Persistent symptoms of maternal post-traumatic stress following childbirth across the first months postpartum: Associations with perturbations in maternal behavior and infant avoidance of social gaze toward mother

Recent literature identifies childbirth as a potentially traumatic event, following which mothers may develop symptoms of Post-Traumatic-Stress-Following-Childbirth (PTS-FC). The current study examines whether stable symptoms of PTS-FC during the early postpartum period may impose risk for perturbations in maternal behavior and infant social-engagement with mother, controlling for comorbid postpartum internalizing symptoms. Mother-infant dyads (N = 192) were recruited from the general population, during the third trimester of pregnancy. 49.5% of the mothers were primipara, and 48.4% of the infants were girls. Maternal PTS-FC was assessed at 3-day, 1-month and 4-month postpartum, via self-report and clinician-administered interview. Latent Profile Analysis generated two profiles of symptomology: “Stable-High-PTS-FC” (17.0%), and “Stable-Low-PTS-FC” (83%). Membership in the “Stable-High-PTS-FC” profile associated with perturbed maternal sensitivity, which was in turn significantly associated with infant avoidance of social gaze toward mother (Indirect effect β = −0.15). Results suggest the need for early screening and inform the planning of early preventive interventions.     

Patterns of positivity: Positive affect trajectories among infants of mothers with a history of depression

This study examined positive affect (PA) trajectories over the first year of life among infants of mothers with a history of depression (N = 191) as well as predictors (i.e., maternal prenatal and postpartum depression symptoms, maternal parenting behaviors) of those trajectories. Infant PA was observed in play and feeding tasks during laboratory visits at 3, 6, and 12 months of age; parenting behaviors were observed at 3 months. Mothers completed questionnaires regarding their symptoms of depression throughout the prenatal period and during the first 3 months postpartum. Growth curve analyses indicated that infant PA increased across time, and this finding replicated across both the play and feeding tasks, though increases slowed over time. Neither maternal prenatal nor postpartum depression symptoms predicted infants' PA trajectories, but mothers' PA, positive parenting, and disengaged parenting were associated with infant PA during the play task. Our finding that infant PA increased over the first year postpartum suggests PA trajectories among infants of mothers with a history of depression may be indices of resilience, despite risks associated with their mothers' history of depression. Furthermore, this study highlights parenting behaviors that may be important targets of prevention and early intervention efforts to bolster infant PA.     

Effects of Maternal Responsiveness on Infant Responsiveness and Behavior in the Still‐Face Task

The effects of maternal responsiveness on infant responsiveness and behavior in the Still‐Face Task were longitudinally examined through infants' first 3 months. Maternal vocal responsiveness and infant vocal and smiling responsiveness significantly increased when infants were 2 months of age. Mothers showed continuity of individual differences in vocal responsiveness from the infants' newborn period. Maternal responsiveness predicted infant responsiveness within and across sessions. Compared with infants with low‐responsive mothers, infants with high‐responsive mothers were more attentive and affectively engaged during the Still‐Face Task from 1 month of age. Infants with high‐responsive mothers discriminated between the task phases with their smiling at 1 month, a month before infants with low‐responsive mothers did so. Infants in both groups discriminated between the phases with their attention and nondistress vocalizations throughout their first 3 months. Results suggest that maternal responsiveness influences infant responsiveness and facilitates infants' engagement and expectations for social interaction.     

Maternal Postpartum Depression Increases Vulnerability for Toddler Behavior Problems through Infant Cortisol Reactivity

The current study examined the role of hypothalamic‐pituitary‐adrenal reactivity (a physiological indicator of stress) in early infancy as a mediator of the relationship between maternal postpartum depression and toddler behavior problems. Participants were 137 at‐risk mothers and their children participating in a longitudinal study of intergenerational transmission of risk. Mothers’ depression was measured five times during the infants’ first 18 months. Infant cortisol was collected during a social stressor (the still‐face paradigm) when infants were 6 months old, and mothers reported on toddlers’ internalizing and externalizing symptoms at 18 months. Among this sample of high‐risk mother–infant dyads, early postpartum depression predicted atypical infant cortisol reactivity at 6 months, which mediated the effect of maternal depression on increased toddler behavior problems. Clinical implications are discussed.     

