I'm relatively new to guitar effects, I'm just trying to figure out what this one specific effect is. The only way I can describe it would be it's essentially a noise gate that opens while you play a note. It's a pretty common effect used by Umphrey's Mcgee and specifically Brendan Bayliss. In this video at 9:45 you get the best example I can find of it. Can anyone tell me what it is? Sounds like reverse delay almost but I'm not sure and can't seem to find information.

https://www.youtube.com/watch?v=KhXCcmHyArk (9:45)