A longitudinal comparison of maternal behaviour in German urban humans (Homo sapiens) and captive chimpanzees (Pan troglodytes).

Comparative perspectives are crucial in the study of human development, yet longitudinal comparisons of humans and other primates are still relatively uncommon. Here, we combined theoretical frameworks from cross-cultural and comparative psychology, to study maternal style in 10 mother-infant pairs of German urban humans (Homo sapiens) and 10 mother-infant pairs of captive chimpanzees (Pan troglodytes), during the first year of infants' development. We conducted focal observations of different behaviours (i.e. nursing, carrying, body contact, touching, grooming, restraining, approaching, leaving, rejection, aggression, mutual gaze, object stimulation), during natural interactions. Analyses revealed a more distal maternal style in WEIRD humans than in captive chimpanzees, with different behaviours being generally more common in one of the two species throughout development. For other behaviours (i.e. nursing), developmental trajectories differed between WEIRD humans and captive chimpanzees, although differences generally decreased through infants' development. Overall, our study confirms functional approaches as a valid tool for comparative longitudinal studies.

Face to face interactions in chimpanzee (Pan troglodytes) and human (Homo sapiens) mother-infant dyads.

Human mothers interact with their infants in different ways. In Western, educated, industrialized, rich and democratic (WEIRD) societies, face-to-face interactions and mutual gazes are especially frequent, yet little is known about their developmental trajectories and if they differ from those of other primates. Using a cross-species developmental approach, we compared mother-infant interactions in 10 dyads of urban humans from a WEIRD society (Homo sapiens) and 10 dyads of captive zoo-based chimpanzees (Pan troglodytes), when infants were one, six and 12 months old. Results showed that face-to-face interactions with mutual gaze events were common in both groups throughout the infant's first year of life. The developmental trajectories of maternal and infants' looks partially differed between species, but mutual gaze events were overall longer in humans than in chimpanzees. Mutual gazes were also more frequent in humans, peaking at six months in humans, while increasing with age in chimpanzees. The duration and frequency of mutual gazes varied across contexts in both groups, with mutual gazes being longer during caring/grooming and feeding contexts. These findings confirm that some aspects of early socio-cognitive development are shared by humans and other primates, and highlight the importance of combining developmental and cross-species approaches to better understand the evolutionary roots of parenting behaviour. This article is part of a discussion meeting issue 'Face2face: advancing the science of social interaction'.

Bewitched to Be Happy? The Impact of Pretend Play on Emotion Regulation of Expression in 3- to 6-Year-Olds.

As a means of psychological distancing, pretend play may facilitate emotion regulation. Up to now, however, the empirical evidence for a relation between these two is not consistent. The present study examines the impact of pretend play on reflective emotion regulation of expression with a disappointing gift task using the strategy of role-taking. Fifty-two children aged 3 to 6 years were motivated to deceive the experimenter volitionally by false smiling, regardless of whether they received an attractive gift, an unattractive gift, or no gift. Twenty-five of the children accomplished the task in the context of a pretend play where they were playfully guided to take on a role assumed to facilitate reflective emotion regulation of expression. The other 27 children received only a direct verbal instruction. As an indication of successful reflective emotion regulation of expression, twelve adult naïve observers judged children's videotaped behavior according to the quality of emotion that the children seemed to experience. This impression analysis showed no impact of experimental variation and thus no facilitating effect of pretend play with a given task-convenient role. While happiness ratings in the pretend play group did not correlate to children's quality of play, they positively correlated to children's joy of playing.

Expressions as signs and their significance for emotional development.

For research on emotional development, defining emotions as psychological systems of appraisals, expressions, body reactions, and subjective feelings in all phases of ontogenesis raises tricky methodological issues. How can we measure single emotions when appraisals and feelings cannot be assessed from outside, when expressions do not seem to be tied unequivocally to single emotions, and feelings are sometimes decoupled from perceivable expressions? Furthermore, how does a restricted set of neonate emotions differentiate into a culturally modified set of adult emotions? This article presents an innovative answer to these issues by applying Vygotsky's culture-historical approach on the psychological significance of social signs to the analysis of emotion, expression, and their development. The core assumption is that humans learn to use emotional expressions as communicative signs that appeal to another person to regulate their interaction through emotions and as psychological signs that appeal to the self to regulate the self's actions through emotions. This twofold function assigns a significant mediating role to expression for not only culture-historical and ontogenetic differentiation but also a growing awareness, self-regulation, and mental processing of emotions. The article describes three stages of emotional development supported by empirical evidence on how a biologically given set of neonate emotions are transformed into a culturally modified set of conscious, sign-mediated emotions that enables a decoupling of expression and feeling. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Impaired predictability: enhanced fluctuations in the parenting behaviour of mothers of pre-school children with clinical diagnoses across three different play tasks.