Infant Sex Moderates the Effects of Maternal Pre‐ and Postnatal Stress on Executive Functioning at 8 Months of Age

Previous studies report that early life stress, including maternal pre‐ and postnatal stress, has adverse effects on cognitive development and that these associations might be sex‐specific. However, no studies exist on early life stress and infant executive functioning (EF). The aim of this study was to examine the relationship between maternal pre‐ and postnatal stress and infant EF, and whether these associations are moderated by infant sex. Maternal prenatal depressive, general anxiety, and pregnancy‐specific anxiety symptoms were measured three times, and postnatal depressive and general anxiety symptoms were measured 6 months postpartum. Infant EF was assessed with a modified A‐not‐B task 8 months postpartum (N = 214). Maternal postnatal general anxiety predicted poorer EF in girls in comparison with boys. Moreover, there was a trend toward an interaction between prenatal anxiety and infant sex such that prenatal anxiety predicted infant EF differently in girls and in boys. No association was found between depressive symptoms or pregnancy‐specific anxiety symptoms and infant EF. These findings suggest that maternal anxiety may have sex‐specific effects on early EF and that pre‐ and postnatal stress may differently affect infant EF/cognitive development. The implications of these findings and important future directions are discussed.     

Exploring the relation between maternal mind‐mindedness and children’s symbolic play: A longitudinal study from 6 to 18 months

Relations between mothers’ mind‐mindedness (appropriate attunement to their infants’ internal states) at 6 and 12 months and infants’ early symbolic play during infant–mother pretense at 12 and 18 months were investigated in a sample of 43 mothers and infants. Mothers’ appropriate mind‐related comments were associated with average level, length, complexity, and maturity level of symbolic play. Specific sub‐categories of appropriate mind‐related comments were identified as independent predictors of children's symbolic play. Appropriate comments about desires and cognitions at 6 months were associated with average level and length of episodes, as well as with maturity level of symbolic play at 12 months. Longitudinal stability in the appropriateness and content of mothers’ mind‐related comments was also investigated. The results are discussed in terms of the proposal that attunement to specific types of internal state should vary as a function of infant age in order to index mind‐mindedness.     

Age‐Related Changes in Prosodic Features of Maternal Speech to Prelingually Deaf Infants with Cochlear Implants

This study investigated prosodic and structural characteristics of infant‐directed speech to hearing‐impaired infants as they gain hearing experience with a cochlear implant over a 12‐month period of time. Mothers were recorded during a play interaction with their HI infants (N = 27, mean age 18.4 months) at 3, 6, and 12 months postimplantation. Two separate control groups of mothers with age‐matched normal‐hearing infants (NH‐AM) (N = 21, mean age 18.1 months) and hearing experience‐matched normal‐hearing infants (NH‐EM) (N = 24, mean age 3.1 months) were recorded at three testing sessions. Mothers produced less exaggerated pitch characteristics, a larger number of syllables per utterance, and faster speaking rate when interacting with NH‐AM as compared to HI infants. Mothers also produced more syllables and demonstrated a trend suggesting faster speaking rate in speech to NH‐EM relative to HI infants. Age‐related modifications included decreased pitch standard deviation and increased number of syllables in speech to NH‐AM infants and increased number of syllables in speech to HI and NH‐EM infants across the 12‐month period. These results suggest that mothers are sensitive to the hearing status of their infants and modify characteristics of infant‐directed speech over time.     

Prenatal Maternal Anxiety and Depression Predict Negative Behavioral Reactivity in Infancy

The effects of maternal antenatal and postnatal anxiety and depression on infant negative behavioral reactivity were examined in a sample of 22 mother‐infant pairs. Maternal anxiety and depression were assessed by standardized measures during the third trimester of pregnancy and postpartum. Infant negative behavioral responses to novelty were assessed using a previously validated measure at 4 months of age. Maternal anxiety and depression during the prenatal, but not the postnatal period, were related to infant negative behavioral reactivity to novelty. These data illustrate that prenatal maternal psychological state can exert persisting influences on human infant behavior.     

