The speech of 6 mothers to their healthy infants was examined longitudinally during the neonatal period and at 4, 12, and 24 months in a semi-naturalistic setting. Features of speech analysed were: contour of fundamental frequency, repetitiveness, timing (durations of vocalizations and pauses), tempo and MLU. The neonatal period was characterized by elongated pauses. During the 4-month period the extent of pitch contouring and repetitiveness was greater than at earlier or later ages. By 24 months, the duration of vocalizations and length of MLU became markedly greater. The period of intense face-to-face interaction around the fourth month proved to involve more changes in certain prosodic features. Some of the possible functions of these changes during this phase are discussed.

Words artificially isolated from twelve parents' speech to their children (aged 1; 10–3; 0) were significantly less intelligible to adult listeners than words originally spoken to an adult. This effect holds for randomly sampled words and, to a lesser extent, for matched pairs. While parents did not adjust the clarity of word tokens to the linguistic naiveté of the child listeners, they did adjust intelligibility inversely to the observed predictability of the sampled words in their sentence contexts, and words to children proved more redundant in this sense. The relationship of these findings to other work on the clarity of motherese is examined and the implications for the study of children's speech perception outlined.

Although questions vary considerably with respect to the responses appropriate to them and the motivations intrinsic to them, little attention has yet been given to the potential effects of these factors on the power of questions to perform turn-allocating and response-eliciting functions. The present study attempts to clarify how such variables as motivation, constraint, difficulty and function may affect the child's responsiveness to mother questions. Results suggest that functionally defined question types are differentiable not only by their relative power to elicit a response from the child, but also by the manner in which they are presented. Implications of these results in the context of mother–child conversation and its effects are considered.

The study focuses on the language abilities of 30 20-month-old children, using data from two sources: a detailed maternal interview and 90 minutes of videotaped observation. Observed language was coded into the categories used for the interview. Production and comprehension at 28 months (MLU, PPVT and morphology comprehension) were also assessed. Observation and interview data at 20 months were highly intercorrelated. Cluster analyses of both data sets yielded referential, grammatical morpheme and dialogue clusters, providing partial support for the nominal/pronominal and referential/expressive acquisition styles reported in the literature. However, the referential and grammatical morpheme clusters were highly correlated, suggesting that two acquisition strategies are developing in parallel. Only for those children who heavily emphasize one strategy can one speak of a distinctive style. All interview and observation clusters predicted 28-months MLU, but the grammatical morpheme clusters did not predict later performance on a Grammatical Morpheme Test. It is tentatively suggested that holistic processing strategies underlie the pronominal/expressive style.

Functional and referential changes in maternal speech were investigated in a developmental study of nineteen mother–infant dyads, using video recordings of their free play at three and six months. The role of the infant in influencing speech adjustments was investigated by analysing the relationships between different types of maternal speech and different infant behavioural modes. Three general modes were differentiated – Communicative, Praxic and Other – and, regardless of infant age, mothers were found to make some modifications to their speech style as a function of infant mode. Speech style also was found to change, at a pragmatic level, from three to six months. Both findings support the conclusion that maternal speech is influenced by non-linguistic behavioural ‘feedback’ from infants. However, a finding that affect-oriented speech is more sensitive to infant behaviour than informative speech supports Brown's (1977) contention that the maternal speech register is shaped by two relatively independent interpersonal functions – the affective and communicative components. It is argued that a fuller account of maternal conversational adjustments to prelingual infants requires both a dialogic and a monologic explanation.

The study was designed to investigate 2-month-old infant preferential attention to a feature found to be characteristic of mothers' speech to their infants. A modified infant-control auditory preference paradigm was employed to assess infants' differential attention to synthetically generated and naturally produced rising and falling intonation contours. Analysis of these data revealed that the infants attended more to the rising naturally produced intonation contour. A reverse pattern of greater attention to the falling contour was found with the synthetically generated stimuli. In addition, inspection of the results permitted the conclusion that the infant-control preference paradigm was a viable method for assessing the 2-month-old infant's preferential attention to auditory stimuli. The results are discussed in terms of their relevance to the study of the infant's developing language reception abilities.

