Identification of Emotional Facial Expressions: Effects of Expression, Intensity, and Sex on Eye Gaze

Abstract

The identification of emotional expressions is vital for social interaction, and can be affected by various factors, including the expressed emotion, the intensity of the expression, the sex of the face, and the gender of the observer. This study investigates how these factors affect the speed and accuracy of expression recognition, as well as dwell time on the two most significant areas of the face: the eyes and the mouth. Participants were asked to identify expressions from female and male faces displaying six expressions (anger, disgust, fear, happiness, sadness, and surprise), each with three levels of intensity (low, moderate, and normal). Overall, responses were fastest and most accurate for happy expressions, but slowest and least accurate for fearful expressions. More intense expressions were also classified most accurately. Reaction time showed a different pattern, with slowest response times recorded for expressions of moderate intensity. Overall, responses were slowest, but also most accurate, for female faces. Relative to male observers, women showed greater accuracy and speed when recognizing female expressions. Dwell time analyses revealed that attention to the eyes was about three times greater than on the mouth, with fearful eyes in particular attracting longer dwell times. The mouth region was attended to the most for fearful, angry, and disgusted expressions and least for surprise. These results extend upon previous findings to show important effects of expression, emotion intensity, and sex on expression recognition and gaze behaviour, and may have implications for understanding the ways in which emotion recognition abilities break down.

In the eyes of the beholder: investigating the effect of visual probing on accuracy and gaze fixations when attending to facial expressions among primary and secondary callous-unemotional variants

“…We failed to find that individuals with primary or secondary CU traits showed fewer fixations to the eye region specifically when processing facial expressions [5,40]. Instead, all participants, regardless of levels of CU traits most frequently attended to the mouth and eye regions of the face when processing facial expressions, compared to less visited forehead area, consistent with prior research [39,41]. The inconsistency in findings may be attributed to methodological differences between studies in task parameters (i.e., verbal cue vs visual cue, static vs. dynamic facial stimuli) and group formation, discussed in greater detail below.…”

Discovering gender differences in facial emotion recognition via implicit behavioral cues

“…Fig.4(a-c) show that the eye, mouth and nasal face regions attract maximum visual attention during facial emotion recognition, in line with prior studies such as [10], [18]. Prior works such as [22] have also observed that females look up to the eyes for emotional cues, which is mirrored by longer female fixations around the eyes in the no mask and mouth mask conditions. Fig.4(b) suggests that when eye information is unavailable, females tend to concentrate on the mouth and nasal regions for emotional cues.…”

Familiarity facilitates detection of angry expressions

“…Our stimuli with happy expressions were detected faster and more accurately than were our stimuli with angry expressions. In general, others have found that happy expressions are recognized with highest accuracy compared to the other canonical expressions (Kirouac & Doré, 1983;Kirita & Endo, 1995;Leppänen et al, 2003;Wells et al, 2016). The absence of an effect of familiarity on the detection of the happy expression suggests that this process is optimized, perhaps because it is such a common social cue for interactions with both familiar and unfamiliar others.…”