Hi all,

i was doing a post vs pre contrast by averaging all the conditions and contrasting 3 (post 1, post2, pre2)of them vs 1 (pre1), as below. did i set correctly the contrast? should i balance or it is automaticcally balanced?? i have almost finished the project but and i got this doubt this doubt :-(.

Second question, how to weight the post sessions? i want to see connectivity changes over time

thank you a lot

I believe the contrast you want is

1/3 1/3 -1 1/3

So the contrast vector adds to zero. Each of post1, post2 and pre2 contribute a third to the positive part of the contrast, versus pre1, which contributes fully to the negative part of the contrast.

But I'm not entirely sure about this, so hopefully someone else will chime in here.

Chris