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When you see gigantic cartoon eyes, do they make you feel like you want to run away? Do they give you a tingling feeling on the back of your neck…like something is watching you?

Maybe you don't feel that way, but birds who see these eyes do not like them. They're an example of a supernormal stimulus: something that will cause a bigger and bigger response as it's made more intense, even if it's exaggerated way beyond what you'd encounter in nature. This comes from instincts birds acquired through evolution: if you see this kind of shape, get out of there before you become someone's lunch!

In nature, the eyes are…well…small, and not quite so “googly”-eye-looking. But when you show them on big screens and increase the contrast between parts of the eye, researchers have found that birds will fly away from them, which could be useful for keeping them away from airport runways, for example. It's easy for humans to see these exaggerated stimuli for what they are.

We know those gigantic eyes are just an image, not an actual threat to a bird. But that's because we haven't evolved the same instinctive reaction to it that birds have. Some psychologists argue that there are other superstimuli we might be susceptible to.

But our ability to recognize them makes a big difference. Take TV, for example. Or any form of video entertainment, really.

The orienting response is an instinct that keeps us safe by causing us to pay attention to novel sights and sounds. Back in the day, it would have helped us spot dangerous predators or hunt for food. Certain forms of entertainment are designed to take advantage of that, with constantly changing sights and sounds that trigger your orienting response over and over again.

You know the type — commercials, action sequences, that kind of thing. They capture your attention partly by triggering a super strong orienting response, way more than anything you'd encounter in nature. But overloading your orienting response can actually backfire.

Sure, you're looking at the screen, but in studies, learning and recall tends to drop. Sugar, fat, and salt might be another example of this. In the early days of our species, these were hard to come by, but critical for our survival.

So our brains rewarded us for eating these things, and they still do today. But we can get these concentrated flavors at any time, and in concentrations and combinations that aren't found in nature — like the sweet, fatty, and salty combo of peanut butter. M&M… who even made that thing real?

And our reaction to those more intense concentrations is to want more of them, even if there's so much sugar, fat, and salt in that peanut M&M that it is unhealthy for us to eat. Some researchers have proposed other kinds of supernormal stimuli in humans, like high heels, art, and the internet. All are examples of how humans have modified our environment from what it was thousands of years ago.

On the other hand, many researchers point out that while evolution has led to these exaggerated responses, it's also given us an exceptionally large cerebral cortex. That's the part of your brain you use to make decisions — sometimes decisions against your natural instincts, which is exactly the kind of instincts that supernormal stimuli trigger. So, with this big brain of yours, you can decide to shut off the TV or make sure that you don't buy another giant package of peanut butter M&Ms — ways of avoiding being sucked into an exaggerated response that you don't want to have.

Plus, not all supernormal stimuli are bad. We know that when we go to the movies what we're seeing isn't real, but I still want to watch the new Mission Impossible movie. Many supernormal stimuli, in moderation, are ways we enjoy ourselves.

Finally, it's worth keeping in mind that not everyone reacts to this stuff in the same way. You might be one of those people who doesn't get all hot and bothered by the big bowl of peanut M&Ms, maybe your sibling isn't that into Tom Cruise hanging off the side of an airplane. So, it's not like supernormal stimuli will be humanity's downfall or anything.

But it's an important thing to keep researching, because we will continue to get better at modifying our environment. We're already seeing the negative consequences of unhealthy foods that are so delicious all we want to do is sit around eating them. And pretty soon, we might be faced with virtual reality experiences so engrossing that it wouldn't be much of a surprise if some people preferred them over real life.

There aren't easy answers to these questions. But while our brains might be the problem, they're also the solution. Thanks for watching this episode of SciShow Psych!

And thanks especially to our community on Patreon — this channel exists because of your support. If you're interested in learning more about how you can help us keep exploring the weird quirks of the human brain, just check out patreon.com/scishow. [♪ OUTRO ].