Can a Click be a Word?: Infants' Learning of Non‐Native Words

Forms that are nonlinguistic markers in one language (i.e., “tsk‐tsk” in English) may be part of the phoneme inventory—and hence part of words—in another language. In the current paper, we demonstrate that infants' ability to learn words containing unfamiliar language sounds is influenced by the age and vocabulary size of the infant learner, as well as by cues to the speaker's referential intent. When referential cues were available, infants at 14 months learned words with non‐native speech sounds, but at 20 months only those infants with smaller vocabularies succeeded. When no referential cues were present, infants at both 14 and 20 months failed to learn the same words. The implications of the relation between linguistic sophistication and non‐native word learning are discussed.     

Families,Not Parents,Differ: Development of Communication in Finnish Infants

This longitudinal study on Finnish families was conducted to identify developmental differences in family‐level communication among mothers, fathers, and their infants during the second half of the infant's first year, and associations with infants' later language and communicative skills. We examined coregulated communication of parent‐infant dyads during 5‐min laboratory play sessions at 7 and 11 months. Few differences in mutually regulated communicative exchanges emerged between maternal and paternal dyads, and few developmental changes were found across the whole sample. Families with different communication profiles were identified, and changes rather than stability characterized communicative development at the family level. The family‐level differences at 7 months predicted variation in children's language and communicative skills at 14 months.     

Avoidance of Heights on the Visual Cliff in Newly Walking Infants

Work with infants on the “visual cliff” links avoidance of drop‐offs to experience with self‐produced locomotion. Adolph's (2002) research on infants' perception of slope and gap traversability suggests that learning to avoid falling down is highly specific to the postural context in which it occurs. Infants, for example, who have learned to avoid crossing risky slopes while crawling must learn anew such avoidance when they start walking. Do newly walking infants avoid crossing the drop‐off of the visual cliff? Twenty prewalking but experienced crawling infants were compared with 20 similarly aged newly walking infants on their reactions to the visual cliff. Newly walking infants avoided moving onto the cliff's deep side even more consistently than did the prewalking crawlers. Thus, in the context of drop‐offs in visual texture, our results show that once avoidance of drop‐offs is established under conditions of crawling, it is developmentally maintained once infants begin walking.     

Mothers’ Work Status and 17‐Month‐Olds’ Productive Vocabulary

Literature examining the effects of mothers’ work status on infant language development is mixed, with little focus on varying work schedules and early vocabulary. We use naturalistic data to analyze the productive vocabulary of 44 17‐month‐olds in relation to mothers’ work status (full time, part time, stay at home) at 6 and 18 months. Infants who experienced a combination of care from mothers and other caretakers had larger productive vocabularies than infants in solely full‐time maternal or solely other‐caretaker care. Our results draw from naturalistic data to suggest that this care combination may be particularly beneficial for early lexical development.     

The Ability to Map Differentially Stressed Labels to Objects Predicts Language Development at 24 months in 12‐month‐olds at High Risk for Autism

Sensitivity to language‐specific stress patterns during infancy facilitates finding, mapping, and recognizing words, and early preferences for the predominate stress pattern of the infant's native language have been argued to facilitate language relevant outcomes (Ference & Curtin, 2013 Journal of Experimental Child Psychology, 116, 891; Weber et al., 2005 Cognitive Brain Research, 25, 180). We examined 12‐month‐old infant siblings of typically developing children (SIBS‐TD) and infant siblings of children diagnosed with autism spectrum disorder (ASD; SIBS‐A) on their ability to map differentially stressed labels to objects. We also examined whether success at this task relates to infants’ vocabulary size at 12 months, and more specifically to SIBS‐A's vocabulary at both 12 and 24 months. SIBS‐TD successfully mapped the word–object pairings, which related to their vocabulary comprehension at 12 months. In contrast, SIBS‐A as a group did not map the word–object pairings, which was unrelated to vocabulary size at 12 months. However, success on this task for SIBS‐A predicted expressive language abilities at 24 months using the Mullen Scales of Early Learning (MSEL; Mullen, 1995 Mullen Scales of Early Learning. Circle Pines, MN: American Guidance) and the MacArthur‐Bates Communicative Development Inventory (MB‐CDI; Fenson et al., 1993 MacArthur Communicative Development Inventory: Users Guide and Technical Manual. San Diego, CA: Singular Publishing Company). Our study is the first to demonstrate that 12‐month‐old SIBS‐A who succeed at word mapping using lexical stress are more likely to have stronger expressive language abilities at 24 months.     

