Focused ultrasound neuromodulation of cortical and subcortical brain structures using 1.9 MHz

Authors

  • Kamimura Hermes A. S.,

    1. Department of Biomedical Engineering, Columbia University, New York, New York 10027 and Department of Physics, FFCLRP, University of São Paulo, Ribeirão Preto, SP 14040-901, Brazil
    Search for more papers by this author
    • a)

      Current Address: Molecular Imaging Research Center, Institut d’Imagerie Biomédicale, Commissariat à l’énergie atomique et aux énergies alternatives (CEA), Fontenay-aux-Roses 92265, France.

  • Wang Shutao,

    1. Department of Biomedical Engineering, Columbia University, New York, New York 10027
    Search for more papers by this author
  • Chen Hong,

    1. Department of Biomedical Engineering, Columbia University, New York, New York 10027
    Search for more papers by this author
  • Wang Qi,

    1. Department of Biomedical Engineering, Columbia University, New York, New York 10027
    Search for more papers by this author
  • Aurup Christian,

    1. Department of Biomedical Engineering, Columbia University, New York, New York 10027
    Search for more papers by this author
  • Acosta Camilo,

    1. Department of Biomedical Engineering, Columbia University, New York, New York 10027
    Search for more papers by this author
  • Carneiro Antonio A. O.,

    1. Department of Physics, FFCLRP, University of São Paulo, Ribeirão Preto, SP 14040-901, Brazil
    Search for more papers by this author
  • Konofagou Elisa E.

    1. Department of Biomedical Engineering, Columbia University, New York, New York 10027 and Department of Radiology, Columbia University, New York, New York 10032
    Search for more papers by this author
    • b)

      Author to whom correspondence should be addressed. Electronic mail: ek2191@columbia.edu; Telephone: 212-342-0863; Fax: 212-342-5773.


Abstract

Purpose

Ultrasound neuromodulation is a promising noninvasive technique for controlling neural activity. Previous small animal studies suffered from low targeting specificity because of the low ultrasound frequencies (<690 kHz) used. In this study, the authors demonstrated the capability of focused ultrasound (FUS) neuromodulation in the megahertz-range to achieve superior targeting specificity in the murine brain as well as demonstrate modulation of both motor and sensory responses.

Methods

FUS sonications were carried out at 1.9 MHz with 50% duty cycle, pulse repetition frequency of 1 kHz, and duration of 1 s. The robustness of the FUS neuromodulation was assessed first in sensorimotor cortex, where elicited motor activities were observed and recorded on videos and electromyography. Deeper brain regions were then targeted where pupillary dilation served as an indicative of successful modulation of subcortical brain structures.

Results

Contralateral and ipsilateral movements of the hind limbs were repeatedly observed when the FUS was targeted at the sensorimotor cortex. Induced trunk and tail movements were also observed at different coordinates inside the sensorimotor cortex. At deeper targeted-structures, FUS induced eyeball movements (superior colliculus) and pupillary dilation (pretectal nucleus, locus coeruleus, and hippocampus). Histological analysis revealed no tissue damage associated with the FUS sonications.

Conclusions

The motor movements and pupillary dilation observed in this study demonstrate the capability of FUS to modulate cortical and subcortical brain structures without inducing any damage. The variety of responses observed here demonstrates the capability of FUS to perform functional brain mapping.

Ancillary