Design for three level analysis

Hi experts,

I have two groups of patients and patients were scanned two times, before and after a training sessions.
Tasks were in the same session included left finger tapping(30s) and right finger tapping(30s) following a rest(30s). I aim to see improvements after training across the two groups. My first level has two regressors, left hand and right hand, and four contrasts, 1. left taps, 2. right taps,3. left>right 4. right > left. I was asked to do three level analysis though, I am having a trouble to design 2nd level and 3rd level analysis for this study. I use feat in FSL to run the analysis.

Any suggestion or similar examples would help me a lot.