Sensitivity to differences in lexical stress pattern was examined in 4- and 5-year-old monolingual French-, German- and Swedish-speaking children. For most stimulus discriminations, the 5-year-olds outperformed their 4-year-old comparison groups. For a discrimination involving a trisyllabic distinction not found in French, however, the French 5-year-olds performed worse than their 4-year-old compatriots, suggesting that the older children had ‘learned’ not to hear the trisyllabic distinction. In follow-up testing of the French 4-year-olds six months later, half of them showed a similar decrease in performance specific to the trisyllabic stimuli. These data support an ‘attunement’ theory of language acquisition, in which potentially relevant abilities that are already partially or fully developed at birth may become attenuated or completely lost if they are inappropriate or irrelevant for the child's language.

A 50-utterance corpus for each of sixteen mothers during caretaking situations (diapering, dressing, bathing) was extracted from in-home tape recordings obtained over a three-day period. The children ranged from 1; 3.15 to 1; 7 and were classified according to Nelson's referential-expressive distinction. A coding scheme consisting of three categories – communicative intent, focus of attention and evaluation – was employed to characterize the mothers' speech. Mothers of referential children produced a greater number of utterances per caretaking incident, more description and less prescriptives than did mothers of expressive children. The findings suggest that Nelson's referential-expressive distinction in child's speech is related to differences in mothers' pragmatic speech characteristics.

Children aged 1; 4 to 1; 6 were asked common what/-questions under four different contextual conditions. The presence of a gesture was found to have a significant effect on the nonverbal components of children's responses, while linguistic sophistication and type of question asked affected vocal responses, but did not produce any consistent effects on nonverbal responses. Results are interpreted as suggesting that, at this early age, gestural information is processed relatively independently of speech. These findings cast doubt on the likelihood that maternal gestures facilitate early language responding. Case-study observations of the children's interactional behaviour with mothers suggest instead that prior experience with verbal routines was a factor in the children's experimental vocal performance.

This study examined mothers' use of fantasy in speech to young children. Observations of mothers in free-play interactions with their 12-to 27-month-old children formed the basis for an analysis of the frequency and type of fantasy relationships encoded in maternal speech. Results suggested that fantasy speech to roughly year-old children was relatively infrequent and restricted to descriptions of the feelings, actions, and functions of animate and inanimate objects. Speech to 1½-year-olds encoded essentially the same fantasy characteristics, but mothers of children in this age group introduced more distinct instances in their fantasy talk. A more notable change occurred in the fantasy utterances directed to 2-year-olds. Mothers of these children talked about non-existent imaginary objects, and often asked the child to extend a play episode by providing a new fantasy element. These findings were discussed in terms of the nature and function of the dyadic interactions in which mothers' fantasy talk occurred.

The present paper investigates a strategy for language acquisition adopted by one child, and the usefulness of book-reading in supporting that strategy. Conversations between this child and his mother around picture-book reading were recorded and recurrent discussions of the same picture were analysed. A coding scheme was devised which identified each speaker's contribution to the exchange of information about a particular picture. By examining recurrent picture discussions, it was possible to trace the child's acquisition of the linguistic means for talking about a given picture. It was found that specific lexical items and constructions used to talk about a picture frequently recurred in subsequent discussions, and that the child learned many of these same items and constructions. Furthermore, he was most likely to acquire what he had heard his mother say about a picture if he had repeated it in an earlier discussion. The usefulness of routines for such situation-specific learning and the implications of the situation-specific approach for future investigations of input language are discussed.

Maternal directives to children aged 10 and 18 months were analysed with respect to both verbal and concomitant nonverbal aspects. The findings emphasize the multimodal nature of mothers' communicative messages and draw attention to the way in which language occurs in an action context and not as an isolated output. No indication was found for this age range that verbal devices come to replace nonverbal ones. At both ages most utterances were accompanied by some form of nonverbal behaviour; the precise nature of the association, however, gives little support to the idea of parallel coding. The child's own behaviour is also shown to form part of the context in which maternal speech takes place.

This study investigated mothers' notions of appropriate speech to 40 children aged 1; 6 to 3; 6. Spontaneous maternal action-directives were analysed in terms of the explicitness with which they expressed syntactic and lexical clues to action-directive intentions. Cross-sectional and longitudinal changes, and progressions within maternal repetition sequences, indicated that the children perceived as most limited in inferential skills elicited the most restricted input. Most of the action-directives they heard could be interpreted non-inferentially, because syntactic and lexical clues to intentions were explicitly expressed. External supports were removed gradually in response to the mother's perception of her child's increasing ability to draw extra-linguistic inferences. Several theoretical models of non-literal speech-act comprehension are supported. It is argued that the differences in language use reflect the mother's notions of the speech a listener is likely to understand.

