Acoustoelectric detection of current flow in a neural recording chamber

R. S. Witte, R. Olafsson, M. O'Donnell

Research output: Chapter in Book/Report/Conference proceedingConference contribution

10 Scopus citations

Abstract

Acoustic pressure (P) traveling in a biologic fluid or tissue generates a local change in electrical conductivity. This acoustoelectric interaction (AE) induces a voltage modulation that depends on local current, resistance, and pressure. We explore the AE signal as a way to enhance traditional electrophysiology or surface recording of neural signals. A thin stretch tube mimicking an enlarged axon and an abdominal segment of a fresh lobster nerve cord were used as test structures for AE detection in a tri-compartment neural recording chamber. Stimulating electrodes passed low frequency current through the structures, while a pair of recording electrodes detected the high frequency AE signal. Ultrasound transducers from 0.5 to 7.5 MHz delivered P up to 2 MPa. The differentially-recorded AE signal was captured on a fast data acquisition board and saved for post processing. In the lobster nerve cord, the AE signal was linear between the tested range of current densities of 9 to 86 mA/cm 2 [18 dB/log(J), r2=0.96] and P of 0.5 to 2 MPa [21 dB/log(P), r2=0.96]. In addition, a transverse scan of the structures produced cross-sectional AE images of current flow with remote detection by the recording electrodes. Results were consistent with AE simulations. This study demonstrates that the AE signal can be used to detect and image current flow in a biologic environment with physiologically-relevant current densities and acoustic pressures on par with clinical ultrasound imaging.

Original languageEnglish (US)
Title of host publication2006 IEEE International Ultrasonics Symposium, IUS
Pages5-8
Number of pages4
DOIs
StatePublished - Dec 1 2006
Externally publishedYes
Event2006 IEEE International Ultrasonics Symposium, IUS - Vancouver, BC, Canada
Duration: Oct 3 2006Oct 6 2006

Publication series

NameProceedings - IEEE Ultrasonics Symposium
Volume1
ISSN (Print)1051-0117

Other

Other2006 IEEE International Ultrasonics Symposium, IUS
CountryCanada
CityVancouver, BC
Period10/3/0610/6/06

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ASJC Scopus subject areas

  • Acoustics and Ultrasonics

Cite this

Witte, R. S., Olafsson, R., & O'Donnell, M. (2006). Acoustoelectric detection of current flow in a neural recording chamber. In 2006 IEEE International Ultrasonics Symposium, IUS (pp. 5-8). [4151872] (Proceedings - IEEE Ultrasonics Symposium; Vol. 1). https://doi.org/10.1109/ULTSYM.2006.16