we are using a Cedrus RB-530 response pad while recording EEG with an EGI sensor net in a reaction time task.
We have noticed that every time the subject presses a button of the pad an artifact (around 6 mV) appears in the EEG signal. We know that it is not elicited by finger movement.
Anybody has noticed anything similar in the EEG recording?
What can we do to avoid these kind of artifacts?
Thanks a lot!