Why are you looking like that? How the context influences evaluation and processing of human faces

Abstract

Perception and evaluation of facial expressions are known to be heavily modulated by emotional features of contextual information. Such contextual effects, however, might also be driven by non-emotional aspects of contextual information, an interaction of emotional and non-emotional factors, and by the observers' inherent traits. Therefore, we sought to assess whether contextual information about self-reference in addition to information about valence influences the evaluation and neural processing of neutral faces. Furthermore, we investigated whether social anxiety moderates these effects. In the present functional magnetic resonance imaging (fMRI) study, participants viewed neutral facial expressions preceded by a contextual sentence conveying either positive or negative evaluations about the participant or about somebody else. Contextual influences were reflected in rating and fMRI measures, with strong effects of self-reference on brain activity in the medial prefrontal cortex and right fusiform gyrus. Additionally, social anxiety strongly affected the response to faces conveying negative, self-related evaluations as revealed by the participants' rating patterns and brain activity in cortical midline structures and regions of interest in the left and right middle frontal gyrus. These results suggest that face perception and processing are highly individual processes influenced by emotional and non-emotional aspects of contextual information and further modulated by individual personality traits.

Fig. 1

Experimental paradigm (adapted and modified from Kim et al., 2004). A fixation cross was shown during both, the interstimulus interval (ISI) and intertrial interval (ITI).

Fig. 2

Brain activity for the contrast self-related vs other-related (whole-brain analysis, P < 0.005, uncorrected, k = 10 contiguous voxels) and parameter estimates extracted from a sphere (r = 5 mm) centered on the respective peak voxel. (A) Increased activity in the medial prefrontal cortex (mPFC; x = −6, y = 62, z = 22). (B) Increased activity in the right fusiform gyrus (x = 34, y = −58, z = −16). Error bars represent 95% within-subject confidence intervals (CIs). ***P < 0.001, **P < 0.005.

Fig. 3

(A and B) Correlation of the participants' Brief Fear of Negative Evaluation (BFNE) scores and brain activity in the contrast self-related/negative vs other-related/negative. (A) Whole-brain analysis (P < 0.005, uncorrected, k = 10 contiguous voxels) showing significant correlations with BFNE scores in the left medial prefrontal cortex (mPFC) and the left middle frontal gyrus (MFG). (B) ROI-analysis based on coordinates of Blair et al., 2008, P < 0.05, FWE corrected, k = 10 contiguous voxels. The ROI lies within the left MFG activation that can also be seen in Figure 3A. (C) Correlation of the participants’ BFNE scores with beta values extracted from the ROI based on coordinates of Blair et al. (2008); r = 0.552, P = 0.005. L = left.