How do deaf infants attain first signs?

In this study the development and alternation of nonreferential gestures were examined longitudinally in terms of the acquisition of Japanese sign language. Parent–child free‐play sessions in their home were videotaped at every monthly visit. Hand activities produced by two deaf infants of deaf parents are described and analyzed. Nonreferential gestures were observed frequently just before the occurrences of the first signs. They consisted of many rhythmic and repetitious movements. Nonreferential gestures became more complex and the number of them also increased as infants grew up. The comparison of nonreferential gestures and first signs revealed the continuity between them in terms of movements. In conclusion, nonreferential gestures are equivalent to a manual analog of vocal babbling.     

Variability in the initiation of articulatory movements in the speech of stutterers and normal speakers

This study was designed to investigate the differences between stutterers and normal speakers in phonatory and articulatory timing during the initiation of fluent utterances of monosyllabic words. Electromyographic recordings of four articulatory muscles and recordings of glottal vibrations were made of repetitive utterances of a series of monosyllabic words by 15 stutterers and 17 nonstutterers. These data were analyzed in terms of average interval times between voice onset and onset of EMG activity and between onset of EMG activity in each articulator and in terms of the intrasubject variability of these durational measures. Results showed that there were no significant differences between stutterers and nonstutterers in average interval times and that stutterers, in general, were significantly more variable in their speech onset timing. Findings are discussed in terms of recent hypotheses concerning the role of timing disturbances as the main source of speech disruption in stutterers.     

Baby babbling at five months linked to sex hormone levels in early infancy

Gender-dependent differentiation of the brain at morphological, neurochemical and functional levels of organization have been shown to be primarily controlled by sex differences in gonadal hormone concentrations during pre- and early postnatal development. Indeed, previous studies have reported that pre- and perinatal hormonal environments influence brain development and, consequently, affect sex specific long-term language outcomes.Herein, we investigated whether postnatal surges of estrogen (estradiol) and androgen (testosterone) may predict properties of pre-speech babbling at five months. This study is the first attempt to investigate a possible correlation between sex hormones and infants’ articulatory skills during the typical postnatal period of extended hormonal activity known as ‘mini-puberty.’ A hierarchical, multiple regression approach revealed a significant, robust positive relationship between 4-week concentrations of estradiol and individual articulatory skills. In contrast, testosterone concentrations at five months negatively correlated with articulatory skills at the same age in both boys and girls. Our findings reinforce the assumption of the importance of sex hormones for auditory–vocal development towards language in human infants.     

The role of production abilities in the perception of consonant category in infants

The influence of motor knowledge on speech perception is well established, but the functional role of the motor system is still poorly understood. The present study explores the hypothesis that speech production abilities may help infants discover phonetic categories in the speech stream, in spite of coarticulation effects. To this aim, we examined the influence of babbling abilities on consonant categorization in 6‐ and 9‐month‐old infants. Using an intersensory matching procedure, we investigated the infants’ capacity to associate auditory information about a consonant in various vowel contexts with visual information about the same consonant, and to map auditory and visual information onto a common phoneme representation. Moreover, a parental questionnaire evaluated the infants’ consonantal repertoire. In a first experiment using /b/–/d/ consonants, we found that infants who displayed babbling abilities and produced the /b/ and/or the /d/ consonants in repetitive sequences were able to correctly perform intersensory matching, while non‐babblers were not. In a second experiment using the /v/–/z/ pair, which is as visually contrasted as the /b/–/d/ pair but which is usually not produced at the tested ages, no significant matching was observed, for any group of infants, babbling or not. These results demonstrate, for the first time, that the emergence of babbling could play a role in the extraction of vowel‐independent representations for consonant place of articulation. They have important implications for speech perception theories, as they highlight the role of sensorimotor interactions in the development of phoneme representations during the first year of life.     

