Help in understanding effect size in fMRI

[dentons]

Hello everyone, I'm a student of a Master's degree in Neuroscience and I'm preparing a journal club presentation on an article called "Differential extrageniculostriate and amygdala responses to presentation of emotional faces in a cortically blind field". I'm struggling to understand some of the results, in particular what a negative effect size means in fMRI. Is there someone that can explain that to me? I'm referring in particular to this picture of the paper (the one attached).

What can I say about the "unseen CS-"? Why is it so negative? Does it mean that the amygdala has a very low degree of activation?

Thanks to anyone that can help me

[studiot]

Wish I could help but this is beyond me so I take my skull cap off to you.

 

Meanwhile my answer may help keep this thread in sight until those who do understand this stuff are around.

 

and yes, there some of those folks here.

 

[Prometheus]

This paper might help, talks about effect size about half-way through. Otherwise... goodluck.

[dentons]

Thanks to both of you, unfortunately I couldn't find what I needed in that paper :/