Charge Density and Charge Per Phase as Cofactors in Neural Injury Induced by Electrical Stimulation

  • Mccreery D
  • Agnew W
  • Yuen T
 et al. 
  • 1

    Readers

    Mendeley users who have this article in their library.
  • N/A

    Citations

    Citations of this article.

Abstract

The possiblility of neural injury during prolonged electrical stimulation of the brain imposes some constraints on the use of this technique for therapeutic and experimental applications. Stimulating electrodes of various sizes were used to investigate the interactions of two stimulus parameters, charge density and charge per phase, in de-terming the threshold of neural injury induced by electrical stimulation. Platinum electrodes ranging in size from 0.002 to 0.5 Em2 were implanted over the parietal cortex of adult cats. Penetrating micro-electrodes fabricated from iridium, with surface areas of 65 f 3 x cm2 were inserted into the parietal cortex. Ten days after implan-tation, the electrodes were pulsed continuously for 7h using charge balanced , current regulated, symmetric pulse pairs, 400 ps per phase in duration, at a repetition rate of 50 Hz. The animals were perfused immediately after the stimulation for histologic evaluation of the brain tissue subjacent to the electrode sites. The results show that charge density (as measured at the surface of the stimulating electrode), and charge per phase, interact in a synergistic manner to determine the threshold of stimulation-induced neural injury. This interaction occurs over a wide range of both parameters; for charge density from at least 10 to 800 pC/cm2 and, for charge per phase, from at least 0.05 to 5.0 pC per phase. The significance of these findings in elucidating the mechanisms underlying stimulation-induced injury is discussed.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

There are no full text links

Authors

  • Douglas B Mccreery

  • William F Agnew

  • Ted G H Yuen

  • Leo Bullara

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free