THE NEURAL GENERATION OF A UNIFIED ILLUSION IN HUMAN VISION

THE neural mechanisms of visual binding in humans were investigated by measuring the brain's high-frequency electric responses (36-44 Hz) to the subjective visual perception of a unified three-dimensional illus ion. 40 Hz synchronization was found over occipital and right parieto- temporal areas 500-300 ms before visual awareness of the three-dimensi onal Gestalt was reported, but not during the viewing of the illusion. At lower frequency bands (8-13 Hz and 13-20 Hz) no corresponding sync hronization was found. 40 Hz synchronization thus directly correlates with the construction and emergence of a unified visual percept and ma y reflect the rapid formation of transient functional connections betw een spatially separated cortical areas.