[Eeglablist] The effect of gradual change of electrode impediance on EEG data

[周云晖]

Dear all,


I am recently considering an EEG experiment to study the effect of training for a certain task on EEG data. The experiment won't be long, 1-2 hours max, and the naive participants will learn to perform a task with (hopefully) an increasing correct response rate. We hope to study the how EEG data gradually change during the training process. Our candidate EEG features are ERP waves, power of some frequency bands, and metrics of function connectivity.


We note that the impedance of electrodes may gradually change during an experiment session, and we don't want this to confound the possible training effect. Before experiment, we will make sure every the impedance of every electrodes fall below 10k Ohm, and we won't take off the cap or reapply the gel during the experiment. How will such gradual impedance drift change the ERP waveform or power of frequency bands? Are there any published paper talking about this issue?



I know this question has been discussed before (https://sccn.ucsd.edu/pipermail/eeglablist/2014/007380.html), but I think I need more information here. The device we use is BrainProduct ActiChamp with 64 active electrodes.


Best,


Zhou