Rhythm in Mother‐Infant Interactions

Rhythmic behavior and the association of vocal rhythmic behavior with language development were studied in a sample of 30 mother‐infant dyads. Dyads were observed in 2 contexts (1 involved sharing pictures and the other sharing musical toys) when infants were 18 and 24 months of age. Vocal rhythmic behavior was seen in both contexts, and in both contexts mothers matched their infant's vocal rhythmic behavior at greater than chance rates. Greater matching tended to be associated with higher language scores whereas, counter to prediction, higher rates of maternal vocal rhythmic behavior tended to be associated with lower language scores. At 24 months of age, mother‐daughter dyads showed more matching than mother‐son dyads. These results suggest that differences in maternal production of vocal rhythmic behavior may foster different language learning strategies.     

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.     

Infants of Depressed Mothers Show Reduced Gaze Activity During Mother–Infant Interaction at 4 Months

Gaze is one of the main means of communication in young infants, and it has been shown to be important for subsequent socio‐emotional and cognitive development. Maternal depression is a well‐known risk factor for disrupting mother–infant interactions, but findings regarding gaze behavior in infants of depressed versus nondepressed mothers have been ambiguous. In this study, we examined gaze duration and activity in a sample of 27 infants of mothers with postpartum depression (PPD) and 49 infants of nondepressed mothers. Maternal depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale, and diagnoses were confirmed in clinical interview. Infant gaze was assessed during 4‐month face‐to‐face interactions using continuous timed‐event coding with high temporal resolution. Although we found no differences in gaze duration, infants of PPD mothers had both significantly less Gaze On and also less Gaze Off events. Findings suggest that PPD is related to reduced gaze activity during mother–infant interaction in 4‐month‐olds. This reduced activity may have long‐term negative consequences for child development.     

The Association Between Cigarette Smoking During Pregnancy and Maternal Behavior During the Neonatal Period

This study examined the association between maternal smoking during pregnancy and maternal behavior during mother‐infant interactions during the neonatal period. Participants included 84 mother‐infant dyads (43 cigarette‐exposed and 41 nonexposed) who were recruited after birth and assessed at 2 to 4 weeks of infant age. Results indicated that mothers who smoked during pregnancy had higher levels of maternal insensitivity (MI) and lower levels of maternal warmth (MW) during interactions with their infant even after controlling for demographics and pregnancy alcohol use. Maternal anxiety and hostility mediated the association between smoking and MI and maternal anger mediated the association between smoking and reduced MW. In addition, there was an interaction between infant gender and maternal smoking for MW with smokers displaying less warmth to boys during interactions.     

Mother‐ Versus Infant‐Centered Correlates of Maternal Mind‐Mindedness in the First Year of Life

We investigated whether maternal mind‐mindedness in infant–mother interaction related to aspects of obstetric history and infant temperament. Study 1, conducted with a socially diverse sample of 206 eight‐month‐old infants and their mothers, focused on links between maternal mind‐mindedness and (i) planned conception, (ii) perception of pregnancy, and (iii) recollections of first contact with the child. The two indices of mind‐mindedness (appropriate and nonattuned mind‐related comments) related to different aspects of obstetric history, but no strong associations were seen with socioeconomic status, maternal depression, or perceived social support. In Study 2, we found good temporal stability in both indices of mind‐mindedness in a sample of 41 infant–mother dyads between 3 and 7 months. Neither index of mind‐mindedness related to infant temperament. We conclude that mind‐mindedness is best characterized as a facet of the specific caregiver–child relationship, while also being influenced by stable cognitive–behavioral traits in the mother.     

Maternal Cocaine Use and Infant Behavior

This study examined the impact of maternal cocaine use and associated risk factors such as polysubstance use, maternal functioning, and caregiving on affect regulation during infancy. Participants were 45 mother‐infant dyads (19 cocaine exposed and 26 control infants) recruited at birth. Observations and maternal reports of infant behavior were obtained at 2 and 7 months of age, along with measures of pre‐ and postnatal substance use, maternal functioning, and caregiving stability. Maternal cocaine use accounted for significant variance in infant positive affect at 2 months. Other substance use and gestational age predicted infant distress to novelty and arousal during developmental assessments. At 7 months, the impact of prenatal cocaine exposure on infant affect regulation was mediated by postnatal alcohol use and caregiving stability. These findings, if replicated, suggest that 1 pathway to later problem behavior reported among substance‐exposed children may be through early regulatory problems and the quality of postnatal caregiving.     

