Hi Alfonso

Thanks for your reply. Kind of put me in the right track. However, although I am using second level analysis and i am regressing the finding with the lateralization index, I am using just Lateralization index  in Subject Effects, one condition (rest), Between subject Contrast [1] and between condition contrast[ 1](see attached image).  Thanks to your reply I think I understand the the T value gives me the strength to reject the hypothesis of having no relationship between the connectivity of the analyzed ROI and the given lat index.

Thanks a lot and best regards

Magno