Adult-child discourse: Developmental interaction between information processing and linguistic knowledge

In the present study, the discourse interaction between adult and child was examined in terms of the content of their utterances, and the linguistic and contextual relations between their messages, in order to investigate how children use the information from adults' input sentences to form contingent responses. The analyses described were based on longitudinal data from four children from approximately 21 to 36 months of age. Categories of child discourse, their development and their interactions with aspects of prior adult utterances form the major results of the study. Child utterances were identified as adjacent (immediately preceded by an adult utterance), or as nonadjacent (not immediately preceded by an adult utterance). Adjacent utterances were either contingent (shared the same topic and added new information relative to the topic of the prior utterance), imitative (shared the same topic but did not add new information), or noncontingent (did not share the same topic). From the beginning, the adjacent speech was greater than nonadjacent speech. Contingent speech increased over time; in particular, linguistically contingent speech (speech that expanded the verb relation of the prior adult utterance with added or replaced constituents within a clause) showed the greatest developmental increase. Linguistically contingent speech occurred more often after questions than nonquestions. The results are discussed in terms of how the differential requirements for processing information in antecedent messages is related to language learning.     

Processes and products of imitation: Additional evidence that imitation is progressive

The spontaneous verbal interactions of two children and their babysitter were recorded over the period of half a year. The children were males, from middle-class backgrounds, and 2 years old at the beginning of the observation period. Imitated utterances were found to surpass quantitatively spontaneous ones on the dimensions of grammatical and semantic complexity. With few exceptions, new structures appeared first in imitative utterances and only later in spontaneous ones. Both the higher complexity and the prior appearance of new constructions in imitative utterances suggest that imitation fulfilled a progressive function for the observed children.     

Maltreated Children Use More Grammatical Negations

Many studies reveal a strong impact of childhood maltreatment on language development, mainly resulting in shorter utterances, less rich vocabulary, or a delay in grammatical complexity. However, different theories suggest the possibility for resilience—a positive adaptation to an otherwise adverse environment—in children who experienced childhood maltreatment. Here, we investigated different measures for language development in spontaneous speech, examining whether childhood maltreatment leads to a language deficit only or whether it can also result in differences in language use due to a possible adaptation to a toxic environment. We compared spontaneous speech during therapeutic peer-play sessions of 32 maltreated and 32 non-maltreated children from the same preschool and equivalent in gender, age (2 to 5 years), home neighborhood, ethnicity, and family income. Maltreatment status was reported by formal child protection reports, and corroborated by independent social service reports. We investigated general language sophistication (i.e., vocabulary, talkativeness, mean length of utterance), as well as grammatical development (i.e., use of plurals, tense, grammatical negations). We found that maltreated and non-maltreated children showed similar sophistication across all linguistic measures, except for the use of grammatical negations. Maltreated children used twice as many grammatical negations as non-maltreated children. The use of this highly complex grammatical structure shows an advanced linguistic skill, which shows that childhood maltreatment does not necessarily lead to a language deficit. The result might indicate the development of a negativity bias in the structure of spontaneous language due to an adaptation to their experiences.     

Psycholinguistics discovers the operant: a review of Roger Brown's A first language: the early stages

Brown's book is selectively reviewed with the aim of noting points of similarity between Brown's psycholinguistic analysis of language acquisition and a functional analysis of verbal behavior. Brown divides early language acquisition into five stages, based on mean length of utterance in samples of child speech. His book concentrates on Stage I, when mean length of utterance first rises above 1.0, indicating that children are beginning to speak in multi-morphemic utterances, and Stage II, when mean length of utterance in morphemes is about 2.25. Multi-morphemic utterances in Stage I consist mainly of ordered sequences of uninflected nouns and verbs, the order being that of the simple declarative sentence (agent-action-indirect object-direct object-locative). The review attempts a theoretical analysis of the functional stimulus control of Stage I syntactic order, concluding that the control must originate partly in relations among events in the environment and partly in covert autoclitic verbal behavior. Increases in mean length of utterance in Stage II are mainly due to the appearance of several “grammatical morphemes” such as the progressive -ing inflection on verbs and the plural -s inflection on nouns. The review attempts a behavioral paraphrase, again in terms of tacts and autoclitics, of Brown's psycholinguistic analysis of grammatical morphemes, concluding that Stage II displays the further development, building on Stage I, of the combined control of verbal behavior by relations in the environment and covert self-generated verbal stimuli. Similarities between Brown's psycholinguistic analysis and a functional analysis of language acquisition suggest that the two viewpoints are converging on a common concern with the stimulus control of verbal behavior.     

