In Vitro Study of Artifact-Recovery Using a 32-Channel Neuromodulator Platform

Stimulation waveforms and artifacts can exceed the neural signal of interest by several orders of magnitude, thus requiring blanking switches to avoid saturation of the front-end and extensive subsequent recorder blind-time during the recovery. Several recent publications propose to instead utilize recording front-ends with high dynamic range, however typically at the cost of reduced first-stage gain and an adversely affected noise efficiency factor. Recently, we have demonstrated a combination of blanking switches and a tuning mechanism for the pseudo-resistor based high-pass corner frequency in a recorder to achieve rapid artifact recovery by temporarily increased settling speed. In this article, we extent this by an in-depth analysis and significantly improve the artifact recovery abilities by utilizing a combination of passive electrode discharge and recorder reset, thereby improving the recovery time after stimulation significantly, to less than
$\mathrm {10~\text {m} \text {s} }$
in spike recordings with maximum gain setting of
$\mathrm {70~\text {dB}}$
. The measurements are conducted with a new hardware platform, and extensive in-vitro verification is provided to demonstrate the feasibility of the combined artifact recovery.