Fluctuations in parenting behaviour are thought to be important for the development of child psychopathology. This study focusses on fluctuations in the parenting behaviour of mothers with 3-6-year-old children with a clinical diagnosis according to the International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) (N = 39) and compared them with a control group of mothers with children without a clinical diagnosis (N = 41). In a laboratory setting, we compared the quality of mother-child interactions between both groups using three increasingly challenging co-operation tasks. At first, the mother and child interacted via a free play task. They then co-operated within a constructional play task and finally within a challenging problem-solving task. We analysed the mothers' parenting behaviour using the Laboratory Parenting Assessment Battery (LAB-PAB) and children's problem behaviours by means of their mothers' rating using the Child Behavior Checklist 1 ½-5 (CBCL). The results corroborated our hypotheses. Mothers of the group of children with clinical diagnoses had a lower parenting quality and higher fluctuations in parenting behaviour across situations compared with the non-clinical group. Further analysis revealed that specific fluctuations in maternal involvement and hostility uniquely predicted child psychopathology, measured with the CBCL, showing incremental validity of fluctuations in maternal involvement, when controlling for parenting quality and maternal difficulties in emotion regulation, measured with the Difficulties in Emotional Regulation scale. The results are discussed in terms of their implications for clinical interventions, as well as theoretical implications and future research.

Felt or false smiles? Volitional regulation of emotional expression in 4-, 6-, and 8-year-old children.

The development of volitional emotion regulation of expression was examined with a modified disappointing gift paradigm and strategy for coding children's expressions. Forty-nine boys and 49 girls aged 4, 6, and 8 were motivated to volitionally deceive an observer by false smiling, regardless of whether they received an attractive, unattractive, or no gift. Ten naïve observers watched children's videotaped behavior in random order and judged the quality of emotion and type of gift. This impression analysis indicated that children's competence to volitionally regulate their expressions increased with age. In addition, this ability was positively associated with children's emotion understanding of how to differentiate between emotion and expression. Unexpectedly, girls did not display a superior volitional regulation of expression than boys.

A cross-cultural comparison of the development of the social smile: a longitudinal study of maternal and infant imitation in 6- and 12-week-old infants.

Social smiling is universally regarded as being an infant's first facial expression of pleasure. Underlying co-constructivist emotion theories are the assumptions that the emergence of social smiling is bound to experiences of face-to-face interactions with caregivers and the impact of two developmental mechanisms--maternal and infant imitation. We analyzed mother-infant interactions from two different socio-cultural contexts and hypothesized that cross-cultural differences in face-to-face interactions determine the occurrence of both of these mechanisms and of the frequency of social smiling by 12-week-old infants. Twenty mother-infant dyads from a socio-cultural community with many face-to-face interactions (German families, Münster) were compared with 24 mother-infant dyads from a socio-cultural community with few such interactions (rural Nso families, Cameroon) when the infants were aged 6 and 12 weeks. When infants were 6 weeks old, mothers and their infants from both cultural communities smiled at each other for similar (albeit very short) amounts of time and used imitated each other's smiling similarly rarely. In contrast, when infants were 12 weeks old, mothers and their infants from Münster smiled at and imitated each other more often than did Nso mothers and their infants.

The miniaturization of expression in the development of emotional self-regulation.

This study tested an internalization model of emotional development proposing that emotional expression decreases during childhood in situations in which emotions serve only self-regulation. This model was tested by inducing joy and disappointment in solitary versus interpersonal conditions in 3 gender-matched, 20-member groups of 6-, 7-, and 8-year-olds. Results supported the model: Expression--but not self-reported feeling--decreased in solitary conditions as a function of increasing age, whereas both expression and feeling remained stable in the interpersonal condition. This effect also correlated positively with the ability to discriminate between expression and feeling on a conceptual level. Results are discussed in relation to the major developmental trend toward creating a mental level of self-regulation--first described by Vygotsky.