The Regulation of Infant Negative Emotions: The Role of Maternal Sensitivity and Infant‐Directed Speech Prosody

This study explored the role of maternal sensitivity and infant‐directed speech (IDS) prosody in infants’ expression and regulation of negative emotion. Seventy mothers and their 3‐month‐old infants were observed during the Still‐Face Paradigm (SFP). Maternal sensitivity and IDS prosody were assessed at baseline and infant negative affect in the baseline, still‐face, and reunion episodes. Results showed that prototypical IDS prosody characterized by wider fundamental frequency (F0) variability was related to decreases in infant's negative affect, but only if accompanied by maternal sensitivity. Infants of sensitive mothers who spoke with more prototypical IDS prosody showed better abilities to regulate negative affect during the SFP. When prototypical IDS prosody was accompanied by low maternal sensitivity, infants showed lower regulation of negative emotions. In conclusion, infant negative affect regulation in a dyadic setting is facilitated by an optimal combination of both more prototypical maternal IDS prosody and maternal sensitive responsiveness. Implications for the study of mother–infant interaction are discussed.     

Infant‐Directed Speech Facilitates Word Segmentation

There are reasons to believe that infant‐directed (ID) speech may make language acquisition easier for infants. However, the effects of ID speech on infants' learning remain poorly understood. The experiments reported here assess whether ID speech facilitates word segmentation from fluent speech. One group of infants heard a set of nonsense sentences spoken with intonation contours characteristic of adult‐directed (AD) speech, and the other group heard the same sentences spoken with intonation contours characteristic of ID speech. In both cases, the only cue to word boundaries was the statistical structure of the speech. Infants were able to distinguish words from syllable sequences spanning word boundaries after exposure to ID speech but not after hearing AD speech. These results suggest that ID speech facilitates word segmentation and may be useful for other aspects of language acquisition as well. Issues of direction of preference in preferential listening paradigms are also considered.     

Role of Clinical Diagnosis and Medication Use in Effects of Maternal Depression on Infant‐Directed Speech

Infant‐directed (ID) speech was recorded from mothers as they interacted with their 4‐ to 12‐month‐old infants. Hierarchical regression analyses revealed that two variables, age of the mother and mother's diagnosed depression, independently accounted for significant proportions of the variance in the extent of change in fundamental frequency (ΔF0). Specifically, depressed mothers produced ID speech with smaller ΔF0 than did nondepressed mothers, and older mothers produced ID speech with larger ΔF0 than did younger mothers. Mothers who were taking antidepressant medication and who were diagnosed as being in at least partial remission produced ID speech with mean ΔF0 values that were comparable to those of nondepressed mothers. These results demonstrate explicit associations between major depressive disorder and an acoustic attribute of ID speech that is highly salient to young infants.     

Face Preferences for Infant‐ and Adult‐Directed Speakers in Infants of Depressed and Nondepressed Mothers: Association with Infant Cognitive Development

Face preferences for speakers of infant‐directed and adult‐directed speech (IDS and ADS) were investigated in 4‐ to 13.5‐month‐old infants of depressed and nondepressed mothers. Following 1 min of exposure to an ID or AD speaker (order counterbalanced), infants had an immediate paired‐comparison test with a still, silent image of the familiarized versus a novel face. In the test phase, ID face preference ratios were significantly lower in infants of depressed than nondepressed mothers. Infants' ID face preference ratios, but not AD face preference ratios, correlated with their percentile scores on the cognitive (Cog) scale of the Bayley Scales of Infant & Toddler Development (3rd Edition; BSID‐III), assessed concurrently. Regression analyses revealed that infant ID face preferences significantly predicted infant Cog percentiles even after demographic risk factors and maternal depression had been controlled. Infants may use IDS to select social partners who are likely to support and facilitate cognitive development.     

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.     

