Rapid global form binding with loss of associated colors.

Distributed neural processing creates a binding problem: the representations of the various features of an object are distributed across brain areas but must be associated with, or bound to, the same object. Here we determine the limits that binding imposes on the perception of global form in static flow fields defined by oriented dot pairs. The binding of local orientation signals into global form is shown to operate at rapid 20-Hz rates, implying that visual signals at the point of global form extraction retain precise temporal registration. Binding global form with color is limited to rates of 3-5Hz, showing that binding across attributes can impose a severe temporal limit on perception. Judgment of the temporal sequence of the global structures is also limited to slow rates. These results point to a substantial loss of temporal resolution in the visual system following the extraction of global form but preceding visual awareness.