kill neurons in tremor-associated nerve pathways. The sound waves used in the study, which are of lower intensity, only activate neurons for a short time. In the future, the researchers want to test whether ultrasound can also activate deeper neuronal circuits in the brain. Several applications are already in the clinical test phase.

The study, which was first published in the journal "Nature Biomedical Engineering", received funding from the National Institutes of Health and the Swiss National Science Foundation. ce/yes