Influences of Infant‐Directed Speech on Early Word Recognition

When addressing infants, many adults adopt a particular type of speech, known as infant‐directed speech (IDS). IDS is characterized by exaggerated intonation, as well as reduced speech rate, shorter utterance duration, and grammatical simplification. It is commonly asserted that IDS serves in part to facilitate language learning. Although intuitively appealing, direct empirical tests of this claim are surprisingly scarce. Additionally, studies that have examined associations between IDS and language learning have measured learning within a single laboratory session rather than the type of long‐term storage of information necessary for word learning. In this study, 7‐ and 8‐month‐old infants' long‐term memory for words was assessed when words were spoken in IDS and adult‐directed speech (ADS). Word recognition over the long term was successful for words introduced in IDS, but not for those introduced in ADS, regardless of the register in which recognition stimuli were produced. Findings are discussed in the context of the influence of particular input styles on emergent word knowledge in prelexical infants.     

Age‐Specific Preferences for Infant‐Directed Affective Intent

This study examined the developmental course of infants' attentional preferences for 3 types of infant‐directed affective intent, which have been shown to be commonly used at particular ages in the first year of life. Specifically, Kitamura and Burnham (2003) found mothers' tone of voice in infant‐directed speech is most comforting between birth and 3 months, most approving at 6 months, and most directive at 9 months. Thus, the aim of this study was to assess whether there is a relation between the type of affective intent used by mothers at each age point, and infants' affective intent preferences. Each infant group, 3‐, 6‐, and 9‐month‐olds, was played the 3 types of affective intent alternating across a single test session. When analyzed across age, the interactions revealed the predicted developmental trajectory; that is, infant preferences transformed between 3 and 6 months from comforting to approving, and between 6 and 9 months, from approving to directive. However, when analyzed separately by age, it was shown that 3‐month‐olds preferred comforting to other types; 6‐month‐olds preferred approving to directive, but listened equally to approving and comforting; and 9‐month‐olds showed no preference for any type of affective intent. Because it was possible that 9‐month‐olds were more focused on phonetic and phonotactic information, a new group of 9‐month‐olds was tested with intonation‐only versions of the 3 affective intent types. Under these conditions, they were found to prefer directive to comforting, but not directive to approving types. The results of this study have implications for what infants pay attention to in their social and linguistic environment over the course of the first year.     

Infant Preferences for Structural and Prosodic Properties of Infant‐Directed Speech in the Second Year of Life

While a large literature discusses young infants' preference for an infant‐directed speaking style, few studies have explored preferences after the first year. The present work compares infants' preference for two different properties of IDS speech: prosodic changes (primarily pitch and pitch variability) and structural properties (utterance length; lexical repetition). We found that both 12‐ and 16‐month‐old infants continued to prefer listening to speech with the prosodic properties of IDS, but neither age showed any preference for speech with the lexical repetition and short utterances typical of IDS.     

Infant‐Directed Prosody Helps Infants Map Sounds to Meanings

Adults typically use an exaggerated, distinctive speaking style when addressing infants. However, the effects of infant‐directed (ID) speech on infants' learning are not yet well understood. This research investigates how ID speech affects how infants perform a key function in language acquisition, associating the sounds of words with their meanings. Seventeen‐month‐old infants were presented with two label‐object pairs in a habituation‐based word learning task. In Experiment 1, the labels were produced in adult‐directed (AD) speech. In Experiment 2, the labels were produced in ID prosody; they had higher pitch, greater pitch variation, and longer durations than the AD labels. We found that infants failed to learn the labels in AD speech, but succeeded in learning the same labels when they were produced in ID speech. Experiment 3 investigated the role of variability in learning from ID speech. When the labels were presented in ID prosody with no variation across tokens, infants failed to learn them. Our findings indicate that ID prosody can affect how readily infants map sounds to meanings and that the variability in prosody that is characteristic of ID speech may play a key role in its effect on learning new words.     

Changes in Preference for Infant‐Directed Speech in Low and Moderate Noise by 4.5‐ to 13‐Month‐Olds

Although a large literature discusses infants' preference for infant‐directed speech (IDS), few studies have examined how this preference might change over time or across listening situations. The work reported here compares infants' preference for IDS while listening in a quiet versus a noisy environment, and across 3 points in development: 4.5 months of age, 9 months of age, and 13 months of age. Several studies have suggested that IDS might help infants to pick out speech in the context of noise (Colombo, Frick, Ryther, Coldren, & Mitchell, 1995; Fernald, 1984; Newman, 2003); this might suggest that infants' preference for IDS would increase in these settings. However, this was not found to be the case; at all 3 ages, infants showed similar advantage (or lack thereof) for IDS as compared to adult‐directed speech when presented in noise versus silence. There was, however, a significant interaction across ages: Infants aged 4.5 months showed an overall preference for IDS, whereas older infants did not, despite listening to the same stimuli. The lack of an effect with older infants replicates and extends recent findings by Hayashi, Tamekawa, and Kiritani (2001), suggesting that the variations in fundamental frequency and affect are not sufficient cues to IDS for older infants.     

