The role of early adversity and cognitive vulnerability in postnatal stress and depression

The purpose of the present study was to examine vulnerability factors in expecting parents that might lead to mental illness in the perinatal period. Specifically, we studied how parental early adversity, attentional bias to infant faces, repetitive negative thinking, and demographic factors, were associated with pre- and postnatal depressive symptoms and parenting stress. Participants were expecting parents taking part in the Northern Babies Longitudinal Study, where assessments were made both pre- and postnatally. Assessments included both questionnaires and cognitive tasks. About half of the participants received the Newborn Behavior Observation (NBO)-intervention after birth, between pre- and postnatal assessments. Results show that repetitive negative thinking was a significant predictor of both depressive symptoms and parenting stress, while education, social support, and parity came out as protective factors, especially in mothers. Parental early adversity had an indirect effect on postnatal depressive symptoms and parenting stress, mediated by prenatal and postnatal depressive symptoms, respectively. The NBO intervention did not affect the results, signifying the importance of early childhood adverse events and negative thinking on parents' postnatal adjustment and mood, even when an intervention is provided. In conclusion, repetitive negative thinking is a significant vulnerability factor independent of the presence of depressive symptoms, and health professionals must be aware of parents’ thinking style both during pregnancy and after birth.

Validation of the City Infant Faces Database in Student and Parent Samples

The City Infant Faces Database (CIFD; Webb et al., 2018) is a database of 154 infant emotional expressions for use in experimental studies of infant facial communication, facial expression recognition, and parental sensitivity. The CIFD was validated only in a small sample from the general public and student midwives and nurses in the UK. This study, therefore, aimed to validate it in a larger sample of Croatian students and parents of 1-12 months old infants. Three-hundred and fifty students (Study 1), 422 mothers and 106 fathers (Study 2) were presented with images of Caucasian infant faces. The students rated images from the CIFD and Tromsø Infant Faces. They also completed questionnaires measuring empathy, alexithymia, and perceiving and expressing emotions. The parents rated the valence of facial expressions of images from the CIFD. The results were consistent with the initial validation in both the students and parents’ sample, except that agreement for negative images was lower for Croatian parents than in the UK study. Compared to the UK study, students rated images as more intense, clear, genuine, and reported stronger internal emotion. Furthermore, there was no difference in accuracy between mothers and fathers or between first-time parents and experienced parents. The CIFD is, therefore, a promising tool for research and should be further validated in other countries, focusing on its predictive validity.

Impairment effect of infantile coloration on face discrimination in chimpanzees

Impaired face recognition for certain face categories, such as faces of other species or other age class faces, is known in both humans and non-human primates. A previous study found that it is more difficult for chimpanzees to differentiate infant faces than adult faces. Infant faces of chimpanzees differ from adult faces in shape and colour, but the latter is especially a salient cue for chimpanzees. Therefore, impaired face differentiation of infant faces may be due to a specific colour. In the present study, we investigated which feature of infant faces has a greater effect on face identification difficulty. Adult chimpanzees were tested using a matching-to-sample task with four types of face stimuli whose shape and colour were manipulated as either infant or adult one independently. Chimpanzees' discrimination performance decreased as they matched faces with infant coloration, regardless of the shape. This study is the first to demonstrate the impairment effect of infantile coloration on face recognition in non-human primates, suggesting that the face recognition strategies of humans and chimpanzees overlap as both species show proficient face recognition for certain face colours.

Secure Attachment Priming Amplifies Approach Motivation for Infant Faces Among Childless Adults

Existing studies have indicated that priming secure attachment alters adults’ neural responses to infant faces. However, no study has examined whether this effect exists for motivational behavioral responses, and none of the previous studies included adult faces as a baseline to determine whether the security prime enhances responses to human faces in general or infant faces alone. To address this limitation, the current study recruited 160 unmarried and childless adults in the first phase, and all of them completed a battery of questionnaires, including the Interest in Infants, the Experiences in Close Relationships (ECR), and State Adult Attachment Measure (SAAM). A week later, after priming, 152 (76 security-primed vs. 76 neutrally primed) participants completed the SAAM and a behavioral program assessing their motivational responses to both adult and infant faces (i.e., liking, representational, and evoked responses). A manipulation check showed that the security prime was effective. Then, generalized linear mixed-effects models (GLMMs) showed that security priming enhances adults’ liking, representational, and evoked responses (three components of the motivational system) only to infant faces and not to adult faces. Moreover, hierarchical regression analysis indicated that, even after security priming, there was a substantial linear relationship between positive motivation toward infant faces and the state of adult secure attachment. In summary, this study demonstrated for the first time that promoting the state of adult secure attachment can effectively enhance the effect size of the baby face schema. The current results were interpreted according to Bowlby’s view of the attachment behavioral system.

