Impact of Childhood Maltreatment on the Recognition of Facial Expressions of Emotions

Abstract

The development of the explicit recognition of facial expressions of emotions can be affected by childhood maltreatment experiences. A previous study demonstrated the existence of an explicit recognition bias for angry facial expressions among a population of adolescent Sierra Leonean street-boys exposed to high levels of maltreatment. In the present study, the recognition bias for angry facial expressions was investigated in a younger population of street-children and age-matched controls. Participants performed a forced-choice facial expressions recognition task. Recognition bias was measured as participants' tendency to over-attribute anger label to other negative facial expressions. Participants' heart rate was assessed and related to their behavioral performance, as index of their stress-related physiological responses. Results demonstrated the presence of a recognition bias for angry facial expressions among street-children, also pinpointing a similar, although significantly less pronounced, tendency among controls. Participants' performance was controlled for age, cognitive and educational levels and for naming skills. None of these variables influenced the recognition bias for angry facial expressions. Differently, a significant effect of heart rate on participants' tendency to use anger label was evidenced. Taken together, these results suggest that childhood exposure to maltreatment experiences amplifies children's "pre-existing bias" for anger labeling in forced-choice emotion recognition task. Moreover, they strengthen the thesis according to which the recognition bias for angry facial expressions is a manifestation of a functional adaptive mechanism that tunes victim's perceptive and attentive focus on salient environmental social stimuli.

Fig 1. Response Tendency.

Tendency rate for street-children (STch) and controls (Con). * = p < 0.005. Only between groups differences are shown. For differences within groups, see text. Error bars represent SE.

Fig 2. General-false-alarms.

General-false-alarms rate for street-children (STch) and controls (Con). * = p < 0.004. Only differences between groups are shown. For differences inside each group, see text. Error bars represent SE.

Fig 3. CPM-score predicts average General-false-alarms rate.

Plots of CMP-score versus average General-false-alarms for street-children (STch) and controls (Con). * = p < 0.05.

Fig 4. Fear and Sadness Emotion-false-alarms.

A) Fear Emotion-false-alarms for street-children (STch) and controls (Con). * = p<0.007. B) Sadness Emotion false alarms for street-children (STch) and controls (Con). * = p<0.006. Both panels show only differences between groups. For differences inside each group, see text. In both panels error bars represent SE.

Fig 5. CPM-score predicts average Fear Emotion-false-alarms.

Plot of participants’ CPM-score versus average Fear Emotion-false-alarms. * = p < 0.05.

Fig 6. Accuracy rate.

Accuracy rate for street-children (STch) and controls (Con). * = p < 0.004. Only differences between groups are shown. For differences inside each group, see text. Error bars represent SE.

Fig 7. CPM-score predicts average Accuracy rate.

Plots of CMP-score versus average Accuracy rate for street-children (STch) and controls (Con). * = p < 0.05.

Fig 8. HR predicts behavioral performance.

A) Plot of HR versus average Accuracy rate for street-children (STch) and controls (Con); B) Plot of HR versus Anger Tendency rate for street-children (STch) and controls (Con); C) Plot of HR versus Anger General-false-alarms rate for street-children (STch) and controls (Con). * = p < 0.01.