Senior author Duje Tadin, an assistant professor of brain and cognitive sciences at the University of Rochester, and Michael Melnick, a doctoral candidate in brain and cognitive sciences at the University of Rochester, said the study showed individuals whose brains were better at automatically suppressing background motion performed better on standard measures of intelligence.
Individuals watched brief video clips of black and white bars moving across a computer screen. Their only task was to identify which direction the bars drifted: to the right or to the left. The bars were presented in three sizes, with the smallest version restricted to the central circle where human motion perception is known to be optimal, an area roughly the width of the thumb when the hand is extended. Participants also took a standardized intelligence test.
The study, published online in the journal Current Biology, found people with higher IQ scores were faster at catching the movement of the bars when observing the smallest image.
"Because intelligence is such a broad construct, you can't really track it back to one part of the brain," Tadin said in a statement. "But since this task is so simple and so closely linked to IQ, it may give us clues about what makes a brain more efficient, and, consequently, more intelligent."
A video is at: http://www.youtube.com/watch?v=qxt2Uo_GuXI.