No evidence of spatial representation of age, but “own-age bias” like face processing found in chimpanzees

Previous studies have revealed that non-human primates can differentiate the age category of faces. However, the knowledge about age recognition in non-human primates is very limited and whether non-human primates can process facial age information in a similar way to humans is unknown. As humans have an association between time and space (e.g., a person in an earlier life stage to the left and a person in a later life stage to the right), we investigated whether chimpanzees spatially represent conspecifics’ adult and infant faces. Chimpanzees were tested using an identical matching-to-sample task with conspecific adult and infant face stimuli. Two comparison images were presented vertically (Experiment 1) or horizontally (Experiment 2). We analyzed whether the response time was influenced by the position and age category of the target stimuli, but there was no evidence of correspondence between space and adult/infant faces. Thus, evidence of the spatial representation of the age category was not found. However, we did find that the response time was consistently faster when they discriminated between adult faces than when they discriminated between infant faces in both experiments. This result is in line with a series of human face studies that suggest the existence of an “own-age bias.” As far as we know, this is the first report of asymmetric face processing efficiency between infant and adult faces in non-human primates.

Emotional Infant Face Processing in Women With Major Depression and Expecting Parents With Depressive Symptoms

Processing of emotional facial expressions is of great importance in interpersonal relationships. Aberrant engagement with facial expressions, particularly an engagement with sad faces, loss of engagement with happy faces, and enhanced memory of sadness has been found in depression. Since most studies used adult faces, we here examined if such biases also occur in processing of infant faces in those with depression or depressive symptoms. In study 1, we recruited 25 inpatient women with major depression and 25 matched controls. In study 2, we extracted a sample of expecting parents from the NorBaby study, where 29 reported elevated levels of depressive symptoms, and 29 were matched controls. In both studies, we assessed attentional bias with a dot-probe task using happy, sad and neutral infant faces, and facial memory bias with a recognition task using happy, sad, angry, afraid, surprised, disgusted and neutral infant and adult faces. Participants also completed the Ruminative Responses Scale and Becks Depression Inventory-II. In study 1, we found no group difference in either attention to or memory accuracy for emotional infant faces. Neither attention nor recognition was associated with rumination. In study 2, we found that the group with depressive symptoms disengaged more slowly than healthy controls from sad infant faces, and this was related to rumination. The results place emphasis on the importance of emotional self-relevant material when examining cognitive processing in depression. Together, these studies demonstrate that a mood-congruent attentional bias to infant faces is present in expecting parents with depressive symptoms, but not in inpatients with Major Depression Disorder who do not have younger children.

Do Infant Faces Maintain the Attention of Adults With High Avoidant Attachment?

We investigated whether adults have attentional bias toward infant faces, whether it is moderated by infant facial expression, and the predictive effect of the adult attachment state on it. One hundred unmarried nulliparous college students [50 men and 50 women; aged 17–24 years (M = 19.70, SD = 1.35)] were recruited. Each completed a self-report questionnaire—the Chinese version of the State Adult Attachment Measure (SAAM), and a dot-probe task with a stimulus presentation duration of 500 ms, which used 192 black-and-white photographs of 64 people (32 infants and 32 adults; each person displayed three expressions: happy, neutral, and sad) as the experimental stimuli. The results showed that, at the duration of 500 ms, individuals' attentional bias toward infant faces disappeared, regardless of the facial expression. However, when the interaction between avoidant attachment state and face was controlled, the attentional bias was significant again, and the avoidant attachment state negatively predicted individuals' attentional bias toward infant faces. This indicates that at the suprathreshold stage, there are individual differences in the attentional bias toward infant faces, and high avoidant attachment will weaken individuals' attentional bias toward infant faces. This study advances previous studies that focused only on individuals' attention to infant faces occurring at the early processing stage of attention. The results provide direction for interventions; specifically, changing the attachment state of avoidant individuals can affect their attention to infants, which may promote the establishment of parent–child relationships.

EXPRESS: Adults’ Responses to Infant Faces: Neutral Infant Facial Expressions Elicit the Strongest Baby Schema Effect

The effect of the babyface schema includes three typical responses, namely, the preference response, viewing motivation, and attention bias towards infant faces. It has been theorized that these responses are primarily influenced by infants’ facial structures. However, recent studies have revealed the moderating role of facial expression, suggesting that the strongest effect of the babyface schema may be related to the neutral facial expression; this hypothesis remains to be tested. In this study, the moderating role of facial expression was assessed in three successive experiments (total N = 402). We used a series of images of the same face with multiple expression-standardized images of infants and adults to control for facial structure. The results indicated that the effect sizes of the babyface schema (i.e., response differences between infants and adults) were different for multiple expressions of the same face. Specifically, the effect sizes of neutral faces were significantly greater than those of happy and sad faces according to the preference response (experiment 1, N = 90), viewing motivation (experiment 2, N = 214), and attentional bias (experiment 3, N = 98). These results empirically confirm that neutral infant facial expressions elicit the strongest effect of the babyface schema under the condition of using adult faces as a comparison baseline and matching multiple expressions of the same face.