Time - an important factor in object recognition

DECEMBER 11, 2008--Human eyes never see the same image twice. An object such as a cat can produce innumerable impressions on the retina, depending on the direction of gaze, angle of view, distance, and so forth. Every time our eyes move, the pattern of neural activity changes, yet our perception of the cat remains stable. "This stability, which is called 'invariance,' is fundamental to our ability to recognize objects -- it feels effortless, but it is a central challenge for computational neuroscience," explained James DiCarlo of the McGovern Institute for Brain Research at MIT, the senior author of the new study appearing in a recent issue of Science. "We want to understand how our brains acquire invariance and how we might incorporate it into computer vision systems." A possible explanation is suggested by the fact that our eyes tend to move rapidly (about three times per second), whereas physical objects usually change more slowly. Therefore, differing patterns of activity in rapid succession often reflect different images of the same object. Could the brain take advantage of this simple rule of thumb to learn object invariance? For more information, go to: http://web.mit.edu/newsoffice/2008/neuron-object-0911.html