Multistable syllables as enacted percepts: a source of an asymmetric bias in the verbal transformation effect

Perceptual changes are experienced during rapid and continuous repetition of a speech form, leading to an auditory illusion known as the verbal transformation effect. Although verbal transformations are considered to reflect mainly the perceptual organization and interpretation of speech, the present study was designed to test whether or not speech production constraints may participate in the emergence of verbal representations. With this goal in mind, we examined whether variations in the articulatory cohesion of repeated nonsense words--specifically, temporal relationships between articulatory events--could lead to perceptual asymmetries in verbal transformations. The first experiment displayed variations in timing relations between two consonantal gestures embedded in various nonsense syllables in a repetitive speech production task. In the second experiment, French participants repeatedly uttered these syllables while searching for verbal transformation. Syllable transformation frequencies followed the temporal clustering between consonantal gestures: The more synchronized the gestures, the more stable and attractive the syllable. In the third experiment, which involved a covert repetition mode, the pattern was maintained without external speech movements. However, when a purely perceptual condition was used in a fourth experiment, the previously observed perceptual asymmetries of verbal transformations disappeared. These experiments demonstrate the existence of an asymmetric bias in the verbal transformation effect linked to articulatory control constraints. The persistence of this effect from an overt to a covert repetition procedure provides evidence that articulatory stability constraints originating from the action system may be involved in auditory imagery. The absence of the asymmetric bias during a purely auditory procedure rules out perceptual mechanisms as a possible explanation of the observed asymmetries.     

Why early linguistic milestones are delayed in children with Williams syndrome: late onset of hand banging as a possible rate–limiting constraint on the emergence of canonical babbling

In the present study, eight children with Williams syndrome were observed every 2 weeks between 6 months and 30 months of age when interacting with their mothers. When the collected data were transcribed in terms of both linguistic and motor activities, overall delay was found in terms of the onset of canonical babbling, first words, as well as various motor milestones in every child. The degree to which acquisition of each of the milestones was delayed was individually variable. Nevertheless, the onset of hand banging was found to be an indicator that predicted the onset of canonical babbling consistently among the children. Once canonical babbling was produced, moreover, the onset of first words was recorded during a following 2 to 3 month period. These findings appear to indicate the possibility that development of the motor ability to perform such rhythmic motor activity as hand banging acted as a control parameter for production of canonical syllables in the children.     

When infants talk,infants listen: pre‐babbling infants prefer listening to speech with infant vocal properties

To learn to produce speech, infants must effectively monitor and assess their own speech output. Yet very little is known about how infants perceive speech produced by an infant, which has higher voice pitch and formant frequencies compared to adult or child speech. Here, we tested whether pre‐babbling infants (at 4–6 months) prefer listening to vowel sounds with infant vocal properties over vowel sounds with adult vocal properties. A listening preference favoring infant vowels may derive from their higher voice pitch, which has been shown to attract infant attention in infant‐directed speech (IDS). In addition, infants' nascent articulatory abilities may induce a bias favoring infant speech given that 4‐ to 6‐month‐olds are beginning to produce vowel sounds. We created infant and adult /i/ (‘ee’) vowels using a production‐based synthesizer that simulates the act of speaking in talkers at different ages and then tested infants across four experiments using a sequential preferential listening task. The findings provide the first evidence that infants preferentially attend to vowel sounds with infant voice pitch and/or formants over vowel sounds with no infant‐like vocal properties, supporting the view that infants' production abilities influence how they process infant speech. The findings with respect to voice pitch also reveal parallels between IDS and infant speech, raising new questions about the role of this speech register in infant development. Research exploring the underpinnings and impact of this perceptual bias can expand our understanding of infant language development.     

Emergent Control of Manual and Vocal-Motor Activity in Relation to the Development of Speech

Babbling typically precedes, resembles, and conceivably facilitates development of speech, and yet there is no accepted neurobiological characterization of babbling. Here we report a study of infants′ developing control of vocal behavior in relation to manual activity performed under differing conditions of audibility. We hypothesized that babbling is associated with the onset of left-lateralized motor control, as expressed in repetitive right-handed activity, and that audibility facilitates such activity, Sixty-one normally developing infants were seen before (N = 21) or at various intervals following (N = 40) the onset of babbling. In experimental trials, audible or inaudible rattles were placed in left or right hands equally often. Analysis of manual activity revealed little shaking movement in the youngest and vocally least differentiated infants, and a sharp increase in shaking in slightly older infants who had recently begun to babble. Surprisingly, audibility only marginally enhanced shaking activity. A dextral bias was evident in the shaking of infants who had recently begun to babble, but not in younger or older infants. These and other findings suggest that the left cerebral hemisphere may be disproportionately involved in the production of repetitive vocal-motor activity as occurs in babbling.     