Relationship Between Maternal Sensitivity During Early Interaction and Maternal Ability in Perceiving Infants' Body and Face

Maternal sensitivity has been considered an indicator of mother‐infant quality interaction, however little is known about the perception processes associated to this parental behavior style. Here we aimed to explore the relationship between maternal sensitivity during a face‐to‐face interaction with their infants and maternal ability in perceiving infants' body and face. Thirty‐six 6 month‐old infants and their mothers were videotaped during a mother‐infant interaction to identify those with high and low sensitivity. Then, mothers were tested using an inversion effect paradigm requiring the visual discrimination of upright and inverted pictures of whole bodies and faces of their own and unfamiliar infants; this allowed estimation of their configural perceptual processing abilities. Results showed that high‐sensitivity mothers showed reduced body configural processing for others' infants as compared to configural processing of their own infant, whereas low‐sensitivity mothers were engaged in comparable body configural processing independently from infant identity. Infants' face configural processing did not distinguish between high‐ and low‐sensitivity mothers. Our findings suggest that high‐sensitivity mothers have refined their use of configural processing of body postures to be selective for their own infants, suggesting that this visuo‐perceptual strategy makes much more efficient the mothers' ability in detecting, discriminating and recognizing own infant's cues.     

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.     

Chinese and English Infants' Tone Perception: Evidence for Perceptual Reorganization

Over half the world's population speaks a tone language, yet infant speech perception research has typically focused on consonants and vowels. Very young infants can discriminate a wide range of native and nonnative consonants and vowels, and then in a process of perceptual reorganization over the 1st year, discrimination of most nonnative speech sounds deteriorates. We investigated perceptual reorganization for tones by testing 6‐ and 9‐month‐old infants from tone (Chinese) and nontone (English) language environments for speech (lexical tone) and nonspeech (violin sound) tone discrimination in both cross‐sectional and longitudinal studies. Overall, Chinese infants performed equally well at 6 and 9 months for both speech and nonspeech tone discrimination. Conversely, English infants' discrimination of lexical tone declined between 6 and 9 months of age, whereas their nonspeech tone discrimination remained constant. These results indicate that the reorganization of tone perception is a function of the native language environment, and that this reorganization is linguistically based. Supplementary materials to this article are available on the World Wide Web at http:www.infancyarchives.com     

Maternal Sensitivity and the Learning‐Promoting Effects of Depressed and Nondepressed Mothers' Infant‐Directed Speech

The hypothesis that aspects of current mother‐infant interactions predict an infant's response to maternal infant‐directed speech (IDS) was tested. Relative to infants of nondepressed mothers, those of depressed mothers acquired weaker voice‐face associations in response to their own mothers' IDS in a conditioned‐attention paradigm, although this was partially attributable to demographic differences between the 2 groups. The extent of fundamental frequency modulation (ΔF₀) in maternal IDS was smaller for infants of depressed than nondepressed mothers, but did not predict infant learning. However, Emotional Availability Scale ratings of maternal sensitivity, coded from videotapes of mothers and infants engaged in a brief play interaction, were significant predictors of infant learning, even after maternal depression, its demographic correlates, and antidepressant medication use had been taken into account. These findings are consistent with a role for experience‐dependent processes in determining the effects of IDS on infant learning.     

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.     

