Monthly Archives: December 2008

Coherent discourse solves the pronoun interpretation problem

Many comprehension studies have shown that children as late as age 6 ; 6 misinterpret object pronouns as co-referring with the referential subject about half the time. A recent review of earlier experiments testing children’s interpretation of object pronouns in sentences with quantified subjects (Elbourne, 2005) also suggests that there is a ‘Pronoun Interpretation Problem’. In contrast, two experiments addressing English children’s pronoun production (Bloom, Barss, Nicol & Conway, 1994; de Villiers, Cahillane & Altreuter, 2006) show almost perfect usage. The aim of this study is to verify this asymmetry between pronoun production and pronoun comprehension for Dutch, and to investigate the effects of coherent discourse and topicality on pronoun production and comprehension. Employing a truth-value judgment task and an elicited production task, this study indeed finds such an asymmetry in 83 Dutch children (age range 4 ; 5–6 ; 6). When object pronouns were clearly established as the topic of the target sentence, the Pronoun Interpretation Problem dissolved entirely. These results are compatible with the asymmetrical grammar hypothesis of Hendriks & Spenader (2005/2006) and suggest, contrary to many previous claims, that children are highly proficient at using pragmatic clues in interpretation.

from the Journal of Child Language

Development of prosodic patterns in Mandarin-learning infants

Early prosodic development (f0 variation) was systematically measured in Mandarin-learning infants at the transition from babbling to producing first words. Spontaneous vocalizations of twenty-four infants aged 0 ; 7 to 1 ; 6 were recorded in 45-minute sessions. The speech production of twenty-four caregivers was also audio-recorded during caregiver–infant natural daily interactions at home. All recordings were transcribed using broad prosodic patterns. Analysis revealed four major findings: (1) falling f0 contours were more prominently produced than level and rising contours; (2) high prosodic patterns occurred more frequently than mid and low prosodic patterns; (3) these distribution patterns of f0 contours showed significant similarities in babbling and early words; and (4) these distribution patterns were also similar in infants’ and their caregivers’ data.

from the Journal of Child Language

Early acquisition of gender agreement in the Spanish noun phrase: starting small

Nativist and constructivist accounts differ in their characterization of children’s knowledge of grammatical categories. In this paper we present research on the process of acquisition of a particular grammatical system, gender agreement in the Spanish noun phrase, in children under three years of age. The design of the longitudinal study employed presents some variations in relation to classical studies. The aim was to obtain a large corpus of NP data which would allow different types of analysis of the children’s productions to be carried out. Intra-individual variability in early NP types was analyzed and measured, and an elicitation task for adjectives was used. Results show that the acquisition of NP and gender agreement is a complex process which advances as the children gradually integrate different pieces of evidence: phonological, distributional and functional. The reduction of variability as the grammatical process advances is a key feature for its explanation.

from the Journal of Child Language

How the parts relate to the whole: Frequency effects on children’s interpretations of novel compounds

This study explores different frequency effects on children’s interpretations of novel noun–noun compounds (e.g. egg bag as ‘bag FOR eggs’). We investigated whether four- to five-year-olds and adults use their knowledge of related compounds and their modifier–head relations (e.g. sandwich bag (FOR) or egg white (PART-OF)) when explaining the meaning of novel compounds and/or whether they are affected by overall frequency of modifier–head relations in their vocabulary. Children’s interpretations were affected by their experience with relations in compounds with the same head, but not by overall relation frequency. Adults’ interpretations were affected by their experience with relations in compounds with the same modifier, suggesting that children and adults use similar but different knowledge to interpret compounds. Furthermore, only children’s interpretations revealed an overuse of visually perceivable relations.

from the Journal of Child Language

Korean- and English-speaking children use cross-situational information to learn novel predicate terms

This paper examines children’s attention to cross-situational information during word learning. Korean-speaking children in Korea and English-speaking children in the US were taught four nonce words that referred to novel actions. For each word, children saw four related events: half were shown events that were very similar (Close comparisons), half were shown events that were not as similar (Far comparisons). The prediction was that children would compare events to each other and thus be influenced by the events shown. In addition, children in these language groups could be influenced differently as their verb systems differ. Although some differences were found across language, children in both languages were influenced by the type of events shown, suggesting that they are using a comparison process. Thus, this study provides evidence for comparison, a new mechanism to describe how children learn new action words, and demonstrates that this process could apply across languages.

