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Voltage biasing, cyclic voltammetry, & electrical impedance spectroscopy for neural interfaces.

Wilks SJ, Richner TJ, Brodnick SK, Kipke DR, Williams JC, Otto KJ - J Vis Exp (2012)

Bottom Line: As implanted electrodes age, EIS and CV data change, and electrode sites that previously recorded spiking neurons often exhibit significantly lower efficacy for neural recording.Typically, EIS is measured daily as an indication of the tissue response at the electrode site.CV and EIS are then repeated to check the changes at the electrode-tissue interface, and neural recordings are collected.

View Article: PubMed Central - PubMed

Affiliation: Weldon School of Biomedical Engineering, Purdue University, USA.

ABSTRACT
Electrical impedance spectroscopy (EIS) and cyclic voltammetry (CV) measure properties of the electrode-tissue interface without additional invasive procedures, and can be used to monitor electrode performance over the long term. EIS measures electrical impedance at multiple frequencies, and increases in impedance indicate increased glial scar formation around the device, while cyclic voltammetry measures the charge carrying capacity of the electrode, and indicates how charge is transferred at different voltage levels. As implanted electrodes age, EIS and CV data change, and electrode sites that previously recorded spiking neurons often exhibit significantly lower efficacy for neural recording. The application of a brief voltage pulse to implanted electrode arrays, known as rejuvenation, can bring back spiking activity on otherwise silent electrode sites for a period of time. Rejuvenation alters EIS and CV, and can be monitored by these complementary methods. Typically, EIS is measured daily as an indication of the tissue response at the electrode site. If spikes are absent in a channel that previously had spikes, then CV is used to determine the charge carrying capacity of the electrode site, and rejuvenation can be applied to improve the interface efficacy. CV and EIS are then repeated to check the changes at the electrode-tissue interface, and neural recordings are collected. The overall goal of rejuvenation is to extend the functional lifetime of implanted arrays.

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Voltage biasing, cyclic voltammetry, & electrical impedance spectroscopy for neural interfaces.

Wilks SJ, Richner TJ, Brodnick SK, Kipke DR, Williams JC, Otto KJ - J Vis Exp (2012)

© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3376927&req=5

Bottom Line: As implanted electrodes age, EIS and CV data change, and electrode sites that previously recorded spiking neurons often exhibit significantly lower efficacy for neural recording.Typically, EIS is measured daily as an indication of the tissue response at the electrode site.CV and EIS are then repeated to check the changes at the electrode-tissue interface, and neural recordings are collected.

View Article: PubMed Central - PubMed

Affiliation: Weldon School of Biomedical Engineering, Purdue University, USA.

ABSTRACT
Electrical impedance spectroscopy (EIS) and cyclic voltammetry (CV) measure properties of the electrode-tissue interface without additional invasive procedures, and can be used to monitor electrode performance over the long term. EIS measures electrical impedance at multiple frequencies, and increases in impedance indicate increased glial scar formation around the device, while cyclic voltammetry measures the charge carrying capacity of the electrode, and indicates how charge is transferred at different voltage levels. As implanted electrodes age, EIS and CV data change, and electrode sites that previously recorded spiking neurons often exhibit significantly lower efficacy for neural recording. The application of a brief voltage pulse to implanted electrode arrays, known as rejuvenation, can bring back spiking activity on otherwise silent electrode sites for a period of time. Rejuvenation alters EIS and CV, and can be monitored by these complementary methods. Typically, EIS is measured daily as an indication of the tissue response at the electrode site. If spikes are absent in a channel that previously had spikes, then CV is used to determine the charge carrying capacity of the electrode site, and rejuvenation can be applied to improve the interface efficacy. CV and EIS are then repeated to check the changes at the electrode-tissue interface, and neural recordings are collected. The overall goal of rejuvenation is to extend the functional lifetime of implanted arrays.

Show MeSH
Related in: MedlinePlus