title: Targeted, noninvasive blockade of cortical neuronal activity.
abstract: Here we describe a novel method to noninvasively modulate targeted brain areas through the temporary disruption of the blood-brain barrier (BBB) via focused ultrasound, enabling focal delivery of a neuroactive substance. Ultrasound was used to locally disrupt the BBB in rat somatosensory cortex, and intravenous administration of GABA then produced a dose-dependent suppression of somatosensory-evoked potentials in response to electrical stimulation of the sciatic nerve. No suppression was observed 1-5 days afterwards or in control animals where the BBB was not disrupted. This method has several advantages over existing techniques: it is noninvasive; it is repeatable via additional GABA injections; multiple brain regions can be affected simultaneously; suppression magnitude can be titrated by GABA dose; and the method can be used with freely behaving subjects. We anticipate that the application of neuroactive substances in this way will be a useful tool for noninvasively mapping brain function, and potentially for surgical planning or novel therapies.
authors.affiliation: Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Nathan
authors.initials: N
authors.lastname: McDannold
authors.affiliation: Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Yongzhi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Chanikarn
authors.initials: C
authors.lastname: Power
authors.affiliation: Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Costas D
authors.initials: CD
authors.lastname: Arvanitis
authors.affiliation: Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Natalia
authors.initials: N
authors.lastname: Vykhodtseva
authors.affiliation: Department of Neurobiology, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Margaret
authors.initials: M
authors.lastname: Livingstone
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier; D002540:Cerebral Cortex / Q000166:cytology / Q000502:physiology*; D004558:Electric Stimulation; D005073:Evoked Potentials, Somatosensory; D008279:Magnetic Resonance Imaging; D008297:Male; D009474:Neurons / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D005680:gamma-Aminobutyric Acid / Q000008:administration & dosage
chemical_list: D005680:gamma-Aminobutyric Acid