Involuntary Facial Expression Processing: Extracting Information from Two Simultaneously Presented Faces

Samantha Baggott,Mark A Williams,Romina Palermo,Manos Tsakiris

doi:10.1371/journal.pone.0022287

Abstract

Facial expressions play an important role in successful social interactions, with previous research suggesting that facial expressions may be processed involuntarily. In the current study, we investigate whether involuntary processing of facial expressions would also occur when facial expression distractors are simultaneously presented in the same spatial location as facial expression targets. Targets and distractors from another stimulus class (lions) were also used. Results indicated that angry facial expression distractors interfered more than neutral face distractors with the ability to respond to both face and lion targets. These findings suggest that information from angry facial expressions can be extracted rapidly from a very brief presentation (50 ms), providing compelling evidence that angry facial expressions are processed involuntarily.

Highlights

In everyday life we are constantly exposed to a vast number of competing sources of information
Greenhouse-Geisser correction was applied where the assumption of sphericity was violated. This initial analysis was performed to ensure that participants were focusing on the sex classification task
The current study aimed to test the hypothesis that facial expressions are processed involuntarily., when the emotion of the facial expressions was task irrelevant and the dissimilarity between targets and distractors was minimised

Summary

Introduction

In everyday life we are constantly exposed to a vast number of competing sources of information. To drive along a busy street, for example, it is critical that we attend to relevant information (e.g., other vehicles, pedestrians, traffic lights and road signs) at the expense of irrelevant information that may demand attention (e.g., flashing advertisements). It seems to be difficult, though, to ignore evolutionarily or biologically specified irrelevant information. Faces are biologically and socially important for signalling the race, age and sex of an individual, as well as whether they are friend or foe It follows, that irrelevant faces should be difficult to ignore. Consistent with this, recent studies have demonstrated that the sex and identity of a face continues to be processed even when that face is task irrelevant, suggesting that some aspects of face processing occur involuntarily [1,2,3,4]

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Results

Conclusion