Influences of rate, length, and complexity on speech disfluency in a single-speech sample in preschool children who stutter

The purpose of the present study was (1) to determine whether speech rate, utterance length, and grammatical complexity (number of clauses and clausal constituents per utterance) influenced stuttering-like disfluencies as children became more disfluent at the end of a 1200-syllable speech sample [Sawyer, J., & Yairi, E. (2006). The effect of sample size on the assessment of stuttering severity. American Journal of Speech-Language Pathology, 15, 36-44] and (2) to explore the interaction of speech rate, length, and grammatical complexity at the beginning (syllables 1-300, Section A) and the end (syllables 901-1200, Section B) of the speech sample. Participants were eight boys and six girls (M=40.9 months) who were selected from the Sawyer and Yairi [Sawyer, J., & Yairi, E. (2006). The effect of sample size on the assessment of stuttering severity. American Journal of Speech-Language Pathology, 15, 36-44] study. Mean length of utterance (MLU) in morphemes, the number of clauses, clausal constituents, and articulation rate, measured in syllables per second were analyzed from the children's conversational speech. The median split procedure [Logan, K., & Conture, E. (1995). Length, grammatical complexity, and rate differences in stuttered and fluent conversational utterances of children who stutter. Journal of Fluency Disorders, 20, 35-61; Yaruss, J. S. (1997). Utterance timing and childhood stuttering. Journal of Fluency Disorders, 22, 263-286] was used to study interactions between articulation rate, utterance length, and grammatical complexity across the two sections. The mean number of clauses per utterance, clausal constituents per utterance, and articulation rate revealed no significant differences between Section A and Section B, whereas MLU significantly increased in Section B (p=.013). Clausal constituents and MLU were significantly correlated both in Sections A and B. The median split procedure revealed trends for utterances characterized as high length and low-speech rate to be greater in number in Section B than A, but the differences were not significant. EDUCATIONAL OBJECTIVES: The reader will learn about and be able to: (a) describe the influence of grammatical complexity and mean length of utterance on disfluent speech; (b) compare different procedures for assessing speech rate and determine why the effects of articulation rate have been inconclusive; (c) discuss procedures for comparing length, rate, and complexity across a single-speech sample; and (d) explain why therapeutic methods that emphasize shorter utterance lengths, rather than only slower speech rates, are advisable in establishing fluency in preschool children who stutter.     

Isolated words enhance statistical language learning in infancy

Infants are adept at tracking statistical regularities to identify word boundaries in pause-free speech. However, researchers have questioned the relevance of statistical learning mechanisms to language acquisition, since previous studies have used simplified artificial languages that ignore the variability of real language input. The experiments reported here embraced a key dimension of variability in infant-directed speech. English-learning infants (8-10 months) listened briefly to natural Italian speech that contained either fluent speech only or a combination of fluent speech and single-word utterances. Listening times revealed successful learning of the statistical properties of target words only when words appeared both in fluent speech and in isolation; brief exposure to fluent speech alone was not sufficient to facilitate detection of the words' statistical properties. This investigation suggests that statistical learning mechanisms actually benefit from variability in utterance length, and provides the first evidence that isolated words and longer utterances act in concert to support infant word segmentation.     

