Why Your Brain Will Trick You This April Fool's Day

Turns out your brain is predisposed to believe pranks.

ByABC News
April 1, 2015, 11:54 AM

— -- If you got taken in by an April Fool's Day prank don't be embarrassed, it turns out we're hardwired to be gullible.

According to experts, the human brain has evolved to sometimes override our clear sensory perceptions of the world around us meaning sometimes we fall for a good prank.

Dr. Adam Gazzaley, a neuroscientist and professor at the University of California San Francisco Medical School, said humans can override our basic "bottom up" sensory perception of the world with "top down" processing, meaning we can override natural instincts with rationalizations.

Gazzaley explains that this could mean ignoring what's going in the physical world around us because we believe we "know" better than what our sense are telling us.

"It’s based on memories and experiences and that is really a powerful force and an overwhelming force in humans that shape how we view the world," explained Gazzaley, of human perceptions of the world around us.

Gazzaley said one example of "top down" processing overriding our "bottom up" perceptions would be missing a close friend on the street because you're in engrossed in your phone screen. Another clear example is going to see a magic show and trying to figure out how the trick is performed, but being unable to.

"In the whole misdirection thing when [the magician is] showing you their hand, your experience is telling you this is important," said Gazzaley. "But they're doing something with the other hand."

Gazzaley said magicians have told him that intoxicated people are better at figuring out the trick because their "top down" processing is dulled.

"You set up your whole belief system based on memories and goals. It shapes your reality in a way that is not exactly corresponding with more on the surface reality," said Gazzaley. "It could create the type of illusions that magicians thrive on."

Gazzaley said as a result people can easily be taken in by a good April Fool's prank.

"April fool’s jokes ... play off across your belief structure and your view of reality to create something that in other circumstances isn’t that believable," he said.

In addition to the "top down" fake out, there's also scare tactic pranks that humans are hard-wired to respond to, according to experts.

Dr. Tanvir Syed, a neurologist at the University Hospitals Case Medical Center in Cleveland, said that the brain is designed to perceive any threat as real, even if it's a rubber snake.

"The way we process any kind of stimulus is by threat level," said Syed. "The way our nervous system is, we respond to threats very quickly…to prepare us for fight or flight."

That means if someone decides to try and prank you with something that scares you, you're likely not going to be able to remain calm and collected. Syed said your brain would rather react to a threat--even a fake threat--than be injured.

Even if you try to plan ahead and have no reaction to a prank designed to scare you, Syed says you'll likely have a subconscious response to any threat, which is "100 times more powerful" than the conscious mind in terms of brain synapses.