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.     

Exploring in Silence: Hearing and Deaf Infants Explore Objects Differently Before Cochlear Implantation

Infant development has rarely been informed by the behavior of infants with sensory differences despite increasing recognition that infant behavior itself creates sensory learning opportunities. The purpose of this study of object exploration was to compare the behavior of hearing and deaf infants, with and without cochlear implants, in order to identify the effects of profound sensorineural hearing loss on infant exploration before cochlear implantation, the behavioral effects of access to auditory feedback after cochlear implantation, and the sensory motivation for exploration behaviors performed by hearing infants as well. The results showed that 9‐month‐old deaf infants explored objects as often as hearing infants but they used systematically different approaches and less variation before compared to after cochlear implantation. Potential associations between these early experiences and later learning are discussed in the context of embodied developmental theory, comparative studies, and research with adults. The data call for increased recognition of the active sensorimotor nature of infant learning and future research that investigates differences in sensorimotor experience as potential mechanisms in later learning and sequential memory development.     

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.     

Development of Pre-Word-Learning Skills in Infants with Cochlear Implants

Families of infants who are congenitally deaf now have the option of cochlear implantation at a very young age. In order to assess the effectiveness of early cochlear implantation, however, new behavioral procedures are needed to measure speech perception and language skills during infancy. One important component of language development is word learning-a complex skill that involves learning arbitrary relations between words and their referents. A precursor to word learning is the ability to perceive and encode intersensory relations between co-occurring auditory and visual events. Recent studies in infants with normal hearing have shown that intersensory redundancies, such as temporal synchrony, can facilitate the ability to learn arbitrary pairings between speech sounds and objects (Gogate & Bahrick, 1998). To investigate the early stages of learning arbitrary pairings of sounds and objects after cochlear implantation, we used the Preferential Looking Paradigm (PLP) to assess infants' ability to associate speech sounds to objects that moved in temporal synchrony with the onset and offsets of the signals. Children with normal hearing ranging in age from 6, 9, 18, and 30 months served as controls and demonstrated the ability to learn arbitrary pairings between temporally synchronous speech sounds and dynamic visual events. Infants who received their cochlear implants (CIs) at earlier ages (7-15 months of age) performed similarly to the infants with normal hearing after about 2-6 months of CI experience. In contrast, infants who received their implants at later ages (16-25 months of age) did not demonstrate learning of the associations within the context of this experiment. Possible implications of these findings are discussed.     

Infant vocalizations elicit simplified speech in childcare

Infant babbling has an important social function in promoting early language development by attracting caregiver attention and prompting parents' contingent, simplified speech, which is more learnable for infants. Here, we demonstrate that prelinguistic infant vocalizations also create learning opportunities for infants in childcare settings by eliciting simplified and more learnable linguistic information during teacher-infant interactions. We compared the rates and complexity of contingent and non-contingent verbal interactions of 34 childcare teachers during a one-on-one free play interaction with a familiar infant under their care (M = 12.6 months old). As compared to non-contingent utterances, teachers' contingent utterances included fewer unique words, a higher proportion of single-word responses, and a shorter mean length of utterances. Teachers did not change their response length based on infants' syllable type and were equally likely to respond to vowels and consonant-vowel vocalizations. Sources of individual differences in the simplification effect related to infant behaviors and teacher characteristics are discussed. The results parallel previous findings demonstrating the simplification effect in parent-infant interactions. That teachers also show this simplification effect when responding to infant vocalizations suggests the power of infant prelinguistic vocalizations for organizing caregiver attention in various settings to elicit simplified, learnable language.     

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.     

Young Infants Match Facial and Vocal Emotional Expressions of Other Infants

Research has demonstrated that infants recognize emotional expressions of adults in the first half year of life. We extended this research to a new domain, infant perception of the expressions of other infants. In an intermodal matching procedure, 3.5‐ and 5‐month‐old infants heard a series of infant vocal expressions (positive and negative affect) along with side‐by‐side dynamic videos in which one infant conveyed positive facial affect and another infant conveyed negative facial affect. Results demonstrated that 5‐month‐olds matched the vocal expressions with the affectively congruent facial expressions, whereas 3.5‐month‐olds showed no evidence of matching. These findings indicate that by 5 months of age, infants detect, discriminate, and match the facial and vocal affective displays of other infants. Further, because the facial and vocal expressions were portrayed by different infants and shared no face–voice synchrony, temporal, or intensity patterning, matching was likely based on detection of a more general affective valence common to the face and voice.     

