Transcranial Ultrasound Stimulation (TUS)

Focused Ultrasound Stimulation (FUS) is a non-invasive neuromodulation technique that uses ultrasound waves to interact with brain tissue. Ultrasound can reach deep and well-defined brain regions without the need for surgery.

Different types of ultrasound are used in neuroscience and clinical practice. High-intensity focused ultrasound (HIFU) is used for thermal ablation, for example in the treatment of movement disorders. In contrast, low-intensity focused ultrasound (LIFU), also called Transcranial Ultrasound Stimulation (TUS) can temporarily modulate brain activity, making it a promising tool for research and potential therapeutic applications. Intermediate intensities can be used to transiently open the Blood Brain barrier (BBB).

In our research at 4BRAIN, we mostly focus on TUS. The stimulation is delivered through a transducer placed on the scalp, which emits ultrasound waves that are directed toward a specific brain region. Using structural imaging such as MRI and CT, we can precisely target areas of interest in an individualized way.

Although the exact mechanisms are still being investigated, ultrasound is thought to influence neuronal activity through mechanical effects on brain cells via mechanosensitive and voltage-gated ion channels. This can lead to temporary changes in brain excitability, which can be measured using electrophysiological techniques.

Transcranial ultrasound is currently being explored in a range of neurological and psychiatric conditions, including epilepsy. Its ability to non-invasively and focally modulate brain activity makes it a promising addition to existing non-invasive neuromodulation techniques.