multivariate mediation analysis for EEG signals

[sqy1225]

Hi everyone,

I want to conduct a mediation analysis for EEG data, and the X variable would be conditions, Y would be reaction times, and Mediator would be amplitudes in each electrodes. But here comes the problem: since there are more than 50 electrodes (i.e. more than 50 mediators) and only 1 X and Y variable, how can I conduct this mediation analysis?
Here's my tentative solution, but I am not sure whether it is possible: Can I conduct mediation analysis for each electrodes, and select those electrodes that have significant mediation effect?

I would really appreciate it if anyone could help me.

[ChVerdonk]

I would be very interested in getting the answer that experts in the use of the MediationToolbox might provide to the question above (from sqy1225)!