[FieldTrip] Decreased coherence at 60Hz?

[Daria Boratyn]

Hi all,

Using FieldTrip, I created bipolar montages on each hemisphere and then calculated the coherence between those. I am getting an odd result and seeing a decrease in coherence at 60Hz for some of my runs. My understanding is that 60 cycle noise should be picked up by every electrode and would therefore have high coherence values across the board. Would anyone have a suggestions as to what could be causing this? I’ve attached a screenshot of what I’m seeing. 
Thank you,
Daria

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