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This study suggests that familiarity and novelty preferences in infant experimental tasks can in some instances be interpreted together as a single indicator of language advance. We provide evidence to support this idea based on our use of the auditory headturn preference paradigm to record responses to words likely to be either familiar or unfamiliar to infants. Fifty-nine 10-month-old infants were tested. The task elicited mixed preferences: familiarity (longer average looks to the words likely to be familiar to the infants), novelty (longer average looks to the words likely to be unfamiliar) and no-preference (similar-length of looks to both type of words). The infants who exhibited either a familiarity or a novelty response were more advanced on independent indices of phonetic advance than the infants who showed no preference. In addition, infants exhibiting novelty responses were more lexically advanced than either the infants who exhibited familiarity or those who showed no-preference. The results provide partial support for Hunter and Ames' (1988) developmental model of attention in infancy and suggest caution when interpreting studies indexed to chronological age.

A child's first words mark the emergence of a uniquely human ability. Theories of the developmental steps that pave the way for word production have proposed that either vocal or gestural precursors are key. These accounts were tested by assessing the developmental synchrony in the onset of babbling, pointing, and word production for 46 infants observed monthly between the ages of 9 and 18 months. Babbling and pointing did not develop in tight synchrony and babble onset alone predicted first words. Pointing and maternal education emerged as predictors of lexical knowledge only in relation to a measure taken at 18 months. This suggests a far more important role for early phonological development in the creation of the lexicon than previously thought.

Studies of phonological development that combine speech-processing experiments with observation and analysis of production remain rare, although production experience is necessarily relevant to developmental advance. Here we focus on three proposals regarding the relationship of production to word learning: (1) "Articulatory filter": The hypothesis that children are influenced in noticing words in input speech by their resemblance to patterns they can produce has recently received experimental support. (2) "Systematization and regression": It is proposed that the decline in accuracy that follows first-word production is the consequence of an increase in systematicity (with renewed accuracy emerging only later). (3) "Word-production experience facilitates new word learning": Evidence that expressive vocabulary growth in itself facilitates new word learning supports the idea that knowledge is gradient, involving increases in stability and reliability with repeated exposure and use.

The early relationship between children's emerging articulatory abilities and their capacity to process speech input was investigated, following recent studies with English-learning infants. Twenty-six monolingual Italian-learning infants were tested at 6 months (no consistent and stable use of consonants, or vocal motor schemes [VMS]) and at the age at which they displayed use of at least one VMS. Perceptual testing was based on lists of nonwords containing one of three categories of sounds each: produced by infant (own VMS), not yet produced but typical of that age (other VMS), or not typically produced by infants at that age (non-VMS). In addition, size of expressive lexicon at 12 months and 18 months was assessed using an Italian version of the MacArthur-Bates Communicative Development Inventory (CDI). The results confirmed a relation between infant preverbal production and attentional response to VMS and also between age at first VMS and 12-month vocabulary. Maternal input is shown not to be a specific determinant of individual infant production preferences. A comparison between the English and Italian experimental findings shows a stronger attentional response to VMS in isolated words as compared to sentences. These results confirm the existence of an interaction between perception and production that helps to shape the way that language develops.

Previous studies have shown that by 11 but not by 10 months infants recognize words that have become familiar from everyday life independently of the experimental setting. This study explored the ability of 10-, 11-, and 12- month-old infants to recognize familiar words in sentential context, without experimental training. The headturn preference procedure was used to contrast passages containing words likely to be familiar to the infants with passages containing words unlikely to have been previously heard. Two stimulus words were inserted near the beginning and end of each of a set of simple sentence frames. The ability to recognize the familiar words within sentences emerged only at 12 months of age. The contrast between segmentation abilities as they emerge as a result of everyday exposure to language, as assessed here, and those abilities as measured in studies in which words are experimentally trained is discussed in terms of memory-based mechanisms.

Purpose: In this study, the authors looked for effects of vocal practice on phonological working memory. Method: A longitudinal design was used, combining both naturalistic observations and a nonword repetition test. Fifteen 26-month-olds (12 of whom were followed from age 11 months) were administered a nonword test including real words, "standard" nonwords (identical for all children), and nonwords based on individual children's production inventory (IN and OUT words). Results: A strong relationship was found between (a) length of experience with consonant production and (b) nonword repetition and between (a) differential experience with specific consonants through production and (b) performance on the IN versus OUT words. Conclusions: Performance depended on familiarity with words or their subunits and was strongest for real words, weaker for IN words, and weakest for OUT words. The results demonstrate the important role of speech production in the construction of phonological working memory.

The interaction between prosodic and segmental aspects of infant representations for speech was explored using the head-turn paradigm, with untrained everyday familiar words and phrases as stimuli. At 11 months English-learning infants, like French infants (Halle & Boysson-Bardies, 1994), attended significantly longer to a list of familiar lexical items than to a phonetically comparable rare list, but 9-month-olds did not. Reversing the stress pattern of the familiar items failed to block word-form recognition in 11-month-olds, although a time-course analysis showed that it delayed the infant response. Changing the initial consonant of English words did block word recognition while change to the second consonant did not. Time-course analyses of both the English and the original French data showed that altering the consonant of the unaccented syllable delays word-form recognition in both languages while change to the accented syllable has a stronger effect in English than in French.

This research determined frequency importance functions (FIFs) for words, sentences, and continuous discourse under comparable conditions so that contextual effects of speech could be isolated. A male talker recorded 616 monosyllabic words, 176 meaningful sentences, and 44 continuous discourse (CD) passages. Twenty-four participants with normal hearing made intelligibility estimates of the CD passages and sentences and identified words in each of 44 low- and high-pass filtering and signal-to-noise ratio conditions. Plots of frequency versus percent of contributed intelligibility, or the FIFs, revealed that the frequency band that contributes the most to intelligibility is centered near 2000 Hz for all three types of speech. The results show a single peak in the importance function and a statistical analysis of the shape of the FIF (with kurtosis the pertinent measure) shows that there is a significant difference in the shape of the FIF based upon speech type. The data were also calculated into near-octave bands with similar results. The statistical analysis presented provides the basis for a test of the hypothesis: The degree of context or message redundancy is related to the relative importance of the frequency bands. The findings potentially have clinical as well as predictive implications. KEY WORDS: speech, perception, words, sentences, discourse

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. [ABSTRACT FROM AUTHOR]

Focuses on studies conducted on speech perception and segmentation in the prelinguistic period, highlighting the role of trochaic accentual pattern in English and French. Details on the role of prosody in early language acquisition; What findings of research conducted on language acquisition indicated; Assumptions made regarding language acquisition.

This study suggests that familiarity and novelty preferences in infant experimental tasks can in some instances be interpreted together as a single indicator of language advance. We provide evidence to support this idea based on our use of the auditory headturn preference paradigm to record responses to words likely to be either familiar or unfamiliar to infants. Fifty-nine 10-month-old infants were tested. The task elicited mixed preferences: familiarity (longer average looks to the words likely to be familiar to the infants), novelty (longer average looks to the words likely to be unfamiliar) and no-preference (similar-length of looks to both type of words). The infants who exhibited either a familiarity or a novelty response were more advanced on independent indices of phonetic advance than the infants who showed no preference. In addition, infants exhibiting novelty responses were more lexically advanced than either the infants who exhibited familiarity or those who showed no-preference. The results provide partial support for Hunter and Ames' (1988) developmental model of attention in infancy and suggest caution when interpreting studies indexed to chronological age.