Minor structural abnormalities in the infant face disrupt neural processing: A unique
window into early caregiving responses
Abstract:
Infant faces elicit early, specific activity in the orbitofrontal cortex (OFC), a key cortical region
for reward and affective processing. A test of the causal relationship between infant facial
configuration and OFC activity provided by naturally occurring disruptions to the face
structure. One such disruption is cleft lip, a small change to one facial feature, shown to
disrupt parenting. Using MEG, we investigated neural responses to infant faces with cleft lip
compared with typical infant and adult faces. We found activity in the right OFC at 140 ms in
response to typical infant faces but diminished activity to infant faces with cleft lip or adult
faces. Activity in the right fusiform face area was of similar magnitude for typical adult and
infant faces but was significantly lower for infant faces with cleft lip. This is the first evidence
that a minor change to the infant face can disrupt neural activity potentially implicated in
caregiving.
Summary of the article:
Prior to the onset of language, the parent’s ability to ‘read’ their infant’s face is fundamental
to early interpersonal communication and interactions. Adults are remarkably attuned to the
facial features that characterize their young, including a large rounded forehead, large low-
set eyes, a short and narrow nose and a small chin. These features are considered to have
a putative role in eliciting caregiving responses. Because cleft lip does not fit in this ‘’infant
schema’’, children with such disruption are at raised risk for adverse outcomes in social,
emotional, and cognitive functioning. Disrupted processing of the infant's face may help
account for some of the early difficulties in parent-infant interaction.
Participants of the experiment were presented with images of faces of typical adults, typical
infants, and infants with cleft lip. Participants performed an ‘implicit’ viewing task, where they
were required to fixate on a red cross at all times, and to press a button when the cross
changed colour to green. During the task, the fixation cross was replaced by images of infant
faces, adult faces, or infant faces with cleft lip. During image presentation, participants were
instructed to maintain their gaze where the fixation cross formerly was.
Source reconstruction revealed right OFC activity at 140 ms in response to infant faces but
not to adult faces or infant faces with cleft lip. This indicates that the structural abnormality,
cleft lip, has a marked impact upon adults’ neural processing of infant faces. The diminished
OFC activity in response to the infant faces with cleft lip indicates a substantial change in
reward-related affective responses from that seen for typical infants.
, Frontal EEG Asymmetry and Fear Reactivity in Different Contexts at 10 Months
Diaz, A. & Bell, M. A.
Abstract:
Individual differences in observed and maternal-rated fear behaviors and frontal
electroencephalogram (EEG) asymmetry were examined in normally developing 10-month-
old infants. EEG was recorded during resting baseline, as well as during stranger approach,
mask presentation, and toy spider presentation. Mothers completed the Infant Behavior
Questionnaire. For mask presentation, baseline and task right frontal EEG asymmetry as
well as maternal ratings predicted fear behavior during the mask task. For stranger
approach, task-related right frontal EEG asymmetry predicted fear behavior during stranger
approach after controlling for baseline asymmetry. There was a trend for task-related right
frontal EEG asymmetry to predict fear during presentation of a toy spider after controlling for
baseline asymmetry. Maternal report of temperament only added unique variance to the
prediction of one fear task after controlling for baseline and task EEG. Assessing fear in
multiple situations revealed context-specific individual differences in infant fear.
Summary of the article
Newborns exhibit a startle response to stimuli that display loud noises. With normal
development, infants become less driven by these startle reflexes and begin to show a range
of fear behaviors in response to various types of novel stimuli. Because infants are regularly
confronted with unfamiliar stimuli or situations, examining the manifestation of fear in various
contexts is vital to understanding infant emotional development.
Temperament is the biological basis of individual differences in emotion reactivity and its
regulation. Researchers have measured temperament-related fear behaviors using different
procedures, a common one being a social fear-inducing task focused on stranger
approaches. In this procedure, the child is observed in the unfamiliar research lab while a
stranger enters the room, creating a context of increased unfamiliarity. Fear is also
measured in non-social contexts with relatively mild and non-intrusive stimuli, such as
masks, animals, or spontaneous moving toys.
In addition to assessments of fear behaviors in the research lab, maternal ratings of infant
temperament have been used to assess temperamental fear behaviors in various contexts
outside for the laboratory setting. Temperament questionnaires such as the Infant Behavior
Questionnaire-Revised have shown good internal consistency and converge with other
similar scales. Both research lab and questionnaire methodologies indicate variability among
typically developing infants in their fear-related behaviors.
Indeed, infants respond to fearful emotional events with a set of highly integrated
neurobiological responses Brain electrical activity correlates of emotion have been noted in
the first year of life, suggesting that different types of emotion are associated with different
patterns of frontal activation. The Fox model of frontal asymmetry proposes that activation of
the right hemisphere during a resting baseline condition is associated with the tendency to
display withdrawal types of behaviors and emotions, whereas activation of the left
hemisphere is associated with the tendency to exhibit approach types of behaviors and
emotions. For example, infants who exhibit resting right frontal EEG asymmetry are more
likely to cry when separated from their mothers compared to infants who exhibit left frontal