Social feedback to infants' babbling facilitates rapid phonological learning

Infants' prelinguistic vocalizations are rarely considered relevant for communicative development. As a result, there are few studies of mechanisms underlying developmental changes in prelinguistic vocal production. Here we report the first evidence that caregivers' speech to babbling infants provides crucial, real-time guidance to the development of prelinguistic vocalizations. Mothers of 9.5-month-old infants were instructed to provide models of vocal production timed to be either contingent or noncontingent on their infants' babbling. Infants given contingent feedback rapidly restructured their babbling, incorporating phonological patterns from caregivers' speech, but infants given noncontingent feedback did not. The new vocalizations of the infants in the contingent condition shared phonological form but not phonetic content with their mothers' speech. Thus, prelinguistic infants learned new vocal forms by discovering phonological patterns in their mothers' contingent speech and then generalizing from these patterns.     

Intuitive identification of infant vocal sounds by parents

Parents are remarkably accurate observers of their infants’‘canonical babbling’, the production of well‐formed syllables. With very little training, many parents across a wide range of socioeconomic status make flawless judgments of canonical stage onset. The results of concordance studies between parental and trained‐observer judgments support the idea that recognition of canonical babbling may be intuitive. Without instruction, parents identify the onset of canonical babbling when it occurs, and thereafter they begin to interpret sounds produced by children in ways that may encourage word learning. The fact that parents can provide accurate information about stage of vocal development, along with the fact that late onset of canonical babbling has been shown to be an extremely important indicator of risk for hearing loss and language‐related disabilities, suggests the possibility of using a brief interview to identify infants at risk.     

Consistency of maternal cognitions and principles across the first five months following preterm and term deliveries

The aims of this study were to examine and compare the development of parenting cognitions and principles in mothers following preterm and term deliveries. Parenting cognitions about child development, including thinking that is restricted to single causes and single outcomes (categorical thinking) and thinking that takes into account multiple perspectives (perspectivist thinking), have been shown to relate to child outcomes. Parenting principles about using routines (structure) or infant cues (attunement) to guide daily caregiving have been shown to relate to caregiving practices. We investigated the continuity and stability of parenting cognitions and principles in the days following birth to 5 months postpartum for mothers of infants born term and preterm. All parenting cognitions were stable across time. Categorical thinking increased at a group level across time in mothers of preterm, but not term, infants. Perspectivist thinking increased at a group level for first-time mothers (regardless of birth status) and tended to be lower in mothers of preterm infants. Structure at birth did not predict later structure (and so was unstable) in mothers of preterm, but not term, infants and neither group changed in mean level across time. Attunement was consistent across time in both groups of mothers. These results indicate that prematurity has multiple, diverse effects on parenting beliefs, which may in turn influence maternal behavior and child outcomes.     

The influence of babbling patterns on the processing of speech

This study compared the preference of 27 British English- and 26 Welsh-learning infants for nonwords featuring consonants that occur with equal frequency in the input but that are produced either with equal frequency (Welsh) or with differing frequency (British English) in infant vocalizations. For the English infants a significant difference in looking times was related to the extent of production of the nonword consonants. The Welsh infants, who showed no production preference for either consonant, exhibited no such influence of production patterns on their response to the nonwords. The results are consistent with a previous study that suggested that pre-linguistic babbling helps shape the processing of input speech, serving as an articulatory filter that selectively makes production patterns more salient in the input.     

Principles,laws, theories and the metaphysics of science

In this paper an outline of a metaphysical conception of modern science is presented in which a fundamental distinction is drawn between scientific principles, laws and theories. On this view, ontologicalprinciples, rather than e.g. empirical data, constitute the core of science. The most fundamental of these principles are three in number, being, more particularly (A) the principle of the uniformity of nature, (B) the principle of the perpetuity of substance, and (C) the principle of causality.These three principles set basic constraints on the methodology of both empirical and theoretical science. The uniformity principle is central to the empirical aspect of science, suggesting a methodology consisting in the attempt to discover empiricallaws, while the causality principle is central to the theoretical aspect of science, suggesting the postulation of scientifictheories capable of indicating the causal basis of the laws. And the perpetuity principle functions so as to form a bridge between the theories and the laws.By distinguishing between principles, laws and theories in this way, a dimension is added to the analysis of modern science which allows for a more realistic account of its nature.     

The correlation of P-center adjustments with articulatory and acoustic events

To evaluate articulatory models of perceptual center (P-center) location, listeners performed perceptual adjustments on stimuli which were extracted from a corpus of articulatory data. To avoid streaming effects, the stimuli were not edited to obtain temporal variation; instead, they varied in stress and segmental content. Adjustments were evaluated as to their simultaneity with acoustic and articulatory events. The first experiment yielded various articulatory and acoustic correlates of P-center location; the second yielded different articulatory predictors and no acoustic effective predictors. Multiple correlation analyses showed a variation from P-center locations predicted by the articulatory events that were associated with other predictors. Thus, P-center locations do not correspond to any particular kinematic articulatory event, but rather to a complex of events taken from throughout the stimuli. These results are discussed in terms of their relevance to a model of P-centers as indices of underlying gestural timing.     