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.     

Mothers' Speech to Hearing‐Impaired Infants and Children With Cochlear Implants

This study investigated the effects of age, hearing loss, and cochlear implantation on mothers' speech to infants and children. We recorded normal‐hearing (NH) mothers speaking to their children as they typically would do at home and speaking to an adult experimenter. Nine infants (10–37 months) were hearing‐impaired and had used a cochlear implant (CI) for 3 to 18 months. Eighteen NH infants and children were matched either by chronological age (10–37 months) or hearing experience (3–18 months) to the CI children. Prosodic characteristics such as fundamental frequency, utterance duration, and pause duration were measured across utterances in the speech samples. The results revealed that mothers use a typical infant‐directed speech style when speaking to hearing‐impaired children with CIs. The results also suggested that NH mothers speak with more similar vocal styles to NH children and hearing‐impaired children with CIs when matched by hearing experience rather than chronological age. Thus, mothers are sensitive to hearing experience and linguistic abilities of their NH children as well as hearing‐impaired children with CIs.     

The Relation between Mothers' Mirroring of Infants' Behavior and Maternal Mind‐Mindedness

Maternal mind‐mindedness, which is a measure of maternal mentalization involving mothers' speech, was examined as a predictor of mothers' mirroring of infant behavior during interaction. Five‐month‐old infants and their mothers engaged in a Still‐Face Task in which the mother's mirroring of the infant's behavior was assessed. After the task, the mother was shown a video of her infant in the task and asked to comment on what was happening for her infant; her comments were assessed for mind‐mindedness. Maternal mind‐mindedness when mothers were asked to reflect upon what was happening for their infants during the task predicted mothers' mirroring behaviors while engaged with their infants in the task. Maternal mirroring behavior may be a manifestation of maternal mentalization that is salient to infants.     

Fine‐Grained Analysis of Motionese: Eye Gaze,Object Exchanges,and Action Units in Infant‐Versus Adult‐Directed Action

Mothers modify their actions when demonstrating objects to infants versus adults. Such modifications have been called infant‐directed action (IDA) or motionese (Brand, Baldwin, & Ashburn, 2002). We investigated the IDA features of interactiveness and simplification by quantifying eye gaze, object exchanges, and action units enacted between exchanges in 42 mothers' demonstrations of novel objects to infants (6–8 months or 11–13 months) or adults. We found more eye gaze, more object exchanges, and fewer action types per turn in demonstrations to infants relative to adults. Unlike prior research using global measurements, we detected differences in behavior directed at infants of different ages: Shorter, more frequent gazes and more exchanges characterized demonstrations to older versus younger infants. These findings indicate the fruitfulness of fine‐grained analysis of IDA, and further clarify how adults may support infants' processing of human motion.     

Depressed and Well Mothers' Emotion Interpretation Accuracy and the Quality of Mother—Infant Interaction

The inadequate parenting associated with mothers' depression may be related to mothers' problems in interpreting infants' emotional expressions. The relations between depressed and well mothers' accuracy at interpreting babies' facial expressions and the quality of the mothers' interactions with their infants were examined. In partial support of our hypotheses, depressed mothers' level of depressive symptoms was associated with less accuracy, especially regarding positive emotions. Contrary to expectations, depressed mothers did not differ from well mothers in terms of their emotion accuracy. Furthermore, depressed mothers' accuracy at interpreting infants' emotions was not significantly related to the quality of their interaction with their infants; in contrast, well mothers' accuracy for infants' negative emotions was associated with better interaction quality. These findings provide new information about depressed mothers' emotional interpretations and their parenting. The different pattern of findings for depressed and well mothers suggests that other mediating factors are important, which are discussed.     

