Dear Alfonso,

I imported Power264 atlas and divided the brain into 264 ROIs. For the first-level analysis, I obtained a 264*264 matrix for each participant. However, for several participants, dark lines could be observed in the connectivity matrix and values for these ROIs are all zero (please check the link https://imgur.com/a/JfqUarm). However, there is no any error if I imported AAL90 atlas. Could you kindly give me some suggestions? Thank you so much!

Best,
Gucy