Image-guided transcranial focused ultrasound stimulates human primary somatosensory cortex.
Focused ultrasound (FUS) has recently been investigated as a new mode of non-invasive brain stimulation, which offers exquisite spatial resolution and depth control. We report on the elicitation of explicit somatosensory sensations as well as accompanying evoked electroencephalographic (EEG) potentials induced by FUS stimulation of the human somatosensory cortex. As guided by individual-specific neuroimage data, FUS was transcranially delivered to the hand somatosensory cortex among healthy volunteers. The sonication elicited transient tactile sensations on the hand area contralateral to the sonicated hemisphere, with anatomical specificity of up to a finger, while EEG recordings revealed the elicitation of sonication-specific evoked potentials. Retrospective numerical simulation of the acoustic propagation through the skull showed that a threshold of acoustic intensity may exist for successful cortical stimulation. The neurological and neuroradiological assessment before and after the sonication, along with strict safety considerations through the individual-specific estimation of effective acoustic intensity in situ and thermal effects, showed promising initial safety profile; however, equal/more rigorous precautionary procedures are advised for future studies. The transient and localized stimulation of the brain using image-guided transcranial FUS may serve as a novel tool for the non-invasive assessment and modification of region-specific brain function.
1] Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon 403-720, Korea [2] School of Nano-Bioscience and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan 689-798, Korea.
Wonhye
W
Lee
1] Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon 403-720, Korea [2] Center for Bionics, Korea Institute of Science and Technology, Seoul 136-791, Korea.
Hyungmin
H
Kim
Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon 403-720, Korea.
Yujin
Y
Jung
Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon 403-720, Korea.
In-Uk
IU
Song
Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon 403-720, Korea.
Yong An
YA
Chung
1] Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon 403-720, Korea [2] School of Nano-Bioscience and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan 689-798, Korea.
Seung-Schik
SS
Yoo
D000161:Acoustic Stimulation; D000328:Adult; D004569:Electroencephalography; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D005385:Fingers / Q000502:physiology; D005500:Follow-Up Studies; D006225:Hand / Q000502:physiology; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D012677:Sensation / Q000502:physiology; D013003:Somatosensory Cortex / Q000000981:diagnostic imaging* / Q000502:physiology*; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods*; D055815:Young Adult