Short-term memory as a response preparation state

This review considers recent findings on motor-response programming which indicate that there is a temporary mode of storage for response commands. This storage, which is distinct from long-term memory, is required for emission of a programmed response even when there are no explicit requirements for memory. Although this system is considered to be primarily a stage in response control rather than a memory system, it may mediate verbal short-term memory when encoded in articulatory form. The implications of this perspective on short-term memory are considered.     

Electrophysiological evidence of phonetic normalization across coarticulation in infants

The auditory neural representations of infants can easily be studied with electroencephalography using mismatch experimental designs. We recorded high‐density event‐related potentials while 3‐month‐old infants were listening to trials consisting of CV syllables produced with different vowels (/bX/ or /gX/). The consonant remained the same for the first three syllables, followed (or not) by a change in the fourth position. A consonant change evoked a significant difference around the second auditory peak (400–600 ms) relative to control trials. This mismatch response demonstrates that the infants robustly categorized the consonant despite coarticulation that blurs the phonetic cues, and at an age at which they do not produce these consonants themselves. This response was obtained even when infants had no visual articulatory information to help them to track the consonant repetition. In combination with previous studies establishing categorical perception and normalization across speakers, this result demonstrates that preverbal infants already have abstract phonetic representation integrating over acoustical features in the first months of life.     

Nonverbal psychotherapy with infants

A psychoanalytically oriented nonverbal technique was developed to help four withdrawn infants. In three of the four cases, treatment began in the first year of life. Each case presents a different combination of infant/caregiver difficulties that contributed to the infant's withdrawal. After analysis of the difficulties in the infant's first relationship, appropriate preverbal sensory experiences served as a means to establish communication between mother and infant. Regression to the newborn stage gave mother and child a chance to reexperience the earliest stages of infancy. This process led to the recovery of the failing primary bond between mother and child and enabled the infants to compensate for constitutional deficits that prevented adequate attachment. Very early recognition and treatment of some mother-infant attachment disorders may prevent emotional withdrawal, functional retardation, and failure to form meaningful relationships.     

A model for the treatment of eating disorders of adolescents in a specialized centre in The Netherlands

Treatment of adolescent patients with eating disorders has to take into account that these patients differ in age, their stage of development, and the constellation and functioning of their family life. Our treatment model takes these factors into account and is family and cognitive behaviourally orientated. The work has developed and changed in recent years, based on our experiences over the past ten years, as well as in combination with ideas we picked up from the experiences of colleagues elsewhere, be they via oral reports or written papers. Our approach is flexible; yet it also offers a structured containment for the patient, both by the treatment team and the parents. We aim, as much as possible, to let the family members carry out the treatment, providing them with the environment and the tools they need. Including the family members actively in the treatment of their ill daughter and teaching the parents how to help their child at home is the core of our philosophy, and we believe that this prevents prolonged inpatient stays or readmissions. This paper describes the different ways and settings in which we try to carry out our work.     

Co‐occurences of preverbal vocal behavior and motor action in early infancy

This study reports on co‐occurrence of vocal behaviors and motor actions in infants in the prelinguistic stage. Four Japanese infants were studied longitudinally from the age of 6 months to 11 months. For all the infants, a 40 min sample was coded for each monthly period. The vocalizations produced by the infants co‐occurred with their rhythmic actions with high frequency, particularly in the period preceding the onset of canonical babbling. Acoustical analysis was conducted on the vocalizations recorded before and after the period when co‐occurrence took place most frequently. Among the vocalizations recorded in the period when co‐occurrence appeared most frequently, those that co‐occurred with rhythmic action had significantly shorter syllable duration and shorter formant‐frequency transition duration compared with those that did not co‐occur with rhythmic action. The rapid transitions and short syllables were similar to patterns of duration found in mature speech. The acoustic features remained even after co‐occurrence disappeared. These findings suggest that co‐occurrence of rhythmic action and vocal behavior may contribute to the infant’s acquisition of the ability to perform the rapid glottal and articulatory movements that are indispensable for spoken language acquisition.