if I just include this line of code in a model TaskxTimexSexxCravP:

-gltLabel 1 'Male_stress_CravP' -gltCode 1 'Gender : 1*Male Task : 1*stress CravP : ' \

my understanding is that this contrast will show me regions of significant activation during stressful condition that predict craving in males. Of note here, the craving variable varies within cluster (so we have diff craving values for each condition (stress, neutral or drug) and for each subject - I have mean centered within cluster and included crav as a random effect).

if I just include this line of code in a separate model TaskxTimexSexxHDD:

-gltLabel 1 'Male_stress_HDD' -gltCode 1 'Gender : 1*Male Task : 1*stress HDD : ' \

my understanding is that this contrast will show me regions of significant activation during stressful condition that predict binge/heavy drinking days in males.

What I would like to know is if the activation in the regions that appear to predict craving during stress in males (or females) may be stronger among those males (or females) with higher % of binge drinking days (i.e., this relationship between stress and craving in males may vary as a result of heavy drinking days).