Coincidence or cascade? The temporal relation between locomotor behaviors and the emergence of stranger anxiety

Two infant milestones, self-propelled locomotion and stranger anxiety, tend to emerge at a similar age in development. An adaptive relation may exist in which the onset of one influences the development of the other in individual children. We examine whether these milestones systematically co-occur and whether one reliably precedes the other. In the current study, 104 parents completed weekly online surveys between 6 and 12 months, noting milestones as they occurred. Onset ages for locomotor behaviors were correlated with onset of stranger anxiety over and above a milestone in a third domain, namely consonant-vowel babbling. These data suggest that infants’ earliest locomotor behaviors may play a role in galvanizing the development of stranger anxiety.     

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.     

Babbling development as seen in canonical babbling ratios: A naturalistic evaluation of all-day recordings

Canonical babbling (CB) is critical in forming foundations for speech. Research has shown that the emergence of CB precedes first words, predicts language outcomes, and is delayed in infants with several communicative disorders. We seek a naturalistic portrayal of CB development, using all-day home recordings to evaluate the influences of age, language, and social circumstances on infant CB production. Thus we address the nature of very early language foundations and how they can be modulated. This is the first study to evaluate possible interactions of language and social circumstance in the development of babbling. We examined the effects of age (6 and 11 months), language/culture (English and Chinese), and social circumstances (during infant-directed speech [IDS], during infant overhearing of adult-directed speech [ADS], or when infants were alone) on canonical babbling ratios (CBR = canonical syllables/total syllables). The results showed a three-way interaction of infant age by infant language/culture by social circumstance. The complexity of the results forces us to recognize that a variety of factors can interact in the development of foundations for language, and that both the infant vocal response to the language/culture environment and the language/culture environment of the infant may change across age.     

Sex differences in language first appear in gesture

Children differ in how quickly they reach linguistic milestones. Boys typically produce their first multi‐word sentences later than girls do. We ask here whether there are sex differences in children’s gestures that precede, and presage, these sex differences in speech. To explore this question, we observed 22 girls and 18 boys every 4 months as they progressed from one‐word speech to multi‐word speech. We found that boys not only produced speech + speech (S+S) combinations (‘drink juice’) 3 months later than girls, but they also produced gesture + speech (G+S) combinations expressing the same types of semantic relations (‘eat’ + point at cookie) 3 months later than girls. Because G+S combinations are produced earlier than S+S combinations, children’s gestures provide the first sign that boys are likely to lag behind girls in the onset of sentence constructions.     

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.     

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.     

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.     

Follow-up of children identified with and treated for a motor delay of nonspecifiable etiology

Forty-eight 7- to 8-year-old children who had been diagnosed prior to 48 months of age as being developmentally motor delayed and had received therapy for their delay were followed up and assessed for motor, intellectual, and psychological development as well as for self-perceived competence and school achievement. These children were found to be significantly inferior on all of these variables, except for self-competence, when compared with matched nondelayed controls. Those delayed children who had begun treatment prior to 24 months of age demonstrated significantly greater gains in motor function at follow-up, had significantly higher IQs, performed better at school, and participated in more peer-related activities than did the delayed children who began treatment after 24 months. This study supports the hypotheses that (1) young children diagnosed as being developmentally motor delayed demonstrate subsequent intellectual and psychological problems when in the primary grades and (2) that the age at onset of intervention therapy for the delay is significantly related to outcome (benefit of therapy).     

How are social-emotional and behavioral competences and problems at age 1 year associated with infant motor development? A general population study

Based on limitations in previous research evidence, we concluded that more research is needed for deeper understanding of how social-emotional and behavioral (SEB) outcomes among infant-toddler-aged children in the general population are associated with early motor development. In this study, we investigated associations between early competencies and problems, as measured by the Brief Infant-Toddler Social and Emotional Assessment (BITSEA), and the timing of achievement of the main gross and fine motor milestones usually attained during the first year of life in a general population context. The study sample consisted of 515 infants (mean age 12.9 [SD 0.9] months) and their parents (514 mothers, 434 fathers), who were recruited in child health centers in Northern Finland. The infants were divided into two groups, based on their BITSEA screen status, and motor milestone achievement ages were compared across BITSEA screen status No Concern and Of-Concern infants. An Of-Concern screen status on the maternal and paternal Competence scale and Autism spectrum disorder (ASD) item cluster was associated with later infant achievement ages for gross motor milestones. By contrast, infants who were screened to be in the Of-Concern range on the maternal Problem scale achieved gross motor milestones earlier than infants with the corresponding No Concern screen status. No significant associations were found between the paternal Problem scale screen status and infant motor development. In further analyses, the strongest associations were found between an Of-Concern screen status on the paternal Competence scale and ASD item cluster and infant motor development. The findings indicate that the inclusion of infant motor developmental information may assist early identification and the clinical interpretation of parental reports of early SEB problems. Clinical implications of the current findings are discussed in the paper.     

