Sherlock is being annoying. A 221B fic just because I've never written one!

"Sherlock."

"What?"

"You know what. Stop it."

"Why?"

"It's annoying. I'm trying to write a blog post and that noise is… distracting."

"Mastication arousal is the word you are looking for."

"What?"

"Don't make me repeat myself, you know I hate that."

"But… what kind of arousal?"

"Chewing gum. It's nearly as good for brain work as a nicotine patch, and I'm already wearing three of those."

"Three?"

"Don't you repeat me either, I hate that as well."

"Well then, take off two of the nicotine patches and stop it with the chewing gum…"

"Mastication arousal."

"Don't keep saying that! It sounds… indecent."

"It isn't. Perfectly well documented scientific fact. Chewing gum increases brain stimulation by 32 per cent for twenty minutes afterwards."

"It's probably just the sugar hit. Why can't you drink coffee with sugar in it like you usually do?"

"It's sugar free gum. Besides, you always tell me I put too much sugar in my coffee."

"At least drinking coffee is quiet!"

"…"

"Stop it. You're being annoying."

"If you chewed gum with me…

"Don't say we could have mastication arousal together."

"No, I was going to say the noise wouldn't bother you!"

"Oh."

"And you would be less bothered by distractions."

"Such as you chewing gum."

"Yes, and also…

"Oh God, what now?"

"By me blowing bubbles…"

It is a true fact (or at least a factoid) that Sherlock quotes here - chewing gum does increase concentration and reduce distraction for about 20 minutes afterwards (and it really is called mastication induced arousal!). I'm not sure about the 32 per cent figure, I think he just pulled that number out of the air!