Maternal Lifetime Trauma Exposure,Prenatal Cortisol,and Infant Negative Affectivity

Little research has examined the impact of maternal lifetime trauma exposure on infant temperament. We examined associations between maternal trauma history and infant negative affectivity and modification by prenatal cortisol exposure in a sociodemographically diverse sample of mother–infant dyads. During pregnancy, mothers completed measures of lifetime trauma exposure and current stressors. Third‐trimester cortisol output was assessed from maternal hair. When infants were 6 months old, mothers completed the Infant Behavior Questionnaire‐Revised. In analyses that controlled for infant sex and maternal age, education, race/ethnicity, and stress during pregnancy, greater maternal trauma exposure was associated with increased infant distress to limitations and sadness. Higher and lower prenatal cortisol exposure modified the magnitude and direction of association between maternal trauma history and infant rate of recovery from arousal. The association between maternal trauma history and infant distress to limitations was somewhat stronger among infants exposed to higher levels of prenatal cortisol. The analyses suggested that maternal lifetime trauma exposure is associated with several domains of infant negative affectivity independently of maternal stress exposures during pregnancy and that some of these associations may be modified by prenatal cortisol exposure. The findings have implications for understanding the intergenerational impact of trauma exposure on child developmental outcomes.     

Relation Between Maternal Contingent Responsiveness and Infant Social Expectations

This study investigated the relation between maternal contingent responsiveness and 4‐ and 5‐month‐old infants' (N = 64) social expectation behavior in a still‐face procedure. Mothers were asked to interact with their infants for 2 min (interactive phase), remain still‐faced for 1 min (still‐face phase), and resume interaction for 2 min. Mother and infant behavior was assessed for the frequency of infant and mother smiles, mother smiles that were contingent to infant smiles and infant smiles were contingent to mother smiles during the interactive phase, and infant social bids to mother during the still‐face phase. Hierarchical regression showed that mother contingent smiles during the interactive phase accounted for unique variance in infant social bids during the still‐face phase beyond that accounted for by the frequency of mother and infant smiles during the interactive phase. These results support the view that young infants' social expectations and sense of self‐efficacy are formed within their interactions with their caregivers.     

The Interplay Between Tonal Synchrony and Social Engagement in Mother–Infant Interaction

This study explores the relationship between tonal synchrony and maternal‐infant social engagement based on free‐play recordings of 15 mothers and their 3‐month‐old infants in a laboratory setting. Moment‐by‐moment analyses on a microlevel were used to study social engagement and vocal interaction. We analysed and categorized 854 vocalization periods (mother‐only vocalizations, tonal interaction periods, nontonal interaction periods, and mutual silence). Tonal synchrony was analysed in terms of harmonic and pentatonic series based on pitch frequency analyses. Social engagement was microanalyzed in terms of matched and mismatched engagement states. ANOVA‐repeated measures revealed, most importantly, a significant relationship between TIPs and social interaction repair, which indicates the importance of tonal synchrony in the flow of social engagement in mother–infant dyads. Other significant relationships were found between (a) nTIPs/mismatch–mismatch, and, (b) MOV/affect loss. As mentioned in the discussion, the findings are suggestive for clinical applications (e.g., music therapy) and warrant further research.     

Does Child Sex Moderate Vulnerability to Postpartum Risk among Infants of Mothers at Risk for Psychopathology?

