If you want to model a 16-second hemodynamic response with a TR of 2 seconds, TENT(0,16,9) is an appropriate choice.
To compare the average response profile (rather than the area under the curve) between the first and second sessions across two conditions (e.g., cse and csm), you can use the following symbolic notation:
-gltsym 'SYM: cse1[[0..8]] +csm1[[0..8]] -cse2[[0..8]] -csm2[[0..8]]'
This approach tests for differences in the overall shape of the response. For expanding this to a group-level analysis, please refer to this blog post for a detailed walkthrough on profile estimation.
Gang Chen