Subthreshold features of visual objects: unseen but not unbound.

The object is a basic unit that is thought to organize the way in which we perceive and think about the world. According to theories of object-based attention, perception of unified objects depends on the binding together of the disparate features of each object via attention. Here we show that a visual feature that is not consciously perceived is nonetheless modulated by object-based attention: the influence of a subthreshold motion signal (prime) on subsequent motion perception depended critically on whether it was associated with the attended object or another, spatially overlapping object. These results show that invisibly weak features of attended objects are not lost, but are organized by and selected together with the object by attention.