The influence of frequency of occurrence in input upon early lexical acquisition was examined within an experimental paradigm. Twelve children (1; 0·21 to 1; 3·15) were presented with 16 contrived lexical concepts, each involving a nonsense word and four referents, over ten experimental sessions. Within each concept two exemplars were presented frequently and two were presented infrequently. Overall the children named more frequently presented exemplars than infrequently presented exemplars. However, when the absolute number of presentations was held constant, distributed (infrequent) presentations led to greater acquisition than massed (frequent) presentations.

Mothers' speech in an identification task was examined for ten mother–child pairs in which the child's age varied from 1; 9 to 4; 9. Stimuli were used from three domains, animals, clothes and furniture. These varied in familiarity, centrality (goodness of exemplar) and number of items. Basic-level category terms were found to be the most frequently used labels. Superordinate category terms were elicited by (a) an unfamiliar animal and (b) groups of items from the same domain. Information on category relations was provided in several ways: alternative labels, multiple labels and explicit statements of inclusion. Competencies required to learn the correct referent for category terms and differences among superordinate categories are discussed.

The precise function of imitation in children's speech is still debated. Two hypotheses have been offered that focus on either the progressive nature of imitation to aid in the language acquisition process or the social, conversational role played by imitation in discourse. Support for these positions was sought in the imitations within the speech of a single child at ages 2; 8 and 3; 0. Evidence is presented for both roles of imitation in language acquisition. First, imitation aids in limiting the complexity (MLU) of the language environment. The effects of imitation in this role are compared and contrasted to the effects of the child's productions of what? Also, forms may appear in imitation prior to their appearance in spontaneous speech. A model is proposed in which imitation and what?-responses are overlapping phases of language acquisition which occur prior to spontaneous production of a given form.

The existing data concerning the effects of maternal speech on child language development are so conflicting that it is difficult to draw even tentative conclusions about this relationship. One potential contributor to this problem is our lack of information concerning the determinants of maternal speech. The present study was designed to separate those elements of maternal speech which are heavily influenced by child language levels from those that seem to represent the mother's consistent style or strategy for ‘teaching’ language. Syntactic, discourse, and communicative functions of mothers' speech were examined. Mothers of high-and low-level language children were compared when talking to their daughters and to another girl the same age as their daughter. Analysis indicated a striking amount of similarity and consistency in high vs. low mothers' speech to both their daughters and the other child. Those elements of maternal speech that did show differences tended to be features that are fairly easily monitored by mothers or are directly tied to child utterances.

Samples of the speech addressed by adults to a socially representative sample of 2-year-olds in naturally occurring contexts of interaction were analysed with respect to syntactic, semantic, pragmatic and discourse features to determine which features were most strongly associated with gain by the children on a variety of measures of language development over the ensuing 9 months. Following a principal components analysis of the adult speech variables, the most highly loading variables on the first six components were correlated with children's gain scores. Polar interrogatives, directives and extending utterances were all found to be associated with at least one measure of development. The results are if interpreted as evidence of reciprocal, rather than one-way facilitation.

What does the word chair mean? How does the category of objects bearing this name differ between adults and pre-school children? And how does the knowledge of a possible function of an object affect subjects' judgements? Answers to these questions were sought by means of sorting and rank ordering tasks. Subjects were shown drawings of a variety of objects on which one could sit, and were asked to indicate which ones they would call chairs. Those objects so judged to be category members were rank ordered for degree of typicality (or ‘best example’) by a paired-comparisons procedure. Half the subjects saw drawings of the objects alone, while the others saw a person sitting on each object. The results revealed that adults consistently judged some objects to be better examples than others, and that the provision of function information affected the judgements in a characteristic way. A different, less stable typicality structure was found in the children's category. Function cues caused the children's rank order judgements to change greatly. These findings are discussed within the framework of some recent theories of lexical concept formation in young children, and in relation to recent work on the nature of internal representations.

This study explores factors other than the concept of comparison which influence the learning of specific comparative adjective forms, namely, (a) the nature of the perceptual input, and (b) the nature of the event. Thirty subjects, age 4; 5 to 7; 9, were asked to describe objects reflecting various attribute differences in both multiple-object comparison and single-object, dynamic-change tasks. Children used comparative adjectives to talk about dynamic changes prior to static comparisons, and attributes based on visual or tactile input were easier than those based on both. These results are interpreted as indicating that perceptual cue redundancy and heterogeneity affects the learning of attribute dimensions, and that children first use the -er suffix in a non-comparative sense.