Becoming a Communicative Partner: Infant Contingent Responsiveness to Maternal Language and Gestures

Infant contingent responsiveness to maternal language and gestures was examined in 190 Mexican American, Dominican American, and African American infant–mother dyads when infants were 14 and 24 months. Dyads were video‐recorded during book‐sharing and play. Videos were coded for the timing of infants’ vocalizations and gestures and mothers’ referential language (i.e., statements that inform infants about objects and events in the world; e.g., “That's a big doggy!”), regulatory language (i.e., statements that regulate infants’ attention or actions; e.g., “Look at that”, “Put it down!”), and gestures. Infants of all three ethnicities responded within 3 sec of mothers’ language and gestures, increased their responsiveness over development, and displayed specificity in their responses: They vocalized and gestured following mothers’ referential language and gestures, but were less likely than chance to communicate following mothers’ regulatory language. At an individual level, responsive infants had responsive mothers.     

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‐directed speech to infants at risk for dyslexia: A novel cross‐dyad design

When mothers speak to infants at risk for developmental dyslexia, they do not hyperarticulate vowels in their infant‐directed speech (IDS). Here, we used an innovative cross‐dyad design to investigate whether the absence of vowel hyperarticulation in IDS to at‐risk infants is a product of maternal infant‐directed behavior or of infants’ parent‐directed cues. Interactions between mothers and infants who were at risk or not at risk for dyslexia were recorded in three conditions: when mothers interacted with (a) their own infants, (b) infants who were not their own but of the same risk status, and (c) infants who were not their own and of the opposite risk status. This design revealed both infant and parent effects. Mothers of not‐at‐risk infants hyperarticulated vowels significantly more when speaking to not‐at‐risk than to at‐risk infants. In contrast, mothers of at‐risk infants hyperarticulated vowels significantly less than NAR mothers, and this was irrespective of infant status. Mothers of not‐at‐risk infants thus adjusted their IDS to the infant's risk status, while mothers of at‐risk infants did not. We suggest that IDS is determined reciprocally by characteristics of both partners in the dyad: Both infant and maternal factors are essential for the vowel hyperarticulation component of IDS.     

Mothers' Verbal and Nonverbal Strategies in Relation to Infants' Object‐Directed Actions in Real Time and Across the First Three Years in Ethnically Diverse Families

We examined maternal behavioral strategies in relation to infants' object‐directed actions in real time and over developmental time in 206 mother–infant dyads from African American, Dominican immigrant, and Mexican immigrant backgrounds. Mothers were asked to share a set of beads and strings with their infants when children were 14, 24, and 36 months. We coded three types of maternal strategies—eliciting attention, instructive assistance, and encouragement—which could be expressed verbally (e.g., “look”, “turn it”, “good job!”) or physically (i.e., through gestures, hands‐on guidance, or transfer of objects). We also coded infants' unassisted bead‐stringing. Across ethnic groups and ages, mothers' hands‐on guidance and object transfer increased the likelihood that infants would follow with unassisted bead‐stringing during real‐time interaction. Over developmental time, mothers modified their strategies: They displayed fewer attention‐getting strategies and more encouragement across infant ages, and peaked in their provision of instructive assistance when infants were 24 months. Additionally, Mexican mothers displayed more nonverbal strategies (e.g., gestures, hands‐on guidance) than did African American and/or Dominican mothers, who displayed more verbal strategies (e.g., attention‐getting and encouraging language). Developmental and real‐time patterns in mother–infant object‐related interactions generalize across ethnicities, although mothers' emphases on specific strategies are culture specific.     

Fathers' Early Emotion Talk: Associations With Income,Ethnicity, and Family Factors

Contextual, mother‐, child‐, and father‐level variables were examined in association with fathers' emotion talk to infants during a shared picture book activity, in an ethnically diverse, low‐income sample (N = 549). Significant main effects included the rate of emotion talk from fathers' romantic partners (i.e., the infant's mother), infant attention and distress, and sensitive parenting. Significant interactions were also found. Higher income African American fathers referred to negative emotions more than non‐African American higher income fathers. In addition, African American fathers who demonstrated more negative and intrusive parenting referred to positive emotions more than non‐African American fathers who demonstrated negative and intrusive parenting. Our findings support family systems theory and, specifically, the interdependence of individuals' behaviors within the family unit. Interaction effects are discussed with respect to cultural variation in beliefs about parenting behaviors and the cultural experience of African Americans, including the Black cultural experience and the minority experience.     

