Neural correlates of facial emotion processing in infancy

Abstract

In the present study we examined the neural correlates of facial emotion processing in the first year of life using ERP measures and cortical source analysis. EEG data were collected cross-sectionally from 5-(N = 49), 7-(N = 50), and 12-month-old (N = 51) infants while they were viewing images of angry, fearful, and happy faces.The N290 component was found to be larger in amplitude in response to fearful and happy than angry faces in all posterior clusters and showed largest response to fear than the other two emotions only over the right occipital area. The P400 and Nc components were found to be larger in amplitude in response to angry than happy and fearful faces over central and frontal scalp. Cortical source analysis of the N290 component revealed greater cortical activation in the right fusiform face area in response to fearful faces. This effect started to emerge at 5 months and became well established at 7 months, but it disappeared at 12 months. The P400 and Nc components were primarily localized to the PCC/Precuneus where heightened responses to angry faces were observed. The current results suggest the detection of a fearful face in infants' brain can happen shortly (~200-290 ms) after the stimulus onset, and this process may rely on the face network and develop substantially between 5 to 7 months of age. The current findings also suggest the differential processing of angry faces occurred later in the P400/Nc time window, which recruits the PCC/ Precuneus and is associated with the allocation of infants' attention. K E Y W O R D S cortical source analysis, ERPs, infant facial emotion processing S U PP O RTI N G I N FO R M ATI O N Additional supporting information may be found online in the Supporting Information section at the end of the article. How to cite this article: Xie W, McCormick SA, Westerlund A, Bowman LC, Nelson CA. Neural correlates of facial emotion processing in infancy. Dev Sci. 2019;22:e12758.

Neural responses to happy, fearful and angry faces of varying identities in 5- and 7-month-old infants

“…At least one fMRI study in adults (Zhang et al, 2016) and another fNIRS study in infants (Grossmann et al, 2018) also do not report differential activations to different types of facial emotions over temporal cortices. Interestingly, and contrary to previous reports in behavioral and ERP paradigms Xie et al, 2018), no differences between 5-and 7-month-olds were found. Because ERP and fNIRS paradigm differ in paradigm design, response temporality, and underlying neural sources, some or all of these differences may account for the differences in findings.…”

“…fNIRS has also revealed that medial frontal regions are implicated in processing happy faces in infants from 9-13 months (Minagawa-Kawai et al, 2009) and linked individual differences in frontal responses to emotional faces with earlier epigenetic changes (Krol et al, 2019) and later behavior (Grossmann et al, 2018). However, no studies to date have directly tested for differences in neural activity between 5 and 7 months, a critical time window during which differential responses to fearful faces are often first observed with ERP (Leppänen, Richmond, Vogel-Farley, Moulson, & Nelson, 2009;Xie, McCormick, Westerlund, Bowman, & Nelson, 2018). In addition, no prior infant fNIRS study has examined responses to facial emotions when facial identity varies, a focus of classic behavioral studies in this age group (Bayet & Nelson, 2019;), or in relation to simultaneous looking behavior to facial features.…”

Emotion in motion: Facial dynamics affect infants' neural processing of emotions

“…Additionally, differential processing of emotional faces was also found in a recent cross-sectional study comparing the amplitude of the N290 and P400 components and determining their specific cortical sources in 5-, 7-, and 12-month-old infants while they were viewing angry, fearful, and happy faces (Xie et al, 2018).…”

“…Further studies examining the N290 found it to be larger in response to fearful compared to angry faces (Hoehl & Striano, ) and happy faces (van den Boomen, Munsters, & Kemner, ). Additionally, differential processing of emotional faces was also found in a recent cross‐sectional study comparing the amplitude of the N290 and P400 components and determining their specific cortical sources in 5‐, 7‐, and 12‐month‐old infants while they were viewing angry, fearful, and happy faces (Xie et al, ). Indeed, regardless of infants' age, N290 responses were greater to fearful and happy faces compared to angry expressions, and while P400 responses were found to be greater in response to angry than happy and fearful faces.…”

“…Electrophysiological evidence of infants' sensitivity to anger is very scarce, and rather mixed. There is evidence that, by the end of the first year of life, infants can discriminate between facial expressions of anger and neutral facial expressions (Stahl, Parise, Hoehl, & Striano, 2010) and other negative emotions (Kobiella et al, 2008;Xie, McCormick, Westerlund, Bowman, & Nelson, 2018). Indeed, greater attention allocation, as indexed by larger Nc, was observed in response to angry facial expressions compared to expressions of fear (Kobiella et al, 2008) and pain (Missana et al, 2014).…”