Often in people who have this disorder, they experience loss of muscle tone which presents similarly to fainting after experiencing emotion (anger, excitement, surprise, laughter).
In my case, I thought I was having
fainting spells, but was actually experiencing Cataplexy, which is when your body actually abruptly enters a REM sleep cycle. Since we are paralyzed while we are in REM sleep cycles, it results in a sudden loss of muscle tone or fainting.