Washington D.C. [USA], May 7 : Here's an interesting piece of information for all the Pokenerd out there. Recent findings have identified preferential activation to Pokemon characters in the brains of people who played Pokemon videogames extensively as kids.
A recent study suggests that if your childhood involved countless hours spent capturing, training and battling Pokemon via video games, there may be a part of your brain that is fond of images of Wobbuffet, Bulbasaur and Pikachu.
The findings, published online in the journal Nature Human Behavior, help shed light on two related mysteries about our visual system. "It's been an open question in the field why we have brain regions that respond to words and faces but not to, say, cars. It's also been a mystery why they appear in the same place in everyone's brain," said study first author Jesse Gomez.
A partial answer comes from recent studies in monkeys at Harvard Medical School. Researchers there found that in order for regions dedicated to a new category of objects to develop in the visual cortex -- the part of the brain that processes what we see -- then exposure to those objects must start young when the brain is particularly malleable and sensitive to the visual experience.
While wondering if there was a way to test whether this was also true in humans, Gomez recalled his own childhood and the countless hours he spent playing videogames, and one game in particular: Pokemon Red and Blue.
"I played it nonstop starting around age 6 or 7," Gomez said. "I kept playing throughout my childhood as Nintendo kept coming out with new versions."
Gomez reasoned that if early childhood exposure is critical for developing dedicated brain regions, then his brain -- and those of other adults who played Pokemon as kids -- should respond more to Pokemon characters than other kinds of stimuli.
And since the Pokemon characters from the games look very different from objects we typically encounter in our daily experience, visual theories make unique predictions about where activations to Pokemon should appear.
The more they considered this concept, the more they realised they had all of the ingredients of a really good natural experiment on their hands.
The first Pokemon game was released in 1996 and played by children as young as 5 years old, many of whom continued to play later versions of the game well into their teens and even early adulthood.
The games not only exposed these children to the same characters over and over again but also rewarded them when they won a Pokemon battle or added a new character to the in-game encyclopedia called the Pokedex.
Furthermore, every child played the games on the same handheld device -- the Nintendo Game Boy -- which had the same small square screen and required them to hold the devices at roughly the same arm's length.
This last point, the Stanford researchers realised, could be used to test a visual theory called eccentricity bias, which states that the size and location of a dedicated category region in the brain depends on two things: how much of our visual field the objects take up, and also which parts of our vision - central or peripheral - we use to view them.
Playing Pokemon on a tiny screen means that the Pokemon characters only take up a very small part of the player's centre of the view. The eccentricity bias theory thus predicts that preferential brain activations for Pokemon should be found in the part of the visual cortex that processes objects in our central, or foveal, vision.
As part of the study, researchers recruited adults who had played Pokemon extensively as children.
When the test subjects were placed inside a functional MRI scanner and shown hundreds of random Pokemon characters, their brains responded more to the images compared to a control group who had not played the videogame as children.
"I initially used the Pokemon characters from the Game Boy game in the main study, but later I also used characters from the cartoon in a few subjects. Even though the cartoon characters were less pixelated, they still activated the brain region," Gomez explained.
The site of the brain activations for Pokemon was also consistent across individuals. It was located in the same anatomical structure -- a brain fold located just behind our ears called the occipitotemporal sulcus. As best the researchers can tell, this region typically responds to images of animals (which Pokemon characters resemble).
According to researchers, the new findings are just the latest evidence that our brains are capable of changing in response to experiential learning from a very early age, but that there are underlying constraints hardwired into the brain that shape and guide how those changes unfold.