Canonical syllables may be important units in early speech perception as well as production. Twenty infants (mean age 51 hours) (and twenty controls) were tested for their ability to discriminate between members of syllable pairs which were either canonical (pæt and tæp) or non-canonical (pst and tsp). A discrimination learning method was used in which syllables signalled the availability of either a recording of the mother's voice or silence – one of which was presented if the infant began a sucking burst. Infants in the canonical condition changed sucking patterns during signals over an 18-minute experimental session and activated their mother's voice more than silence, consistent with previous experiments using mother's voice as a reinforcer. In the non-canonical condition, infants also changed sucking patterns but sucked more during the signal for quiet than mother's voice, contrary to previous findings. Differential sucking during the syllables indicated discrimination in both conditions, but infants responded differently depending upon whether the syllables were canonical or non-canonical. The activation of silence in the non-canonical condition may be the result of a preference for quiet, but it is better explained as a failure to progress to a level of differential responding that was reached by the canonical group.

The utterances of one French and one American infant at 0;5, 0;8, 0;11, and 1;2 were transcribed and acoustically analysed for syllable duration and vowel formant values. Both general and language-specific effects emerged in the longitudinal study. Initial similarities in the consonantal repertoires of both infants, increasing control in producing target F1 and F2 values, and developmental changes in babbling characteristics over time seem to reflect universal patterns. Yet the babbling of the infants differed in ways that appear to be due to differences in their language environments. Shifts in the infants' sound repertoires reflected phoneme frequencies in the adult languages. The English-learning infant produced more closed syllables, which is characteristic of English, than the French-learning infant. The French-learning infant tended to produce more regularly-timed nonfinal syllables and showed significantly more final-syllable lengthening (both characteristic of French) than the English-learning infant.

Three Canadian–English infants and three Parisian–French infants were filmed bi-weekly for three to five months, from the age of 0;9 or 0;11 until 1;2, at home in naturalistic interaction with a parent. Their babbled utterances were transcribed phonetically and categorized according to consonant-type and vowel-type. The contexts for each utterance were described in terms of both specific and more general contextual categories. Observed frequencies of co-occurrences between phonetic and contextual categories were compared to expected frequencies, and deviations were considered to be patterns in babbling. Patterning increased after age 1;0 for most infants, and from 15% to 30% of each infant's babbled utterances recurred in particular contexts with a greater-than-expected frequency. Similarities in patterns were found both within and across language groups. These sound-meaning correspondences in babbling are viewed as continuous with early situation-bound meaning in words.

This study examines the relationship between maternal-report measures of referential vocabulary and observational measures of referential vocabulary and usage in eight first-born middle-class children at 50 and loo words. The results indicate that although maternal-report measures of vocabulary composition can be reasonably reliable, provided some attempt is made to restrict variation in the number of vocabulary items upon which they are based, such measures tend to exaggerate the relative importance of common nouns for the child in two ways; firstly, in the sense that they reflect differential maternal sensitivity to such word-types in comparison with other less-‘referential’ items; and, secondly, in the sense that they overestimate the extent to which such word-types actually occur in the child's spontaneous speech.

The reported study investigated the relation between children's single-word utterances and maternal single-word utterances expressing similar communicative intents. Twenty-four Hebrew-speaking dyads (the children about 1;6) were videotaped for 30 min in an unstructured session. Single-word utterances were analysed for their communicative intent and the relationship of the expression to the underlying intent was defined in the form of realization rules. Of 17,471 child utterances, 97·0% were realizations that were also used by mothers for expressing the same communicative intent. The most frequently modelled rule for an intent had the highest chance of being adopted by children, and the probability sharply decreased for the relatively less frequently modelled rules. The results suggest that children's single-word utterances are similar to, and probably learned from, single-word utterances of caretakers expressing the same specific communicative intents.

The present paper reports a case-study of a normally developing boy who made pronominal errors for about ten months. Comprehension and production of first- and second-person pronouns were longitudinally examined from 1; 7 to 2; 10 to test three hypotheses concerning pronominal errors: pronominal errors are a result of either (a) semantic confusion, (b) simple imitation, or (c) confusion between self and others. The results showed that the child began using first- and second-person pronouns at about 1; 8 and mastered the correct usage by 2; 10. Consistent errors for the first- and the second-person pronouns were observed from 1; 11 to 2; 4, but proportions of errors occurring in his imitative language were low. The comprehension and production data clearly indicated that the child persistently made pronominal errors due to semantic confusion. That is, first-person pronouns referred to a person with whom the child conversed and second-person pronouns referred to himself.

Recent treatments of the optionality of sentence subjects in young-children's English have sought to link this phenomenon, and its eventual demise, to the development of the child's verb inflection system or to a parameter-resetting within the INFL (‘inflection’) constituent of the child's grammar. It is claimed that subject optionality disappears when these developments occur. The case-study reported here investigated the productive language of an English child between 2;5 and 3;0. It found that subjects were no longer optional at a stage when none of the reflexes of INFL claimed in the literature to be associated with the disappearance of subject optionality had yet been acquired. The possibility that subjects were present only when communicatively required was rejected. The frequency of subject realization of a Japanese child aged 3;0 was used to provide a measure of expected realization when subjects are not grammatically required. It is concluded that subject obligatoriness in English may be acquired as a characteristic of the language sui generis, independently of developments elsewhere in the child's emerging grammar.

Although preschoolers typically accept the basic level label for an object (e.g. dog) and tend to resist all others (e.g. collie, animal), this tendency is not inviolable. Under certain circumstances, children accept more than one label per object. In this experiment, with 20 three- and 20 four-year-old children, we extended this body of research in three ways. We examined (1) children's production of multiple, hierarchically related labels; (2) the pragmatic consequences of the inherent asymmetry of inclusion relations; and (3) the influence of morphology (modifier + noun constructions vs. simple lexemes) at the subordinate level. Children labelled objects most frequently at the basic level, but also readily produced many non-basic level terms. Children, like adults, may prefer to label objects at the basic level, but they exhibit no general prohibition against also labelling at other, non-basic levels. Their performance challenges the notion that the ability to label objects flexibly at multiple levels is beyond the young child's capacity.

This study examined five- to seven-year-olds' assumptions about the experiential connotation of ‘I know that's X’. In Experiment 1 children tried to identify which of a set of unfamiliar targets had a given name (X), and after they had chosen, we enquired either whether they KNEW their chosen item was (X) or whether they were SURE. Six- to seven-year-olds (N = 39) judged that they were sure more often than they judged that they knew, which suggests that although they experienced confidence that they had chosen correctly, they assumed it would be inappropriate to judge ‘know’, because this would imply an experiential basis, which was absent. Five- to six-year-olds (N = 36) did not discriminate between the two kinds of question. In Experiment 2, children could infer which item was a named unfamiliar cartoon character by ruling out familiar distractors. Six- to seven-year-olds (N = 35) judged that they knew they had picked the right one much more often than they judged that they knew their chosen picture was (target name). Again, five- to six-year-olds (N = 44) did not discriminate between the two kinds of question. This demonstrates powerfully that the older children held an experiential connotation of ‘I know that's X’, since they avoided such judgements even when they knew by inference they had chosen correctly.

Explicit verbal comparisons in 53 popular children's books were syntactically and semantically classified. Comparison types found in these books were contrasted with comparisons used as comprehension stimuli in extant developmental research. Although noun-phrase metaphor has been a popular syntactic form in research, it is a rare form in children's literature. Implications for the design of future stimulus sets are discussed.