Focused ultrasound modifications of neural circuit activity in a mammalian brain

Ultrasound Med Biol. 1998 May;24(4):557-65. doi: 10.1016/s0301-5629(98)00014-3.


The application of focused, pulsed ultrasound was studied as a method of modifying the activity of a local neural circuit of the mammalian brain. An in vitro hippocampal preparation was used to facilitate delivery, dosimetry and assessment of mechanisms of ultrasound effects. Extracellular evoked potentials were recorded from cell and dendritic layers of the rat hippocampal dentate gyrus. Focused pulses of ultrasound with center frequency of 500 kHz and repetition rate of 200 kHz were studied and found both to enhance and to depress electrically evoked field potentials. The fiber volley and cell population potentials were depressed, whereas the dendritic potential was enhanced. Results suggest a simultaneous mechanical and thermal mechanism of ultrasound in modifying evoked field potentials of dentate local circuits.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dentate Gyrus / physiology*
  • Evoked Potentials*
  • In Vitro Techniques
  • Male
  • Pulsatile Flow
  • Rats
  • Rats, Sprague-Dawley
  • Reaction Time
  • Temperature
  • Transducers
  • Ultrasonics*