New paper: ‘Rapid modulation of choice behavior by ultrasound on the human frontal eye fields‘ - Insights from Soha Farboud

Our recent study in Nature Communications shows that we can bias saccade choices using a novel non-invasive brain stimulation method: transcranial ultrasound stimulation (TUS). This technique uses inaudible sound waves to stimulate the brain from outside the skull, even reaching deep structures without surgery or implants.

Within the Brain Stimulation Lab, we were able to shift perceptual decisions within a fraction of a second by targeting the frontal eye fields. When we began, I wasn’t sure it would work—there was little convincing evidence that TUS was sufficiently effective in humans. Watching the effect consistently emerge over extensive controls was a genuinely exciting moment. The speed of these behaviourally induced changes was particularly striking. We also measured cortical GABA+ with MRS and found substantial individual differences in neurochemistry and behaviour. TUS brought participants to a more comparable, balanced behavioural state.

What excites me most is TUS’s ability to reach deep brain regions. Our recent work stimulating the nucleus accumbens shows promising effects on reinforcement learning, a key system in neuropsychiatric conditions. This opens real opportunities for causal brain mapping and future clinical applications.