Young children use their hands to tell their mothers what to say

Children produce their first gestures before their first words, and their first gesture+word sentences before their first word+word sentences. These gestural accomplishments have been found not only to predate linguistic milestones, but also to predict them. Findings of this sort suggest that gesture itself might be playing a role in the language‐learning process. But what role does it play? Children's gestures could elicit from their mothers the kinds of words and sentences that the children need to hear in order to take their next linguistic step. We examined maternal responses to the gestures and speech that 10 children produced during the one‐word period. We found that all 10 mothers ‘translated’ their children's gestures into words, providing timely models for how one‐ and two‐word ideas can be expressed in English. Gesture thus offers a mechanism by which children can point out their thoughts to mothers, who then calibrate their speech to those thoughts, and potentially facilitate language‐learning.     

A time series analysis of the relation between motor skill acquisition and sleep in infancy

To systematically examine the relation between motor milestone onset and disruption of night sleep in infancy, three families kept microgenetic, prospective, daily checklist diaries of their infants’ motor behavior and sleep (197-313 observation days; 19,000 diary entries). Process control and interrupted time series analyses examined whether deviations from the moving average for night wakings and evening sleep duration were temporally linked to motor skill onset and tested for meaningful differences in individual sleep patterns before and after skill onset. Model assumptions defined skill onset as first day of occurrence or as mastery and moving average windows as 3, 7, or 14 days. Changes in infants’ sleep patterns were associated with changing expertise for motor milestones. The temporal relation varied depending on infant and sleep parameter. Intensive longitudinal data collection may increase our understanding of micro-events in infant development.     

词汇飞跃: 早期语言发展的里程碑──来自五名汉语儿童的跟踪报告

本文通过对五名汉语儿童的长期跟踪调查,旨在从词汇增长、句法出现和语义发展三方面发掘词汇飞跃时期儿童的语言特征。结果显示：儿童在18个月左右词汇迅猛增长,出现词汇飞跃现象;标志句法出现的词语组合和词汇飞跃在时间上紧密相连;词汇飞跃期儿童语义发展显著,体现为过度延伸词的逐渐减少及下位层次词的逐渐增加。词汇飞跃是汉语儿童早期语言发展的里程碑,表明其在词汇、句法和语义多个语言层面的飞跃。     

Functional analysis and treatment of self-injurious behavior in young children a summary of 30 cases

The assessment and treatment of self-injurious behavior (SIB) has received much attention in the literature; however, few studies have focused on early intervention for this behavior. In the current study, functional analyses with developmentally appropriate modifications were conducted in an outpatient clinic with 30 children (aged 10 months to 4 years 11 months) to assess SIB and problem behavior in its early stages. The reported mean age of SIB onset was 17 months, and head banging was the most prevalent topography. Functional analyses identified sources of reinforcement for SIB in 62.1% of cases; with the inclusion of all forms of problem behavior, sources of reinforcement were identified for 87.5% of cases. Function-based treatments were developed for 24 cases, with functional communication training prescribed most often (70.8% of cases). Implications of these findings for the development of early intervention programs for SIB are discussed.     

Operating principles in repetitive babbling: A cognitive continuity approach

A case study of the period of repetitive babbling in one child (Dutch) is reported. A cognitive continuity theory is presented, which views repetitive babbling as a systematic, continuous and largely self-directed process of exploration, during which the child uses certain operating principles in the construction of his own ‘springboard’ to speech.Two operating principles identified are: a combination principle, consisting of the combining of articulatory acts which previously have been exercised separately, and a variation principle, consisting of the trying out of the same type of articulatory act in different articulatory contexts.Four stages are distinguished in the development of repetitive babbling. In the first stage no combinations occur, in the second stage combination mainly takes the form of repetition and in the third stage it takes the form of concatenating different babbling types as well. In the fourth stage the concatenations grow more varied and less repetitive in character. The subsequent stages of jargon babbling and first words are discussed shortly and their continuity with repetitive babbling is pointed out.     

Imitation of body postures and hand movements in children with specific language impairment

Within the domain-general theory of language impairment, this study examined body posture and hand movement imitation in children with specific language impairment (SLI) and in their age-matched peers. Participants included 40 children with SLI (5 years 3 months to 6 years 10 months of age) and 40 children with typical language development (5 years 3 months to 6 years 7 months of age). Five tests were used to examine imitation and its underlying cognitive and motor skills such as kinesthesia, working memory, and gross motor coordination. It was hypothesized that children with SLI show a weakness in imitation of body postures and that this deficit is not equally influenced by the underlying cognitive and motor skills. There was a group effect in each cognitive and motor task, but only gross motor coordination proved to be a strong predictor of imitation in children with SLI. In contrast, hand movement imitation was strongly predicted by performance in the Kinesthesia task in typically developing children. Thus, the findings show not only that children with SLI performed more poorly on the imitation tasks than their typically developing peers but also that the groups’ performances showed qualitative differences. The results of the current study provide additional support to the view that the weaknesses in children with SLI are not limited to the verbal domain.     