Integrating constraints for learning word-referent mappings

Learning word-referent mappings is complex because the word and its referent tend to co-occur with multiple other words and potential referents. Such complexity has led to proposals for a host of constraints on learning, though how these constraints may interact has not yet been investigated in detail. In this paper, we investigated interactions between word co-occurrence constraints and cross-situational statistics in word learning. Analyses of child-directed speech revealed that when both object-referring and non-referring words occurred in the utterance, referring words were more likely to be preceded by a determiner than when the utterance contained only referring words. In a word learning study containing both referring and non-referring words, learning was facilitated when non-referring words contributed grammatical constraints analogous to determiners. The complexity of multi-word utterances provides an opportunity for co-occurrence constraints to contribute to word-referent mapping, and the learning mechanism is able to integrate these multiple sources of information.     

Use of repetition to facilitate spontaneous language acquisition

The role of repetition as a facilitator of spontaneous language acquisition was examined in a 12-month longitudinal study of three children: John, Mindy, and Ashley. Imitation was first defined in a traditional fashion as the exact repetition of a model utterance, within five utterances, without changing the model except to reduce it. During the single-word utterance period, John entered words into his vocabulary by imitating them and then using them spontaneously, while the two girls did not. He also imitated longer utterances than he produced spontaneously while the two girls did not. At the same time, John showed the most rapid language acquisition of the three children. John did not use imitation, as defined, to enter new syntactic-semantic relations into his speech during the two-word stage. However, when the definition of imitation was broadened to include other kinds of repetitions such as repetitions with expansion, either of the child's own productions or of those of others, it was found that repetitions played a significant role in the acquisition of new vocabulary and new syntactic-semantic relations in two-word utterances.This article is based, in part, on a Ph.D. dissertation submitted to the Department of Psychology, University of Denver, in 1976. Portions of the article were presented at the Wisconsin Education Research Association, Oshkosh, Wisconsin, December 1–2, 1977. The research was undertaken while the author was an NIMH predoctoral fellow, 5F01 MH55918-02 MTHL, and was also supported by a Grant Foundation grant for graduate student research to Dr. Marshall Haith and a Spencer Foundation grant to Dr. Kurt Fischer.     

Alignment to visual speech information

Speech alignment is the tendency for interlocutors to unconsciously imitate one another’s speaking style. Alignment also occurs when a talker is asked to shadow recorded words (e.g., Shockley, Sabadini, & Fowler, 2004). In two experiments, we examined whether alignment could be induced with visual (lipread) speech and with auditory speech. In Experiment 1, we asked subjects to lipread and shadow out loud a model silently uttering words. The results indicate that shadowed utterances sounded more similar to the model’s utterances than did subjects’ nonshadowed read utterances. This suggests that speech alignment can be based on visual speech. In Experiment 2, we tested whether raters could perceive alignment across modalities. Raters were asked to judge the relative similarity between a model’s visual (silent video) utterance and subjects’ audio utterances. The subjects’ shadowed utterances were again judged as more similar to the model’s than were read utterances, suggesting that raters are sensitive to cross-modal similarity between aligned words.     

Childhood stuttering and speech disfluencies in relation to children's mean length of utterance: a preliminary study

The purpose of this study was to examine the influence of utterance length and complexity relative to the children's mean length of utterance (MLU) on stuttering-like disfluencies (SLDs) for children who stutter (CWS) and nonstuttering-like disfluencies (nonSLDs) for children who do not stutter (CWNS). Participants were 12 (3;1-5;11, years;months) children: 6 CWS and 6 age-matched (+/-5 months) CWNS, with equal numbers in each talker group (CWS and CWNS) exhibiting MLU from the lower to the upper end of normal limits. Data were based on audio-video recordings of each child in two separate settings (i.e., home and laboratory) during loosely structured, 30-min parent-child conversational interactions and analyzed in terms of each participant's utterance length, MLU, frequency and type of speech disfluency. Results indicate that utterances above children's MLU are more apt to be stuttered or disfluent and that both stuttering-like as well as nonstuttering-like disfluencies are most apt to occur on utterances that are both long and complex. Findings were taken to support the hypothesis that the relative "match" or "mismatch" between linguistic components of an utterance (i.e., utterance length and complexity) and a child's language proficiency (i.e., MLU) influences the frequency of the child's stuttering/speech disfluency. EDUCATIONAL OBJECTIVES: The reader will learn about and be able to: (1) compare different procedures for assessing the relationship among stuttering, length and complexity of utterance, (2) describe the difference between relative and absolute measures of utterance length, (3) discuss the measurement and value of mean length of utterance and its possible contributions to childhood stuttering, and (4) describe how length and complexity influence nonstuttering-like disfluencies of children who stutter as well as the stuttering-like disfluencies of children who do not stutter.     