Perpetual Silence,Not Silence for Moments: Hearing Loss of Children as Perceived by Hearing Bedouin Mothers

The Negev Bedouin population in southern Israel, a minority undergoing great social change, has a higher incidence of hearing loss than that reported elsewhere but has hardly been studied. Caring for a child with hearing loss often engenders parental stress because of the many tasks involved. Difficulty in accessing information and services, the lack of public transportation nearby, and other aspects of the living conditions of Negev Bedouin parents present additional challenges. These difficulties are further compounded by the unique socio-demographic and cultural characteristics of this indigenous population. This article presents the parenting experience of 20 hearing Bedouin mothers of children with hearing loss, explored in a qualitative phenomenological study. The findings indicate that the mothers’ perceptions of the child’s hearing loss affect how they cope with the birth and rearing of the child, their view of the child, and their attitude toward medical interventions. These findings, which portray an experience that is unique in many ways, contribute to the understanding of how an underserved, indigenous, and traditional population responds to congenital hearing loss. The findings also reveal the importance of the terminology with which parents describe their child’s hearing loss and the unique meanings it may have. Such knowledge is of particular importance for culturally sensitive and effective provision of social services and therapeutic interventions.     

Parental Linguistic Input and Its Relation to Toddlers’ Visual Attention in Joint Object Play: A Comparison Between Children with Normal Hearing and Children With Hearing Loss

Parent–child interactions are multimodal, often involving coordinated exchanges of visual and auditory information between the two partners. The current work focuses on the effect of children's hearing loss on parent–child interactions when parents and their toddlers jointly played with a set of toy objects. We compared the linguistic input received by toddlers with hearing loss (HL) and their chronological age‐matched (CA) and hearing age‐matched (HA) normal‐hearing peers. Moreover, we used head‐mounted eye trackers to examine how different parental linguistic input affected children's visual attention on objects when parents either led or followed children's attention during joint object play. Overall, parents of children with HL provided comparable amount of linguistic input as parents of the two normal‐hearing groups. However, the types of linguistic input produced by parents of children with HL were similar to the CA group in some ways and similar to the HA group in other ways. Interestingly, the effects of different types of linguistic input on extending the attention of children with HL qualitatively resembled the patterns seen in the CA group, even though the effects were less pronounced in the HL group. We discuss the implications of these results for our understanding of the reciprocal, dynamic, and multi‐factored nature of parent–child interactions.     

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.     

Looking Behavior and Smiling in Down Syndrome Infants

We studied the relation between direction of gaze and smiling in 15 typically developing infants and 15 infants with Down syndrome. All of them were videotaped during face-to-face interaction with their mothers at home, and while having access to their familiar toys. Results showed that mothers in the two groups behaved in a similar way; that Down syndrome infants looked at their mother's face for longer than typically developing children; and that the relationship between looking and smiling was similar in the two cases and reflected as an increase in the time the infant looked at its mother's face and a decrease in the time the infant looked at toys. It was deduced that Down syndrome infants are capable of distinguishing the differential significance of faces and toys, so that, in the same way as typically developing infants, they direct their affective behavior fundamentally towards the social element, which leads us to consider the affiliative function implied by this expression.     

Word Level Stress and Lexical Processing in 17‐Month‐Old Infants

Detailed representations enable infants to distinguish words from one another and more easily recognize new words. We examined whether 17‐month‐old infants encode word stress in their familiar word representations. In Experiment 1, infants were presented with pairs of familiar objects while hearing a target label either properly pronounced with the correct stress (e.g., baby /’be?bi/) or mis‐pronounced with the incorrect stress pattern (e.g., baby /be?’bi/). Infants mapped both the correctly stressed and mis‐stressed labels to the target objects; however, they were slower to fixate the target when hearing the mis‐stressed label. In Experiment 2, we examined whether infants appreciate that stress has a nonproductive role in English (i.e., altering the stress of a word does not typically signal a change in word meaning) by presenting infants with a familiar object paired with a novel object while hearing either correctly stressed or mis‐stressed familiar words (Experiment 2). Here, infants mapped the correctly stressed label to the familiar object but did not map the mis‐stressed label reliably to either the target or distractor objects. These findings suggest that word stress impacts the processing of familiar words, and infants have burgeoning knowledge that altering the stress pattern of a familiar word does not reliably signal a new referent.     

“Did I just do that?”—Six-month-olds learn the contingency between their vocalizations and a visual reward in 5 minutes

It has been shown that infants can increase or modify a motorically available behavior such as sucking, kicking, arm waving, etc., in response to a positive visual reinforcement (e.g., DeCasper & Fifer, 1980; Millar, 1990; Rochat & Striano, 1999; Rovee-Collier, 1997; Watson & Ramey, 1972). We tested infants to determine if they would also change their vocal behavior in response to contingent feedback, which lacks the social, emotional, and auditory modeling typical of parent-child interaction. Here, we show that in a single five-minute session infants increase the rate of their vocalizations in order to control the appearance of colorful shapes on an iPad screen. This is the first experimental study to demonstrate that infants can rapidly learn to increase their vocalizations, when given positive reinforcement with no social element. This work sets the foundations for future studies into the causal relationship between the number of early vocalizations and the onset of words. In addition, there are potential clinical applications for reinforcing vocal practice in infant populations who are at risk for poor language skills.     