A Comparative Study of Arm‐Restraint Methodology: Differential Effects of Mother and Stranger Restrainers on Infants' Distress Reactivity at 6 and 9 Months of Age

This study examined both differential patterns and the stability of infants' (N = 70) distress reactivity across mother and stranger arm‐restraint conditions when infants were 6 and 9 months of age. Reactivity measures included observational variables for the rise, intensity, and duration of infant distress as well as motor activities associated with escape behaviors. Correlation analyses revealed that infant behaviors during arm restraint were modestly stable across conditions and over time; however, mean comparisons also showed that infants' distress responses appear to be sensitive to protocol parameters (whether restrainer is mother or stranger). At 6 months of age, infants cried more during maternal restraint than with strangers and exhibited escape behaviors more frequently with mothers. Findings further indicate that infants' distress reactivity undergoes developmental alterations from 6 to 9 months of age, with infants crying more quickly, reaching peak intensity of distress faster, and displaying more distress at 9 months compared to 6 months. These changes in infants' reactivity were particularly accentuated during maternal compared to stranger restraint conditions at 9 months of age.     

Early psychosocial risk factors and postnatal parental reflective functioning

Psychosocial factors have been found to relate to parental reflective functioning (PRF), a parent's ability to mentalize about themselves and their child. Relations between maternal psychosocial risk factors and PRF were investigated in a community sample. A sample of mothers (n = 146) was assessed for risk factors when infants were 6 months, infant temperament was assessed using an observational measure, and PRF was assessed with the Parent Development Interview-Revised (PDI). PRF was measured again with the Parental Reflective Functioning Questionnaire (PRFQ) when children were 4 years (n = 105) and 5 years (n = 92), with an additional sample of mothers (n = 48) tested at these two timepoints. Results showed that in infancy, total maternal psychosocial risk related to lower PDI-PRF; regression analyses highlighted low socioeconomic status, unplanned pregnancy, and low maternal anxiety as independent predictors of lower PDI-PRF. PDI-PRF scores at 6 months did not relate to PRFQ scores, but PRFQ subscales showed stability over time from age 4–5. Results are discussed with regard to the impact of maternal psychosocial risk and infant temperament on PRF and the stability and concordance of PRF measures.     

Correlates of infant pointing frequency in the first year

This study examines the emergence of concurrent correlates of infant pointing frequency with the aim of contributing to its ontogenetic theories. We measured monthly from 8 to 12 months infants' (N = 56) index-finger pointing frequency along with several candidate correlates: (1) family socioeconomic status (SES), (2) mothers' pointing production, and (3) infants' point following to targets in front of and behind them. Results revealed that (1) infants increased their pointing frequency across age, but high-SES infants had a steeper increase, and a higher pointing frequency than low-SES infants from 10 months onward, (2) maternal pointing frequency was not associated with infant pointing frequency at any age, (3) infants' point following abilities to targets behind their visual fields was positively associated with their pointing frequency at 12 months, after pointing had already emerged around 10 months. Findings suggest that family SES impacts infants' pointing development more generally, not just through maternal pointing. The association between pointing and following points to targets behind, but not in front, suggests that a higher level of referential understanding emerges after, and perhaps through the production of pointing.     

Predisposing Factors for Elevated Restricted and Repetitive Behavior in Typically Developing Toddlers

Little is known about the relation between levels of restricted and repetitive behavior (RRB) in infants and parent factors. The present study investigated maternal and psychosocial factors (depressive symptoms, socio‐economic status, social support) and mother–infant engagement factors (mind‐mindedness, sensitivity, and infant–mother attachment security) as predictors of children's RRB at age 26 months in a sample of 206 mothers and children. Maternal depressive symptoms predicted levels of sensory and motor repetitive behavior and rigid, routinized, and ritualistic repetitive behavior. Lower socioeconomic status also predicted independent variance in children's sensory and motor repetitive behavior. The relations between maternal depressive symptoms and both types of RRB were not mediated through observational measures of maternal sensitivity or mind‐mindedness at 8 months, or attachment security at 15 months. The results are discussed in terms of whether stress regulation, self‐stimulation, and genetic susceptibility can help explain the observed link between maternal depressive symptoms and RRB in the child.     

