Object-based attention involves the sequential activation of feature-specific cortical modules

Abstract

Object-based theories of attention propose that the selection of an object's feature leads to the rapid selection of all other constituent features, even those that are task irrelevant. We used magnetoencephalographic recordings to examine the timing and sequencing of neural activity patterns in feature-specific cortical areas as human subjects performed an object-based attention task. Subjects attended to one of two superimposed moving dot arrays that were perceived as transparent surfaces on the basis either of color or speed of motion. When surface motion was attended, the magnetoencephalographic waveforms showed enhanced activity in the motion-specific cortical area starting at ∼ 150 ms after motion onset, followed after ∼ 60 ms by enhanced activity in the color-specific area. When surface color was attended, this temporal sequence was reversed. This rapid sequential activation of the relevant and irrelevant feature modules provides a neural basis for the binding of an object's features into a unitary perceptual experience.