While reading yesterday's entry in the Baraita blog, I noticed the owner using "this is your brain on trupp [musical reading of Bible passages]" and "this is your brain on Judaism" in her latest post. She also posted a link to a site explaining the "this is your brain on drugs" commercial which inspired her allusions.
Remembering frequent posts on Language Log about "snowclone" phrases, I did a Google search for "this is your brain on X" phrases--and got approximately 31,900 hits. Many of them quoted the original ad directly, or specialized the "X" value to specific drugs:
X= drug name # of hits
Amazingly, some synonymous values of X didn't fare as well as "marijuana/pot" above: despite the high number of "this is your brain on alcohol" hits, substituting "booze" gave only ten, and "liquor" gave only two hits. "Food" seems to be the most common non-drug substance named (with 218 hits).
"God" is apparently the most common non-substance value in "this is your brain on X" phrases (423 hits); "the Internet" scores high as well (288 hits). Using synonyms for the latter, "this is your brain online" scores a whopping 393 hits; "this is your brain on the net" scores only two, however.
Those examples, IMO, prove that "This is your brain on X" has become a bona-fide snowclone which outlived the original commercial. I'll leave you with a random sampling of some of the other non-drug hits for this phrase:
This is your brain on exercise...on Florida...on phones...on public relations...on hype...on reality...on Tetris...on Photoshop...on 'fair and balanced'...on boredom...on rejection...on life.
Any questions? :-)