With all the hormones and whatnot inside. Dopamine, adrenaline, melatonin, whatever. Also, there’s this Hunter S. Thompson bit on the… pineal gland?
If it had an effect on you, wouldn’t it be a really messed up high, all over the place? With uppers, downers etc mixed? (Not including the emotional implications of eating raw human brains.)
It resembles mad cow disease because they’re both prion diseases, which are more or less only spread by consumption of brain.
Some of the other nasty ones that keep my a little freaked out are Chronic wasting disease, aka the zombie deer disease and Fatal Insomnia , which just sounds like something straight from a horror film.