The gestures of a gorilla: language acquisition in another pongid

A female lowland gorilla, Koko, has been engaged in an ongoing language program since July 1972 when she was 1 year old. During the first 30 months of training she acquired a vocabulary of 100 words in American Sign Language which she spontaneously combined into meaningful and often novel statements of up to 11 signs in length. The gorilla is using a rapidly expanding vocabulary of signs to express semantic and possibly grammatical relations similar to those expressed by human children in the early stages of language acquisition. Patterns of generalization, gradual increase in mean length of utterance, and innovative use of gestural language are discussed in relation to data available on children and chimpanzees.     

Comprehending illocutionary force

According to speech act theory (Searle, 1969), utterances have both a propositional content and an illocutionary force (the speech act performed with the utterance). Four experiments were conducted to examine whether utterance comprehension involves speech act recognition. Participants in all experiments first read remarks that could be characterized by a particular speech act (e.g., beg). A recognition probe reaction time procedure was used in Experiments 1 and 2; participants indicated whether a probe word had literally appeared in the last remark that they had read. Participants were significantly slower at making this judgment (and made significantly more errors) when the probe represented the speech act performed with the prior remark than when it did not. A lexical decision task was used in Experiments 3 and 4, and participants were significantly faster at verifying target words representing the speech act performed with a remark, relative to control words. Overall, the results suggest that speech act recognition may be an important component of the comprehension of conversational remarks.     

Effect of Rate,Intonation, and Sentence Length on Nigerian Children's Imitation of Adults' Utterances

This Nigerian study replicated the work of Bonvillian et al. (1979) on the effects of rate, intonation, and sentence length on children's sentence imitation. Nursery school children (N = 12; M age = 5 years, 0.5 months) were asked to imitate sentences that varied in rate of presentation, intonation, and length. Results revealed better imitation of shorter sentences than longer ones, of sentences read at a rate nearer the children's normal speech rate than those read at a faster or slower rate, and of sentences read with normal intonation than those read with flat intonation. These findings replicated those of Bonvillian et al., while indicating an even stronger effect of intonation in the Nigerian sample, because its effect was not limited to long sentences but affected all sentences. Adults' utterances to children are often slow, with exaggerated intonation. The present findings suggest that such modifications in adults' speech facilitate children's language comprehension.     

Is language acquired through imitation?

The role of imitation in language acquisition is examined, including data from the psycholinguistic, operant, and social learning areas. From the psycholinguistic data, four empirical statements have been extracted: (1) there is no evidence that spontaneous imitations of adult speech influence grammatical development, (2) imitation of speech does not appear to occur with frequency beyond age 3 years, (3) speech and hence imitation are not necessary for the comprehension of linguistic structures, and (4) most utterances of a child are novel and therefore could not have been exactly modeled. The first and second propositions are seen to be based on a too restrictive definition of imitation-immediate and exact copying. Selective imitation-a functional relationship involving similarity of a particular form or function of the model's responses-is proposed as an alternative, thus leaving the validity of statements (1) and (2) in question. Concerning assertion (4), certain data from the operant literature are presented as evidence of the compatibility of novel responding and modeling, imitation, and reinforcement. Finally, it is proposed that statement (3) suggests a mechanism by which selective imitation can be understood. A three-stage process is proposed in which comprehension of a grammatical form sets the stage for selective imitation of that structure, which leads in turn to spontaneous production. Thus imitation is a process by which new syntactic structures can be first introduced into the productive mode.     

