Getting the Picture

How does the brain build a comprehensible picture of the visible world? Research over recent decades has taught us that the brain does not, in fact, process a given scene as a whole. Instead parts of the brain work independently and in parallel to process information about various aspects of each figure - location, form, color and movement. If we watch, say, a camel trot in front of a palm tree in a desert, we perceive the camel's swaying motion and dusky hue separate from its humped form. How the brain links such features into a complete picture is not well understood and is dreaded by scientists as the "binding problem": How does a feature bind to "its" object? Why don¿¿t we experience erroneous bindings more frequently? Our group at the University of Bremen in Germany is systematically exploring such questions in a series of experiments. By showing subjects small visual inputs for barely detectable fractions of a second, we stress the visual system so that it reveals some of its secrets.