Early childhood behavior problems may indicate risk for subsequent psychopathology (Shaw, Gilliom, Ingoldsby, & Nagin, Developmental Psychology, 39, 2003, 189). There is some evidence to suggest that boys and girls may be differentially susceptible to postpartum risk factors that predict problem behaviors in early childhood (Kochanska, Coy, & Murray, Child Development, 72, 2001, 1091; Martel, Klump, Nigg, Breedlove, & Sisk, Hormones and Behavior , 55, 2009, 465). The main aim of this study is to examine whether child sex moderates the effect of infant and maternal predictors of toddler problem behaviors in a unique sample of high‐risk mother–child dyads. Analyses were based on data collected for 198 mother–child dyads (52% male offspring) followed longitudinally from birth to 18 months. Maternal and infant variables, including maternal PTSD and depression symptoms, maternal maltreatment history, observed maternal parenting quality, demographic risk, and infant negative emotionality and night waking, were used to predict toddler behavior problems. Although boys and girls displayed similar levels of total problem behaviors at 18 months overall, the specific set of infant and maternal variables that predicted toddler problems varied by child sex. The significant predictor for boys was maternal PTSD symptoms, whereas significant predictors for girls were infant negative emotionality and sleep problems. Results suggest that sex‐differentiated transmission of risk can be identified as early as 18 months postpartum. These differences suggest a gender‐specific biological sensitivity to maternal psychopathology, or alternatively, a gender‐specific reporting bias among mothers with childhood maltreatment histories.     

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.     

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.     

Mother–Infant Interaction and Child Brain Morphology: A Multidimensional Approach to Maternal Sensitivity

Emerging research suggests that normative variation in parenting quality relates to children's brain development. However, although the young brain is presumed to be especially sensitive to environmental influence, to our knowledge only two studies have examined parenting quality with infants as it relates to indicators of brain development, and both were cross‐sectional. This longitudinal study investigated whether different components of maternal sensitivity in infancy predicted the volume of two brain structures presumed to be particularly sensitive to early experience, namely the amygdala and the hippocampus. Three dimensions of sensitivity (Cooperation/Attunement, Positivity, Accessibility/Availability) were observed in 33 mother–infant dyads at 1 year of age and children underwent structural magnetic resonance imaging at age 10. Higher maternal Accessibility/Availability during mother–infant interactions was found to be predictive of smaller right amygdala volume, while greater maternal positivity was predictive of smaller bilateral hippocampal volumes. These longitudinal findings extend those of previous cross‐sectional studies and suggest that a multidimensional approach to maternal behavior could be a fruitful way to further advance research in this area, given that different facets of parenting might be differentially predictive of distinct aspects of neurodevelopment.     

Delivery Pain and the Development of Mother—Infant Interaction

This study examined delivery pain as a possible risk factor for the development of mother‐infant interaction. Eighty‐one mothers completed the Pain Catastrophizing Scale, the State‐Trait Anxiety Inventory, and the Edinburgh Postnatal Depression Scale. A retrospective evaluation of labor pain was performed using the Visual Analog Scale at 2 days postpartum. Six weeks after birth the mothers were visited at home, completed measures of anxiety and depression, and were observed during a free play session with the infant. The mother's tendency to catastrophize pain predicted lower levels of mother‐infant reciprocity at 6 weeks, controlling for maternal age, education, parity, epidural analgesia, pain perception, anxiety, and depression. Trait anxiety was related to lower maternal sensitivity. The mother's tendency to catastrophize pain was discussed in relation to the personality trait of exaggerated emotional perception of pain and its potential interference with the formation of the mother‐infant relationship.     

Maternal Mentalization and Behavior Under Stressful Contexts: The Moderating Roles of Prematurity and Household Chaos

This study examines the links between online maternal mentalization during mother–infant interaction, maternal sensitivity, and family triadic interaction while considering the cumulative role of two stressful contexts (cumulative stressful contexts): premature birth (a child‐driven stressful context) and household chaos (an environment‐driven stressful context). Two moderation models were tested on a sample of 134 families with 6‐month‐old infants (77 low‐risk preterm, 57 full‐term). Cumulative stressful contexts mitigated the relations between maternal mentalization and behavior, such that online maternal mentalization during mother–infant interaction was related to both maternal sensitivity and the quality of family triadic interaction under low cumulative stressful contexts, but not under high cumulative stressful contexts. Implications for understanding the influence of online maternal mentalization on maternal sensitivity and the family triad are discussed.     

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.     

