Electrical stimulus artifact cancellation and neural spike detection on large multi-electrode arrays
Fig 3
Properties of the electrical stimulation artifact revealed by TTX experiments.
(A) local, electrode-wise properties of the stimulation artifacts. Overall, magnitude of the artifact increases with stimulation strength (different shades of blue). However, unlike non-stimulating electrodes, where artifacts have a typical shape of a bump around 0.5 ms (fourth column), the case of the stimulating electrode is more complex: besides the apparent increase in artifact strength, the shape itself is not a simple function of stimulating electrode (first and second rows). Also, for a given stimulating electrode the shape of the artifact is a complex function of the stimulation strength, changing smoothly only within certain stimulation ranges: here, responses to the entire stimulation range are divided into three ranges (first, second, and third column) and although traces within each range look alike, traces from different ranges cannot be guessed from other ranges. (B) stimulation artifacts in a neighborhood of the stimulating electrode, at two different stimulus strengths (left and right). Each trace represents the time course of voltage at a certain electrode. Notice that stimulating electrode (blue) and non-stimulating electrodes (light blue) are plotted in different scales.