Infant Behavior and Competence Following Prenatal Exposure to a Natural Disaster: The QF2011 Queensland Flood Study

This study utilized a natural disaster to investigate the effects of prenatal maternal stress (PNMS) arising from exposure to a severe flood on maternally reported infant social–emotional and behavioral outcomes at 16 months, along with potential moderation by infant sex and gestational timing of flood exposure. Women pregnant during the Queensland floods in January 2011 completed measures of flood‐related objective hardship and posttraumatic stress (PTS). At 16 months postpartum, mothers completed measures describing depressive symptoms and infant social–emotional and behavioral problems (n = 123) and competence (n = 125). Greater maternal PTS symptoms were associated with reduced infant competence. A sex difference in infant behavioral problems emerged at higher levels of maternal objective hardship and PTS; boys had significantly more behavioral problems than girls. Additionally, greater PTS was associated with more behavioral problems in boys; however, this effect was attenuated by adjustment for maternal depressive symptoms. No main effects or interactions with gestational timing were found. Findings highlight specificity in the relationships between PNMS components and infant outcomes and demonstrate that the effects of PNMS exposure on behavior may be evident as early as infancy. Implications for the support of families exposed to a natural disaster during pregnancy are discussed.     

Development of Infant Pointing from 10 to 12 months: The Role of Relevant Caregiver Responsiveness

Infants’ pointing frequency is a predictor of their later language abilities. Yet, predictors of pointing frequency in the first year of life are not well understood. Study 1 explored what factors in infants and caregivers at 10 months would predict the pointing frequency of infants at 12 months (N = 35). Infant‐driven predictors were infants’ fine‐motor skills and point‐following abilities. Caregiver‐mediated predictors were caregivers’ pointing frequency and responsiveness toward infants’ pointing. Relevant caregiver responsiveness at 10 months predicted infants’ pointing frequency at 12 months, controlling for the other factors and infants’ prior pointing frequency. Study 2 explored whether child‐level factors influence caregivers’ responsiveness (N = 49). We examined the hand shape of infants’ pointing (whole‐hand versus index‐finger) and the presence of point‐accompanying vocalizations. Infants’ vocalization‐accompanied points were more likely to elicit relevant responses from caregivers, while hand shapes played a less pronounced role. Together, the findings reveal an early emerging mutual relationship between infant pointing and caregiver behavior such that certain characteristics of infant pointing predict caregivers’ responsiveness, and relevant responsiveness toward infants’ pointing predicts the increase in infants’ pointing frequencies.     

Anger and Positive Reactivity in Infancy: Effects on Maternal Report of Surgency and Attention Focusing in Early Childhood

We examined two aspects of temperamental approach in early infancy, positive reactivity and anger, and their unique and combined influences on maternal reports of child surgency and attention focusing at 4 years of age. One hundred and fourteen infants were observed for their positive reactions to novel stimuli at 4 months, and their anger expressions during arm restraint at 9 months. Child surgency and attention focusing at age 4 years were assessed by maternal report. Infants who expressed more anger to restraint were rated higher in surgency during early childhood relative to infants who expressed less anger. The effects of positive reactivity to novelty on attention focusing were moderated by anger to restraint. These findings suggest that infant temperamental approach tendencies are multifaceted and have both unique and combined influences on later maternal report of attention and social behavior.     

Maternal Responsiveness and the Development of Directed Vocalizing in Social Interactions

For effective communication, infants must develop the phonology of sounds and the ability to use vocalizations in social interactions. Few studies have examined the development of the pragmatic use of prelinguistic vocalizations, possibly because gestures are considered hallmarks of early pragmatic skill. The current study investigated infant vocal production and maternal responsiveness to examine the relationship between infant and maternal behavior in the development of infants' vocal communication. Specifically, we asked whether maternal responses to vocalizations could influence the development of prelinguistic vocal usage, as has been documented in recent experimental studies exploring the relation between maternal responses and phonological development. Twelve mother–infant dyads participated over a six‐month period (between 8 and 14 months of age). Mothers completed the MacArthur Communicative Development Inventory when infants were 15 months old. Maternal sensitive responses to infant vocalizations in the previous months predicted infants' mother‐directed vocalizations in the following months, rather than overall response rate. Furthermore, mothers' sensitive responding to mother‐directed vocalizations was correlated with an increase in developmentally advanced, consonant–vowel vocalizations and some language measures. This is the first study to document a social shaping mechanism influencing developmental change in pragmatic usage of vocalizations in addition to identifying the specific behaviors underlying development.     