The Value of Vocalizing: 10‐Month‐Olds' Vocal Usage Relates to Language Outcomes at 15 Months

The interaction between infant's communicative competence and responsiveness of caregivers facilitates the transition from prelinguistic to linguistic communication. It is thus important to know how infants' communicative behavior changes in relation to different caregiver responses; furthermore, how infants' modification of communicative behavior relates to language outcomes. We investigated 39 10‐month‐old infants' communication as a function of mothers' attention and responses and the relationship to language outcomes at 15 months. We elicited infants' communicative behavior in three conditions: (1) joint attention: Mothers were visually attending and responding to infants' attention and interest; (2) available: Mothers were visually attending to infants, but not responding contingently to infants' attention and interest; (3) unavailable: Mothers were not attending to infants nor responding to them. Infants vocalized more when mothers attended and responded to them (conditions 1 and 2) than when mothers did not (condition 3), but infants' gesture and gesture‐vocal production did not differ across conditions. Furthermore, infants' production of a higher proportion of vocalizations in the unavailable condition relative to the joint attention condition correlated with, and predicted, infants' language scores at 15 months. Thus, infants who appear to be aware of the social effects of vocalizations may learn words better.     

Demands on Finite Cognitive Capacity Cause Infants' Perseverative Errors

This research unites traditionally disparate developmental domains—cognition and locomotion—to examine the classic cognitive issue of the development of inhibition in infancy. In 2 locomotor A‐not‐B tasks, 13‐month‐old walking infants inhibited a prepotent response under low task demands (walking on flat ground), but perseverated under increased task demands (descending a staircase). Despite elimination of factors previously associated with infant perseveration, infants still perseverated in the difficult stairs condition. Increasing cognitive load by manipulating task difficulty affected infants' ability to inhibit repeated responses that were no longer appropriate. Evidence supports a cognitive capacity account of infant perseveration, in which infants' performance depends on allocation of cognitive and attentional resources.     

Individual Differences in the Contribution of Maternal Soothing to Infant Distress Reduction

This study investigates individual differences in the contribution of specific maternal regulatory behaviors to the mother‐infant dyad's regulation of infant distress response. Additionally, we examined the stability of infants' stress responses and the stability of specific maternal soothing behaviors. The sample included 128 mother‐infant dyads that were observed during an inoculation at 2 and 6 months. The average intensity of infant cry response showed modest stability across age only before controlling for the infant's general state of irritability, and the duration of crying was not stable. Of the 8 specific maternal regulatory behaviors studied, affection, touching, and vocalizing showed the strongest stability across infant age. Finally, an index of the contingency between maternal soothing and infant cry reduction at 2 months predicted shorter cry duration but not cry intensity at 6 months. The results of this study indicate that infants whose mothers showed a greater contribution to reducing their distress at 2 months showed a shorter duration of crying 4 months later. This suggests a possible longitudinal influence of maternal regulation on infants' distress responses.     

Maternal Disrupted Communication During Face‐to‐Face Interaction at 4 months: Relation to Maternal and Infant Cortisol Among at‐Risk Families

The study evaluated the association between maternal disrupted communication and the reactivity and regulation of the psychobiology of the stress response in infancy. Mothers and infants were recruited via the National Health Service from the 20% most economically impoverished data zones in a suburban region of Scotland. Mothers (N = 63; M age = 25.9) and their 4‐month‐old infants (35 boys, 28 girls) were videotaped interacting for 8 min, including a still‐face procedure as a stress inducer and a 5‐min coded recovery period. Saliva samples were collected from the dyads prior to, during, and after the still‐face procedure and later assayed for cortisol. Level of disruption in maternal communication with the infant was coded from the 5‐min videotaped interaction during the recovery period which followed the still‐face procedure. Severely disrupted maternal communication was associated with lower levels of maternal cortisol and a greater divergence between mothers' and infants' cortisol levels. Results point to low maternal cortisol as a possible mechanism contributing to the mother's difficulty in sensitively attuning to her infant's cues, which in turn has implications for the infant's reactivity to and recovery from a mild stressor in early infancy.