yes, i think that is part of the reason it increases alertness.

it also happens to seal up the mouth and causes you to nose-breathe more fully. so that might even be why it has this effect.

but what is interesting to me now i'm thinking about this, is because this creates some kind of involuntary tendency to breathe better, and i already knew that breathing could change your consciousness. thousands of years of yoga has proven this, but the thing of deliberately forcing yourself to do it, by mewing... this is new to me.