Infant regulation during the pandemic: Associations with maternal response to the COVID-19 pandemic,well-being,and socio-emotional investment

In the transition to parenthood, the COVID-19 pandemic poses an additional strain on parental well-being. Confirmed infections or having to quarantine, as well as public health measures negatively affect parents and infants. Contrary to previous studies mainly focusing on the well-being of school-aged children and their parents during lockdown periods, the present study investigated how mothers of infants respond to the COVID-19 pandemic and whether this is related to maternal well-being, maternal socio-emotional investment, and infant regulation. Between April and June 2021, 206 mothers of infants (M_age = 7.14 months, SD_age = 3.75 months) reported on COVID-19 infections, their response to the COVID-19 pandemic, their well-being, socio-emotional investment, and their infant’s regulation. Exploratory factor analyses yielded five dimensions of maternal response to the COVID-19 pandemic: social distancing, worrying about the child, birth anxiety, distancing from the child, and information on COVID-19-related parenting behavior and support. These dimensions were related to mother-reported infant regulatory problems. Path analyses revealed paths via reduced maternal well-being and maternal socio-emotional investment. Maternal perceptions of infant regulatory problems are related to how the mothers respond to the COVID-19 pandemic. Better information about COVID-19-related parenting behavior and support might buffer against these effects.     

Neural mechanisms of language development in infancy

Understanding the neural processes underpinning individual differences in early language development is of increasing interest, as it is known to vary in typical development and to be quite heterogeneous in neurodevelopmental conditions. However, few studies to date have tested whether early brain measures are indicative of the developmental trajectory of language, as opposed to language outcomes at specific ages. We combined recordings from two longitudinal studies, including typically developing infants without a family history of autism, and infants with increased likelihood of developing autism (infant-siblings) (N = 191). Electroencephalograms (EEG) were recorded at 6 months, and behavioral assessments at 6, 12, 18, 24 and 36 months of age. Using a growth curve model, we tested whether absolute EEG spectral power at 6 months was associated with concurrent language abilities, and developmental change in language between 6 and 36 months. We found evidence of an association between 6-month alpha-band power and concurrent, but not developmental change in, expressive language ability in both infant-siblings and control infants. The observed association between 6-month alpha-band power and 6-month expressive language was not moderated by group status, suggesting some continuity in neural mechanisms.     

Temperamental Susceptibility to Parenting among Preterm and Full‐Term Infants in Early Cognitive Development

The current study examined the interaction between premature birth, temperamental reactivity, and parenting in early cognitive development. Participants were 142 infants (80 preterm; 62 full term) and their parents. Parent–child interactions (maternal, paternal, and co‐parental) were observed at age 6 months to assess parental structuring behaviors. Additionally, both parents reported on infants' temperamental reactivity. At 12 months of age, infants' cognitive abilities were assessed. Consistent with the diathesis–stress model, preterm infants had lower cognitive outcomes than full‐term infants when exposed to low levels of co‐parental structuring, but functioned similarly when exposed to high levels of co‐parental structuring. However, temperamental reactivity moderated this effect: Infants who carried one susceptibility factor (i.e., premature birth or reactive temperament) were similarly affected by co‐parental structuring, whereas infants who carried two or no susceptibility factors were not. Furthermore, consistent with the differential susceptibility hypothesis, infants with highly reactive temperaments had lower cognitive functioning when exposed to low maternal structuring, but higher cognitive functioning when exposed to high maternal structuring compared to infants with lower reactivity. Results from this study highlight the importance of considering both temperamental reactivity and quality of parenting in understanding preterm infants' early cognitive vulnerability.     

Development of Vocal Protests From 3 to 18 Months

Infants often protest the activities of their caregivers, and this particular social interaction may provide an important window on early communication and its development. This study used naturalistic methods to investigate the development of vocal protests. Fifteen mother‐infant dyads at each of 5 ages, from 3 to 18 months, were observed at home. Maternal behaviors of caregiving and prohibiting were tallied from videotapes, as were infants' protests of these behaviors. Maternal caregiving decreased with age, but maternal prohibitions increased. There were no changes over age in the probability of protesting maternal caregiving behavior; however, 12‐month‐olds were more likely to protest prohibitions than 6‐ or 8‐month‐olds. Older infants were also more likely to use intense protests, such as screams, than younger infants. These age‐related changes were mirrored by the differences in prohibitions and protests observed between 8‐month‐olds who could crawl and those who could not. Findings from this study were related to previous research on infant crying as an important part of the prelinguistic communication system.