Holistic processing does not require configural variability

Abstract

Using the Garner speeded classification task, Amishav and Kimchi (Psychonomic Bulletin & Review, 17, 743-748, 2010) found that participants could selectively attend to face features: Classifying faces based on the shape of the eyes was not influenced by task-irrelevant variation in the shape of the mouth, and vice versa. This result contrasts with a large body of work using another selective attention task, the composite task, in which participants are unable to selectively attend to face parts: Same/different judgments for one-half of a composite face are influenced by the same/different status of the task-irrelevant half of that composite face. In Amishav and Kimchi, faces all shared a common configuration of face features. By contrast, configuration is typically never controlled in the composite task. We asked whether failures of selective attention observed in the composite task are caused by faces varying in both features and configuration. In two experiments, we found that participants exhibited failures of selective attention to face parts in the composite task even when configuration was held constant, which is inconsistent with Amishav and Kimchi's conclusion that face features can be processed independently unless configuration varies. Although both measure failures of selective attention, the Garner task and composite task appear to measure different mechanisms involved in holistic face perception.

Figure 1

Schematic of the trial types in the complete design of the composite task. The study face is always aligned. On misaligned trials, the test face is misaligned.

Figure 2

A) Same-configuration (SC) and different-configuration (DC) faces (adapted from Kimchi & Amishav, 2010, Experiment 3) used to make composite faces. Faces were cut in half to produce face tops and bottoms that were randomly combined within each set to create composites for SC and DC groups, respectively. B) Example top-same-incongruent trial in the SC and DC conditions. The correct response to the target part (top) is “same” and the irrelevant bottom half is differs between study and test. In the SC condition the “different” bottom shows a different feature. In the DC condition, the “different” bottom shows a different feature in a different configuration (i.e., different nose-mouth distance).

Figure 3

Sensitivity (d’) as a function of alignment and congruency for the DC and SC groups in Experiment 1. Error bars show 95% confidence intervals of the within-subject effect, calculated separately for each configuration group.

Figure 4

Sensitivity (d’) as a function of alignment and congruency for the DC and SC groups in Experiment 2. Error bars show 95% confidence intervals of the within-subject effect, calculated separately for each configuration group.