Ideal Reference for asymmetric cap

Hello all,

In my experiment, I must use a cap that is missing several (7 of 64) electrodes on the left side of the head (in order to apply ultrasound through the left temporal bone).

What is the ideal reference in this situation? Is average reference fine or will I be inappropriately biased towards one side of the head? Though, perhaps this is alright as my electrodes are indeed on that side of the head. What about dual mastoid reference instead?

-Josh

Hi Josh. I’d go for average mastoids for exactly the reason you mention. It’d be a different story if the 7 missing electrodes were randomly scattered around the cap.