Preparatory attention incorporates contextual expectations

Humans are remarkably proficient at finding objects within a complex visual world. Current theories of attentional selection propose that this ability is mediated by target-specific preparatory activity in visual cortex, biasing visual processing in favor of the target object. In real-world situations, however, the retinal image that any object will produce is unknown in advance; its size, for instance, varies dramatically with the object’s distance from the observer. Using fMRI, we show that preparatory activity is systematically modulated by expectations derived from scene context. Human participants searched for objects at different distances in scenes. Activity patterns in object-selective cortex during search preparation (while no objects were presented), resembled activity patterns evoked by viewing targets object in isolation. Crucially, this preparatory activity was modulated by distance, reflecting the predicted retinal image of the object at each distance. These findings reconcile current theories of attentional selection with the challenges of real-world vision.

Highlights

• Visual cortex contains object-specific representations during search preparation.

• We demonstrate this for the first time during concurrent visual scene processing.

• Preparatory object representations are scaled to account for viewing distance.

• Preparatory biases reflect the predicted retinal image inferred from scene context.

eTOC blurb

Attentional selection is thought to be mediated by target-specific preparatory activity in visual cortex. Gayet and Peelen provide evidence that such preparatory biases incorporate contextual expectations about object appearance, reconciling attention theories with the challenges of naturalistic vision.