Abstract
Parkes et al. (2001) showed that when an object is crowded, although specific features of the object do not reach awareness, this information is not completely lost; rather, it is incorporated into precise ensemble statistics about the entire set. Thus it appears that a detailed representation of a crowded object survives at least until an averaging stage in the processing stream. Recently, it was established that higher-level objects such as faces and houses can be readily crowded using appropriate distractors. It has also been shown that observers can accurately report ensemble statistics, such as mean emotion, from a set of faces. Here, we tested whether a face that is crowded from perception can nonetheless influence observers' judgments about the ensemble statistics of the set in which it falls. Subjects simultaneously viewed two sets of faces in which a central face was crowded by six flanking faces. Individual faces varied on an emotional range from neutral to disgusted, and the mean emotion of each set was manipulated independently of the emotion of the central, crowded face. In separate runs, subjects were asked to make two judgments: 1) Which central face was more disgusted? 2) Which set of faces was more disgusted, on average? Despite observers' inability to determine which crowded face was more disgusted (performance was near chance on the individual face judgment), the emotions of the central faces substantially influenced judgments about the relative mean emotions of the two sets. The results demonstrate that despite observers' inability to access specific information about a crowded face, such information remains intact at least until the stage at which an ensemble representation is generated. Thus, averaging occurs subsequent to holistic face processing, or at multiple levels in the processing stream.
Supported by an NIH NRSA Vision Science Training Grant.