People with high IQ scores aren't just more intelligent. They also process sensory information differently, according to a study reported in the Cell Press journal Current Biology on May 23.
The findings show that the brains of people with high IQ are automatically more selective when it comes to perceiving objects in motion; they are specifically more likely to suppress larger and less relevant background motion.
"It is not that people with high IQ are simply better at visual perception," says Duje Tadin of the University of Rochester. "Instead, their visual perception is more discriminating. They excel at seeing small, moving objects but struggle in perceiving large, background-like motions."
The discovery was made by asking people to watch videos showing moving bars on a computer screen. Their task was to state whether the bars were moving to the left or to the right. The researchers measured how long the video had to run before the individual could correctly perceive the motion. Try it yourself (see videos).
The results show that individuals with high IQ can pick up on the movement of small objects faster than low-IQ individuals can. That wasn't unexpected, Tadin says. The surprise came when tests with larger objects showed just the opposite: individuals with high IQ were slower to see what was right there in front of them.
"There is something about the brains of high-IQ individuals that prevents them from quickly seeing large, background-like motions," Tadin adds. In other words, it isn't a conscious strategy but rather something automatic and fundamentally different about the way their brains work.
That ability to block out distraction could come in very handy in a world filled with more information than we can possibly take in. It helps to explain what makes some brains more efficient than others.
An efficient brain "has to be picky," Tadin says.
Current Biology, Melnick et al.: "A strong interactive link between sensory discriminations and intelligence."