Chumley does this exact same thing...a very long deep breath and exhales it all...then you hear nothing for 5 seconds..its very scaryVery interesting, Kevin.
Stouffer does something like this. I've never noticed it when he's in his REM sleep, though. First he will take a REALLY deep breath, blow it out, and then there is like a 5-7 second pause before he starts breathing again. Not sure if this is normal, but it always makes me a little nervous.