Study of How Brain Corrects Perceptual Errors Has Implications For Brain Injuries
New research provides the first evidence that sensory recalibration — the brain's automatic correcting of errors in our sensory or perceptual systems — can occur instantly.
"Until recently, neuroscientists thought of sensory recalibration as a mechanism that is primarily used for coping with long-term changes, such as growth during development, brain injury or stroke," said Ladan Shams, a UCLA assistant professor of psychology and an expert on perception and cognitive neuroscience. "It appeared that extensive time, and thus many repetitions of error, were needed for mechanisms of recalibration to kick in. However, our findings indicate we don't need weeks, days, or even minutes or seconds to adapt. To some degree, we adapt instantaneously.
"If recalibration can occur in milliseconds, as we now think, then we can adapt even to transient changes in the environment and in our bodies.
"In Shams' study, reported in the March 23 issue of the Journal of Neuroscience, 146 individuals, primarily UCLA undergraduates, performed what is known as a fundamental perceptual task. They looked at the center of a large screen that had eight speakers hidden behind it. Sometimes they heard only a brief burst of sound somewhat like radio static; sometimes they saw only a quick flash of light; and sometimes they both heard a sound and saw a light. They were asked to determine where the sound was and where the light was.
They participants, the researchers found, were much more accurate in determining where the light was than where the sound was.