Starting over: international adoption as a natural experiment in language development

Language development is characterized by predictable shifts in the words children produce and the complexity of their utterances. Because acquisition typically occurs simultaneously with maturation and cognitive development, it is difficult to determine the causes of these shifts. We explored how acquisition proceeds in the absence of possible cognitive or maturational roadblocks, by examining the acquisition of English in internationally adopted preschoolers. Like infants, and unlike other second-language learners, these children acquire language from child-directed speech, without access to bilingual informants. Parental reports and speech samples were collected from 27 preschoolers, 3 to 18 months after they were adopted from China. These children showed the same developmental patterns in language production as monolingual infants (matched for vocabulary size). Early on, their vocabularies were dominated by nouns, their utterances were short, and grammatical morphemes were generally omitted. Children at later stages had more diverse vocabularies and produced longer utterances with more grammatical morphemes.     

Phonological considerations in children's early imitative and spontaneous speech

The relationship between the phonological characteristics of young children's unsolicited imitative and spontaneous speech was examined as a function of (1) the level of the children's linguistics development, and (2) the children's knowledge of the words imitated. A greater number of phonological discrepancies were seen in children with lexicons of fewer than 40 words than in children with larger lexical repertories. Such discrepancies were also more likely when the children displayed little comprehension of the words they were imitating. This tendency was particularly strong in the children with limited lexicons. The results are discussed in terms of a developmental shift in the bases of children's phonological organization.     

Syntagmatically oriented reactions in the early phases of speech development]

Within a longitudinal observational study of two children aged from 18 to 36 months spontaneous reactive utterances were analysed. It could be found syntagmatic reactions without topic coherence with the utterances of the previous speaker. The specialty of these utterances consists in the fact that the child, after having perceived certain words in the parental utterances, creates an association to the previously heard grammatical context. The results are discussed within the scope of problems of language acquisition in children.     

Language evolution in children with cochlear implants

The capacity to incorporate significant words into the existing vocabulary and to use these words to form sentences with more mature syntactic structures emerges over a considerable time course in young deaf children who have undergone a cochlear implantation. The purpose of this follow-up study is to document the nature and time span of language production--in morphosyntactic and lexical skills--when a child's first experience with language sounds is provided artificially through electrical stimulation. To examine the development of these two aspects of linguistic processing, five deaf French children, all enrolled in similar postimplantation educational settings, were individually assessed at 6-month intervals over a period of 18 months. Computerized analyses were derived from their spontaneous speech in a 20-min standardized play session. Results for mean length of utterance and vocabulary revealed gradually improving performance for most children, in spite of the generally low starting point. Both measures of production nevertheless remained well below the norms established for normally hearing children. Although the achievement of higher production scores, which underlies more effective interpersonal exchanges, is evident after only 1 year of device use, it is clear that improvement does not always occur at the same pace, as shown by two of the children. This emphasizes the importance of longitudinal studies in documenting intersubject variability and intrasubject stability throughout the experience with an implant.     

Suprasegemental and grammatical control over telegraphic speech in young children

The experiment was designed to test the Brown and Fraser (1963) telegraphic speech hypothesis: that children imitate more content words than function words because of linguistic stress associated with content words in English. Thirty-six children aged 18–36 months were assigned to six treatment groups blocked for linguistic development and were asked to imitate ten simple declarative sentences. In each of five experimental conditions, suprasegmental or grammatical features were systematically manipulated. Results contradicted the Brown and Fraser hypothesis: suprasegmental variables did not influence telegraphic speech production significantly. Imitation strategies were, instead, dependent on grammatical hierarchy.     

How Infants Adapt Speech-Processing Capacities to Native-Language Structure

As infants learn the sound organization of their native language, they use this developing knowledge to make their first attempts to extract the underlying structure of utterances. Although these first attempts fail to capture the full complexity of features that adults use in perceiving and producing utterances, they provide learners with the opportunity to discover additional cues to the underlying structure of the language. Three examples of this developmental pattern are considered: learning the rhythmic organization of the native language, segmenting words from fluent speech, and identifying the correct units of grammatical organization.