Something horrible happened just now: I gulped from my water bottle, only to have my mouth flooded with room-temperature coffee, and naturally, my gag reflex activated to the fifth degree. Now, sure, the coffee was a bit unpleasant because it had been stewing for several hours, but there are certainly far worse things to accidentally get fired into your mouth hole than lukewarm coffee. What made it so hideous in this instance was the simple fact that I had been expecting water.
Everyone experiences this kind of thing from time to time, when our system is shocked and thoroughly disgusted by an unexpected — albeit ordinarily agreeable — taste or texture. But why the repulsive reaction? What happens in our mouths and brains that results in the oral equivalent of a panic attack?
Evolution, as it often does, might have an answer. “The reason it’s so shocking for people to discover something they’ve tasted is vastly different than they’d expected is because our neurological food-seeking and pleasure apparatus is set up to find predictable, reliable sources of nutrition and calories,” explains psychologist Glenn Livingston, author of Never Binge Again. “If you think of it, from an evolutionary perspective, predictability and reliability would’ve been a strong survival advantage — when food was scarce, being able to recognize and predict where it would appear, as well as the rewarding sensations that accompanied it’s ingestion, would have been necessary to cement neurological grooves so it could be easily found again.”
Likewise, having an active radar for any foodstuff that strayed from the norm could have helped prevent our early ancestors from consuming anything toxic. “Taking sharp notice of unexpected variations once a neurological pathway had been myelinated would have stimulated us to pay attention and more thoroughly study the situation, such that we could restore our ability to reliably predict nutrition and calorie sources in the future,” Livingston says. “The unexpected taste could represent a better opportunity to reliably source nutrition and calories, or it could represent a poisonous danger. Either way would require closer attention and study.”
“In plain English,” Livingston continues, “we’re set up to ‘wake up’ when we taste something we weren’t expecting, because it represents a potent opportunity to gain a survival advantage via a better food supply, and because if we unexpectedly ingest poison, we could die.”
Well, that certainly adds some perspective to my coffee-soaked keyboard.
Evolution aside, humans are also hardwired to have expectations and to be shaken when those expectations fall through. “Habits cause us to expect things to be as we remember,” says psychologist Maria Baratta, author of Skinny Revisited: Rethinking Anorexia Nervosa and Its Treatment. “Humans are in the habit of eating foods they like, so those expectations compounded with the icky or unexpected will elicit a negative response. The brain is prepared to experience one thing, and another thing took its place.” That explains, in these instances, why the actual taste or texture often matters a lot less than the fact that you were surprised by it.
Similarly, when we expect (and possibly even crave) one thing, nothing else quite hits the spot. “Say you’re in the mood for seafood, and you settle on frozen yogurt instead,” Baratta explains. “You may like frozen yogurt, but you’re not going to enjoy it, at least not at that meal.”
All of which is to say, yeah, I would have preferred not to spew coffee all over my desk this morning. But I guess I can at least rest easy knowing my body would instinctively do the same had I accidentally glugged a glass of Windex instead.