The relation between children's conceptual functioning with color and color term acquisition

Young children experience considerable difficulty in learning their first few color terms. One explanation for this difficulty is that initially they lack a conceptual representation of color sufficiently abstract to support word meaning. This hypothesis, that prior to learning color terms children do not represent color as an abstraction, was tested in two experiments using samples of 25- to 39-month-olds and 20- to 32-month-olds. Children's ability to conceptually represent color and their knowledge of color terms were assessed, and a strong association was found between the ability to make inferences based on color and the comprehension of color words. Children who did not comprehend color terms were unsuccessful at a conceptual task that required them to represent color as a property independent of the particular objects that displayed it. The results suggest that the initial absence of an abstract representation of color contributes to the difficulty that young children encounter when first learning color words.     

Kids observing other kids' hands: visuomotor priming in children

We investigated motor resonance in children using a priming paradigm. Participants were asked to judge the weight of an object shortly primed by a hand in an action-related posture (grasp) or a non action-related one (fist). The hand prime could belong to a child or to an adult. We found faster response times when the object was preceded by a grasp hand posture (motor resonance effect). More crucially, participants were faster when the prime was a child's hand, suggesting that it could belong to their body schema, particularly when the child's hand was followed by a light object (motor simulation effect). A control experiment helped us to clarify the role of the hand prime. To our knowledge this is the first behavioral evidence of motor simulation and motor resonance in children. Implications of the results for the development of the sense of body ownership and for conceptual development are discussed.     

Gestural development and its relation to a child's early vocabulary

Gesture and language are tightly connected during the development of a child's communication skills. Gestures mostly precede and define the way of language development; even opposite direction has been found. Few recent studies have focused on the relationship between specific gestures and specific word categories, emphasising that the onset of one gesture type predicts the onset of certain word categories or of the earliest word combinations.The aim of this study was to analyse predicative roles of different gesture types on the onset of first word categories in a child's early expressive vocabulary. Our data show that different types of gestures predict different types of word production. Object gestures predict open-class words from the age of 13 months, and gestural routines predict closed-class words and social terms from 8 months. Receptive vocabulary has a strong mediating role for all linguistically defined categories (open- and closed-class words) but not for social terms, which are the largest word category in a child's early expressive vocabulary. Accordingly, main contribution of this study is to define the impact of different gesture types on early expressive vocabulary and to determine the role of receptive vocabulary in gesture-expressive vocabulary relation in the Croatian language.     

Can hearing puter activate pupil? Phonological competition and the processing of reduced spoken words in spontaneous conversations

In listeners' daily communicative exchanges, they most often hear casual speech, in which words are often produced with fewer segments, rather than the careful speech used in most psycholinguistic experiments. Three experiments examined phonological competition during the recognition of reduced forms such as [pjut?r] for computer using a target-absent variant of the visual world paradigm. Listeners' eye movements were tracked upon hearing canonical and reduced forms as they looked at displays of four printed words. One of the words was phonologically similar to the canonical pronunciation of the target word, one word was similar to the reduced pronunciation, and two words served as unrelated distractors. When spoken targets were presented in isolation (Experiment 1) and in sentential contexts (Experiment 2), competition was modulated as a function of the target word form. When reduced targets were presented in sentential contexts, listeners were probabilistically more likely to first fixate reduced-form competitors before shifting their eye gaze to canonical-form competitors. Experiment 3, in which the original /p/ from [pjut?r] was replaced with a “real” onset /p/, showed an effect of cross-splicing in the late time window. We conjecture that these results fit best with the notion that speech reductions initially activate competitors that are similar to the phonological surface form of the reduction, but that listeners nevertheless can exploit fine phonetic detail to reconstruct strongly reduced forms to their canonical counterparts.     

An ERP investigation of location invariance in masked repetition priming

In an experiment combining masked repetition priming and the recording of event-related potentials (ERPs) the location of prime stimuli relative to centrally located target words was manipulated. Prime words could appear at the same location as targets or shifted one letter position to the right or to the left. Repetition priming effects (amplitude differences across the repeat vs. unrelated prime conditions) were found in a series of ERP components starting at around 100 msec posttarget onset. The earliest of these, the N/P150 component, was found to be sensitive to prime location. Repetition priming was only apparent with centrally located primes in this component. Repetition priming effects in later components (N250 and N400), on the other hand, were not affected by prime location. The results are interpreted in terms of location-specific letter detectors that map onto a higher level, location-invariant orthographic code for printed words.