"Humans do a rough categorization of objects very quickly," Connor said. "For instance, in just a tenth of a second, we can recognize whether something we see is an animal or not. Our results show that this immediate, rough impression probably depends on recognizing just one or more individual parts of what we see. Fine discriminations ?such as recognizing individual faces ?take longer to happen, and our study suggests that this delay depends upon emerging signals for combinations of shape fragments. In a sense, the brain has to construct an internal representation of an object from disparate pieces."
In the long term, understanding exactly how the brain processes information may lead to neural prostheses ?artificial replacements for lost sensory, motor and perhaps even memory and cognitive functions. In the short term, such work is driven by curiosity about one of the fundamental mysteries: how the brain works.
"Our ability to see is one of the great evolutionary accomplishments of the human brain," Connor said. "We still don't know how the visual system accomplishes this marvel of information processing. Such experiments are beginning to reveal how large networks of neurons in the brain extract meaning from the eye image."