Characteristics of electrode impedance and stimulation efficacy of a chronic cortical implant using novel annulus electrodes in rat motor cortex

Wang, Chun; Brunton, Emma; Haghgooie, Saman; Cassells, Kahli; Lowery, Arthur J.; Rajan, Ramesh

doi:10.1088/1741-2560/10/4/046010

Cited by 35 publications

(37 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These electrodes were observed to have an impedance of less than 1 kΩ at 1 kHz in saline, and could therefore be identified and re-insulated prior to implantation. Following implantation, electrode impedances at 1 kHz were observed to increase two-fold, which is consistent with prior observations [47]. While 1 kHz impedance is a commonly used measure for electrode viability, we did not observe any significant in vivo impedance changes between functional electrodes and those that were identified, though x-ray, to have fractured wires at this frequency.…”

Section: Discussionsupporting

confidence: 90%

Chronic impedance spectroscopy of an endovascular stent-electrode array

et al. 2016

View full text Add to dashboard Cite

show abstract

Section: Discussionsupporting

confidence: 90%

Chronic impedance spectroscopy of an endovascular stent-electrode array

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Likewise, current clinical deep brain stimulation (DBS) implants could benefit tremendously from improved electrode technology. The DBS electrode surface impedance increases rapidly following implantation due to scar tissue encapsulation [28–30]. This decreases the effective range of the DBS electrode, increases battery drainage and causes variation in therapeutic effects [31].…”

Section: Introductionmentioning

confidence: 99%

Ultrasoft microwire neural electrodes improve chronic tissue integration

et al. 2017

View full text Add to dashboard Cite

Chronically implanted neural multi-electrode arrays (MEA) are an essential technology for recording electrical signals from neurons and/or modulating neural activity through stimulation. However, current MEAs, regardless of the type, elicit an inflammatory response that ultimately leads to device failure. Traditionally, rigid materials like tungsten and silicon have been employed to interface with the relatively soft neural tissue. The large stiffness mismatch is thought to exacerbate the inflammatory response. In order to minimize the disparity between the device and the brain, we fabricated novel ultrasoft electrodes consisting of elastomers and conducting polymers with mechanical properties much more similar to those of brain tissue than previous neural implants. In this study, these ultrasoft microelectrodes were inserted and released using a stainless steel shuttle with polyethyleneglycol (PEG) glue. The implanted microwires showed functionality in acute neural stimulation. When implanted for 1 or 8 weeks, the novel soft implants demonstrated significantly reduced inflammatory tissue response at week 8 compared to tungsten wires of similar dimension and surface chemistry. Furthermore, a higher degree of cell body distortion was found next to the tungsten implants compared to the polymer implants. Our results support the use of these novel ultrasoft electrodes for long term neural implants.

show abstract

“…This stabilization of the electrochemical properties around week 3-4 is likely related to stabilization of the electrode-tissue interface [6]. The continued increase of the electrode impedance at 0.1 Hz for both smooth and porous electrodes coincides with [9], where increasing impedance magnitudes at 1 kHz were found during the first 6 weeks of implantation [9].…”

Section: Discussionmentioning

confidence: 77%

Comparison of the electrochemical properties of smooth and porous TiN electrode coatings in rats

Meijs

Sørensen

et al. 2015

2015 7th International IEEE/EMBS Conference on Neural Engineering (NER)

View full text Add to dashboard Cite

Eight smooth and 8 porous titanium nitride (TiN) coated electrodes were implanted in 8 rats. Before implantation, voltage transients (VTs), cyclic voltammograms (CVs) and impedance spectra were recorded in phosphate buffered saline (PBS). During the implanted period, these measurements were repeated weekly. The VTs and CVs at high sweep rates of the porous electrodes were more affected by implantation as compared to the smooth electrodes. The charge injection (Q inj ) and charge storage capacity (CSC) of both electrode types decreased during the first 3 weeks after implantation. This indicates that protein adhesion directly after implantation presents a diffusion limitation for the porous electrodes only, while cell adhesion limits diffusion for both smooth and porous electrodes.

show abstract

Characteristics of electrode impedance and stimulation efficacy of a chronic cortical implant using novel annulus electrodes in rat motor cortex

Abstract: The present results provide support for the use of annulus electrodes in future applications in cortical neural prostheses.

Cited by 35 publications

References 60 publications

Chronic impedance spectroscopy of an endovascular stent-electrode array

Chronic impedance spectroscopy of an endovascular stent-electrode array

Ultrasoft microwire neural electrodes improve chronic tissue integration

Comparison of the electrochemical properties of smooth and porous TiN electrode coatings in rats

Contact Info

Product

Resources

About