From the SRD:
Each round the target suffers excruciating pain and takes 2d6 points of nonlethal damage, 1 point of Dexterity damage, and 1 point of Constitution damage, and its speed is reduced by 10 feet. Once per round as a free action on its turn, the target can attempt a new Fortitude saving throw to resist the spell for 1 round.
My question is, are these effects cumulative? So round 1 the target fails to save and takes 2d6 nonlethal damage, 1pt dex damage, 1pt con damage and speed reduced by 10 feet. On round two does the target take additional nonlethal and ability damage? Is it's movement reduced by 20 feet total now?
Furthermore if the target resists for one round, what happens to the ability damage and speed reduction on the following round? Does it reset to 0, or does it pick up where it left off?