Statistical Properties Demand as Much Attention as Object Features

Recent studies have argued that the statistical properties of a set of visual items can be extracted with little or even no cost. In the present study, observers (N = 188) performed a color task and an orientation task, and the attention effect was measured as the advantage of pre-cueing one of the two tasks. The color and orientation tasks required participants to report either an object feature or the mean of a 4×4 array (i.e., statistical property). The pre-cueing advantages were approximately equal regardless of the nature of the tasks (object features vs. statistical properties), providing evidence that statistical properties are not perceived with zero cost, but demand as much attention as object features.