Prenatal Reflective Functioning and Accumulated Risk as Predictors of Maternal Interactive Behavior During Free Play,the Still‐Face Paradigm,and Two Teaching Tasks

This study examined whether prenatal reflective functioning (RF) was related to mothers’ interactive style across contexts with their 6‐month‐old infants (M age = 6.02 months, SD = 0.41, 54% boys), and to what extent quality of prenatal RF could account for the influence of accumulated risk on maternal interactive behavior. Accumulated risk was defined as the sum‐score of a selection of risk factors that have been associated with suboptimal infant development. Mother–infant dyads (N = 133) were observed during free play, two teaching tasks, and the Still‐Face Paradigm (SFP). Better prenatal RF was associated with more positive maternal behavior in all settings and less negative behavior during teaching and SFP reengagement. Accumulated risk and prenatal RF predicted shared variance in maternal interactive behavior (with unique predictive effects observed only for RF on sensitivity during teaching and SFP play, and for accumulated risk on sensitivity and positive engagement during SFP play, and internalizing‐helplessness during SFP reengagement). Accumulated risk had an indirect effect on maternal sensitivity during teaching and SFP play through prenatal RF. These findings suggest not only that RF may be targeted prenatally to improve mother–infant interactions, but also that enhancing RF skills may ameliorate some of the negative consequences from more stable perinatal risk factors that influence parent–child interactions.     

Longitudinal links between maternal factors and infant cognition: Moderation by infant sleep

The current study examined the moderating role of infant sleep in the link between maternal factors (i.e., maternal education, depressive symptoms, sleep disturbance) and infant cognition. Data come from 95 African American parent–child dyads. At 3 months of age, infant sleep was objectively measured using videosomnography and actigraphy, from which measures of sleep regulation and consolidation were calculated. Mothers also self‐reported their level of education, depressive symptoms, and sleep quality. At 6 months of age, infants completed cognitive assessments, including a measure of general cognitive ability and observed attention behavior. Findings revealed that infant sleep quality interacted with maternal education and sleep disturbances to predict cognition. Specifically, the link between maternal education and infants’ attention behavior was significant and positive for infants with better regulated sleep, but not for infants with poorly regulated sleep. Similarly, the link between maternal sleep disturbance and infant cognition depended on infant sleep quality. For infants with poorer sleep consolidation, increased maternal sleep disturbance predicted poorer infant general cognitive ability. For infants with better sleep consolidation, maternal sleep disturbance was positively related to both general cognitive ability and attention behavior. These findings suggest that infant sleep quality moderates the impact of environmental factors on cognitive functioning.     

Distinguishing Mother–Infant Interaction From Stranger–Infant Interaction at 2, 4, and 6 Months of Age

Observers watched videotaped face‐to‐face mother–infant and stranger–infant interactions of 12 infants at 2, 4, or 6 months of age. Half of the observers saw each mother paired with her own infant and another infant of the same age (mother tapes) and half saw each infant paired with his or her mother and with a stranger (infant tapes). Observers were asked to judge which was the mother–infant dyad in each pair. Observers' accuracy improved as infants aged and was above chance for both mother and infant tapes when infants were 6 months. Differences between mother–infant and stranger–infant dyadic communication patterns also emerged as the infants aged. At 6 months, mother–infant dyads had more symmetrical communication and less asymmetrical communication than stranger–infant dyads.     

Infant‐Directed Speech Is Modulated by Infant Feedback

When mothers engage in infant‐directed (ID) speech, their voices change in a number of characteristic ways, including adopting a higher overall pitch. Studies have examined these acoustical cues and have tested infants' preferences for ID speech. However, little is known about how these cues change with maternal sensitivity to infant feedback in the context of interaction. In this study, each mother watched her infant (located in an adjacent sound booth) on a video screen and talked to him or her through a microphone. The mother believed that her infant could hear her voice and she attempted to make her infant happy through her vocalizations. In reality, the infant could not hear her voice. The mother's ID speech was analyzed in real time for changes in mean pitch. For half of the infant–mother dyads an experimenter surreptitiously positively engaged the infant when the voice analysis revealed a rise in pitch, thereby producing positive reinforcement to the mother for natural higher pitched ID speech. The other half were reinforced for lower pitched ID speech. Mothers raised their pitch significantly more in the former than the latter condition, illustrating that the pitch of ID speech is dynamically affected by feedback from the infant.