Maternal Depressive Symptoms and 6‐Month‐Old Infants' Sensitivity to Facial Expressions

We examined 6‐month‐old infants' abilities to discriminate smiling and frowning from neutral stimuli. In addition, we assessed the relationship between infants' preferences for varying intensities of smiling and frowning facial expressions and their mothers' history of depressive symptoms. Forty‐six infants were presented pairs of facial expressions, and their preferential looking time was recorded. They also participated in a 3‐min interaction with their mothers for which duration of both mother and infant gazing and smiling were coded. Analyses revealed that the infants reliably discriminated between varying intensities of smiling and frowning facial expressions and a paired neutral expression. In addition, infants' preferences for smiling and frowning expressions were related to self‐reports of maternal depressive symptoms experienced since the birth of the infant. Potential implications for social cognitive development are discussed.     

The Role of Mothers' Communication in Promoting Motivation for Math and Science Course‐Taking in High School

In the context of concerns about American youths' failure to take advanced math and science (MS) courses in high school, we examined mothers' communication with their adolescent about taking MS courses. At ninth grade, U.S. mothers (n = 130) were interviewed about their responses to hypothetical questions from their adolescent about the usefulness of algebra, geometry, calculus, biology, chemistry, and physics. Responses were coded for elaboration and making personal connections to the adolescent. The number of science, technology, engineering, and mathematics courses taken in 12th grade was obtained from school records. Mothers' use of personal connections predicted adolescents' MS interest and utility value, as well as actual MS course‐taking. Parents can play an important role in motivating their adolescent to take MS courses.     

Reunion Patterns in the Still‐Face Paradigm as Predicted by Maternal Sensitivity and Dyadic Coordination

Previous studies have suggested that the reunion episode of the still‐face procedure has the potential to reveal the regulatory resources of the mother–infant dyad that appear to be predictive of future adaptation. Nevertheless, differences across dyads with respect to these resources have received little attention, as also have the factors that are responsible for such differences. This study addresses this gap in the literature by testing whether the dyad reunion patterns can be predicted by the mothers' sensitivity assessed 3 months earlier, and by the contingent degree of the matched states in the play episode. Three dyadic patterns were identified through cluster analysis, which were characterized by playful, neutrally matched, and disrupted interactions. Multinomial logistic regression shows that the mothers' sensitivity predicts membership to the playful group, and the matched states in the play episode predict membership to the neutrally matched and disrupted groups. These findings show that the vulnerability to disrupt an ongoing interaction after a temporary perturbation is seen for only some dyads; moreover, they support the view of early regulatory development as a multidetermined achievement. Overall, these findings have important theoretical implications related to the identification of early regulatory difficulties as precursors of later developmental outcomes.     

Coregulation and the Quality of the Relationship in Full‐Term and Very Low‐Birthweight Preterm Infant‐Mother Dyads During Face‐To‐Face Interactions

Interactions with parents build the foundation for infants' social–emotional development. This study investigated coregulation of the interaction and quality of relationship between mothers and their 6‐month‐old full‐term (n = 43) and very low‐birthweight/preterm (VLBW/preterm; n = 44; ages corrected for prematurity) infants. The objectives were to examine (1) how coregulation changed following a perturbed interaction, (2) how coregulation differed between full‐term and VLBW/preterm infant–mother dyads, and (3) the association between coregulation and relationship quality. Coregulation was coded using the Revised Relational Coding System (Fogel et al., 2003). Quality of the relationship was measured using the Emotional Availability scales (Biringen et al., 2014; Carter et al., 1998). Dyads participated in the Still‐Face (SF) procedure (Tronick et al., 1978) consisting of two natural and one SF period where mothers assumed a neutral expression, refraining from interacting with their infants. Following the SF period, dyads engaged in more symmetrical and more disruptive patterns of coregulation. While full‐term dyads engaged in more sequential‐symmetrical, VLBW/preterm dyads engaged in more resonant‐symmetrical coregulation. These results suggest that VLBW/preterm dyads may show more emotional reactivity in their interactions than full‐term dyads; however, in both groups infant responsiveness and parenting stress influenced the types of coregulation exhibited.