Oh, sorry, Gang, I should've explained the analysis a bit more.
This is a longitudinal analysis where the variables are:
1. con_linear (continuous-within) - a contrast of our within-subject functional task. Easy, medium, and hard conditions for each subject were coded as -1, 0, and 1.
2. age_w1 (continuous-between) - their age at wave 1
3. lag_years (continuous-between) - the difference/lag between their wave 1 and wave 2 in years
Thank you,
Ekarin