3dDeconvolve

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1

Hello AFNI experts

I am working in an emotional fMRI task. I am interested to see the activations in different contrasts: faces vs shapes, anger vs neutral, fear vs neutral, fear+anger vs neutral.

I have the stats for the faces vs shapes, anger vs neutral, fear vs neutral, which are activation maps generated running 3dDeconvolve (the bucket output).
I made 3dcalc -a file’[39]’ -expr “a*step(a)” -prefix new_file.nii to calculate the voxels greater than 0 considering that Im interested in faces>shapes, anger>neutral, fear>neutral. Please correct me if Im doing something wrong.

Now I want to calculate the anger+fear activation map but I am confused how to average this. Could you please provide me any advices?

Thank you

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I want to calculate the anger+fear activation map but I am confused how to average this

Do you get the average effect between anger and fear at the subject or population level? At the subject level, if you just want to get the effect estimate, do

3dcalc -a anger -b fear -expr “a+b” -prefix …

If you want to get both the average effect and its statistical evidence, you would have to achieve that with -gltsym by running 3dDeconvolve with the option -xrestore