Transcranial ultrasound stimulation of the subthalamic nucleus modulates cognitive function in humans

Transcranial ultrasound stimulation (TUS) is an emerging neuromodulation technique that can target subcortical structures with high precision. Previous research has reported basic behavioural changes with TUS; however, the capacity of TUS to modulate higher-order cognitive functions requires further investigation. Here, we examined whether TUS applied to the subthalamic nucleus (STN) could alter cognitive and motor function in healthy adults. 28 participants underwent TUS or sham stimulation (unifocal N = 18; multifocal N = 10) in a randomized double-blind fashion on separate testing days. A 128-element transducer was used, operating at 250 kHz with a sonication duration of 120 s (unifocal) or 30 s at each of 7 regions (multifocal), 10% duty cycle, 100 Hz PRF, I SPPA = 10 W/cm 2 , and I SPTA = 1 W/cm 2 . Cognitive effects were assessed using the Stroop task, a measure of response inhibition, whereas motor effects were assessed using a finger-tapping task. The Stroop effect significantly decreased following TUS application to the STN (TUS: 43.87 (±37.03) ms; sham: 54.55 (±40.32) ms; p = .05) and was more pronounced following multifocal stimulation ( p = .047). This study highlights the ability of TUS to alter response inhibition when targeting the STN and validates TUS’s ability to modulate subcortical structures.