Families by Adoption and Birth: II. Mother-Infant Cognitive Interactions

Adopted children are more likely to develop learning and school adjustment problems than are their nonadopted peers, despite that learning potential appears to be comparable in the two groups. In an effort to explain this phenomenon, the present study examined cognitive behavior repertoires in mothers and their healthy 5-month-old first infants during their normal daily routine in families by adoption and by birth. Two areas of functioning, vocal/verbal communication and exploration, were examined. Infants and mothers in both groups were similar in the frequency and ranking of a full array of age-appropriate cognitive behaviors. Both groups of babies experienced rich and comparable opportunities for the development of language competence. In the exploratory realm, group differences emerged for some infant measures; infants by birth were in an alert state and mouthed objects more than infants by adoption. Examination of the linkages among infant behaviors and between mothers and infants suggested that while mothers by birth and adoption provided comparable opportunities for exploration, infants by birth were engaging in exploratory behavior to a somewhat greater extent.     

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.     

Maternal Tactile Stimulation and the Neurodevelopment of Low Birth Weight Infants

The purpose of this study was to determine the relationship of early maternal touch to the neurodevelopmental status of low birth weight (LBW) infants. One hundred and eight LBW infants and their mothers were videotaped during a typical feeding when the infant was 3 months old. This tape was used to analyze both the mother's touch and other facets of caregiving behavior using standardized coding systems. Data on perinatal medical risk were also acquired through chart review, and neurodevelopmental tests were administered to the infants at age 1 year. Results indicate that infants whose mothers used more stimulating touch during caregiving had better visual‐motor skills at 1 year of age. In addition, infants of mothers who touched them frequently had more advanced gross motor development. Findings suggest that stimulating and frequent touch may help to compensate for early neurosensory deficits and promote neurodevelopment for LBW infants. Infant birth weight made the strongest contribution to all measures of infant neurodevelopmental status at age 1 year.     

Word Learning in Children Following Cochlear Implantation

An experimental procedure was developed to investigate word-learning skills of children who use cochlear implants (CIs). Using interactive play scenarios, 2- to 5-year olds were presented with sets of objects (Beanie Baby stuffed animals) and words for their names that corresponded to salient perceptual attributes (e.g., "horns" for a goat). Their knowledge of the word-object associations was measured immediately after exposure and then following a 2-hour delay. Children who use cochlear implants performed more poorly than age-matched children with typical hearing both receptively and expressively. Both groups of children showed retention of the word-object associations in the delayed testing conditions for words that were previously known. Our findings suggest that although pediatric CI users may have impaired phonological processing skills, their long-term memory for familiar words may be similar to children with typical hearing. Further, the methods that developed in this study should be useful for investigating other aspects of word learning in children who use CIs.     

The Impact on U.S. Society of Noise-Induced and Music-Induced Hearing Loss Caused by Personal Media Players

This article examines the effects noise-induced hearing loss (NIHL) and music-induced hearing loss (MIHL) may have on U.S. culture, with special attention given to such hearing loss that is associated with Personal Media Players (PMPs). With the advent of PMPs such as the iPod, hearing loss at a young age threatens to grow to alarmingly high proportions. The scale of total hearing loss in the United States is large enough to surprise most people; exceeding 10% of the population. The hearing loss landscape in U.S. culture today is very different from that of our grandparents'. Many new technologies such as PMPs have flooded our acoustical environment beyond any level previously imagined. What this article argues is that there is growing concern over, and statistical evidence of, both NIHL and MIHL due in some part to PMPs. The analysis further reveals ever-stronger correlations between the impact that hearing loss has on U.S. society regarding communication.     

Temporal Responsiveness in Mother–Child Dialogue: A Longitudinal Analysis of Children with Normal Hearing and Hearing Loss

Dialogue between conversational partners, including mothers and their children, is precisely timed. The predictability of this timing is important for establishing and maintaining interaction, communication, and learning. This longitudinal study examines changes in the response latency of utterances in dialogue between mothers and their normal hearing and hearing‐impaired children between 4 and 60 months of age. Mothers and their children showed parallel developmental trends, responding to each other more quickly at older ages. Beyond these age‐related group effects, significant dyadic effects were found in which individual children's latencies were related to those of their mothers, and vice versa. Developmental patterns did not significantly differ across hearing status groups, which may reflect the role of early identification and intervention in promoting positive developmental outcomes.     

Cultural Differences: Deaf and Hearing Researchers Working together

This article is based on several years of research done by the two authors, one of whom is Deaf and the other hearing. The paper discusses research done within the Deaf community using sign language. This is an estimated 50,000 people-the same number as those whose first language is Welsh. The Deaf community sees itself as a linguistic and cultural minority and as such is quite distinct from people with an acquired hearing loss, or those who are hard of hearing and who usually rely on written and spoken English through lipreading or writing things down. The paper sets this research in the context of cross-cultural research and looks at its connections with emancipatory research. The central discussion is in the form of a dialogue between the Deaf and hearing researchers and their personal responses to cultural differences. In the past Deaf people have been denied the opportunity of making their opinions known because research has used written or spoken language. Our research, using videocameras to record sign language and Deaf research using sign language to interview, provides a means of interviewing more suited to Deaf people than to hearing researchers. However, as the hearing culture is likely to be perceived as the dominant culture, there are bound to be differences when a hearing and Deaf researcher are working together within the Deaf community. These are the issues which we discuss within Deaf research.