Recovery of early neural spikes from stimulation electrodes using a DC-coupled low gain high resolution data acquisition system.

BACKGROUND

Neural responses to electrical stimulation provide valuable information to probe and study the network function. Especially, recording neural responses from the stimulated site provides improved neural interfacing method. However, it is difficult to measure short-delayed responses at the stimulated electrode due to the saturation of the amplifier after stimulation which is called "stimulus artifact". Despite the advances in handling stimulation artifacts, it is still very challenging to deal with the artifacts if one tries to stimulate and record from the same electrode.

NEW METHOD

In this paper, we developed a system consisting of 24 bit ADC and low gain DC-amplifier which allows us to record the entire responses including saturation-free stimulus artifact and neural responses with excellent resolution.

RESULTS

Our approach showed saturation-free recording after stimulation, which makes it possible to recover neural spike as early as in 2 ms at the stimulating electrode with digital elimination methods.

COMPARISON WITH EXISTING METHODS

With our system we could record neural signals after stimulation that was difficult with high gain and high pass filtered recording system due to amplifier saturation.

CONCLUSIONS

Our new system can enhance interface performance with its higher robustness and with simple system configuration.