from the Journal of Child Language

Language skills in shy and non-shy preschoolers and the effects of assessment context

Nineteen shy, twenty-three middle and twenty-five non-shy junior kindergarten children were assessed at school by an unfamiliar examiner, and at home where their parents administered a parallel form of the expressive and receptive vocabulary tests given at school. A speech sample between the child and parent was also collected at home. Shy children spoke less than non-shy and middle children at home. Additionally, the parents of shy children spoke less than parents of non-shy children. Although there were no language differences between the groups, results showed a context effect for expressive vocabulary, in that all groups of children scored higher at school. The pattern of results suggests that previously observed language differences found between shy and non-shy children are not robust, and that testing children at school does not negatively impact their performance.

from the Journal of Child Language

The perfective past tense in Greek child language

This study examines the perfective past tense of Greek in an elicited production and an acceptability judgment task testing 35 adult native speakers and 154 children in six age groups (age range: 3 ; 5 to 8 ; 5) on both existing and novel verb stimuli. We found a striking contrast between sigmatic and non-sigmatic perfective past tense forms. Sigmatic forms (which have a segmentable perfective affix (-s-) in Greek) were widely generalized to different kinds of novel verbs in both children and adults and were overgeneralized to existing non-sigmatic verbs in children’s productions. By contrast, non-sigmatic forms were only extended to novel verbs that were similar to existing non-sigmatic verbs, and overapplications of non-sigmatic forms to existing sigmatic verbs were extremely rare. We argue that these findings are consistent with dual-mechanism accounts of morphology.

from the Journal of Child Language

The prosodic (re)organization of children’s early English articles

Researchers have long been puzzled by children’s variable omission of grammatical morphemes, often attributing this to a lack of semantic or syntactic competence. Recent studies suggest that some of this variability may be due to phonological constraints. This paper explored this issue further by conducting a longitudinal study of five English-speaking one- to two-year-olds’ acquisition of articles. It found that most children were more likely to produce articles when these could be produced as part of a disyllabic foot. However, acoustic analysis revealed that one child initially produced all articles as independent prosodic words. These findings confirm that some of the variable production of articles is conditioned by constraints on children’s early phonologies, providing further support for the Prosodic Licensing Hypothesis. They also hold important implications for our understanding of the emergence of syntactic knowledge.

from the Journal of Child Language

The structure and nature of phonological neighbourhoods in children’s early lexicons

This research examines phonological neighbourhoods in the lexicons of children acquiring English. Analyses of neighbourhood densities were done on children’s earliest words and on a corpus of spontaneous speech, used to measure neighbours in the target language. Neighbourhood densities were analyzed for words created by changing segments in word-onset position (rhyme neighbours as in pin/bin), vowel position (consonant neighbours as in pin/pan/) and word-offset position (lead neighbours as in pin/pit). Results indicated that neighbours in children’s early lexicons are significantly more often distinguished in word-onset position (rhyme neighbours) and significantly less often distinguished in word-offset position (lead neighbours). Moreover, patterns in child language are more extreme than in the target language. Findings are discussed within the PRIMIR framework (Processing Rich Information from Multidimensional Interaction Representations; Werker & Curtin, 2005). It is argued that early perceptual sensitivity aids lexical acquisition, supporting continuity across speech perception and lexical acquisition.

from the Journal of Child Language

‘The Adventure’: Charles-Ferdinand Ramuz’s Extraordinary Stroke Diary

The famous Swiss writer Charles-Ferdinand Ramuz suffered a stroke at 65 years, which he called ‘the adventure’ or ‘the accident’. He developed language disturbances suggesting crossed aphasia in a right hander with left hemiparesis. This uncommon pattern allowed him to continue to write his diary and to report his disturbances, with a unique depth and precision, especially for cognitive-emotional changes. Language and motor dysfunction recovered within a few weeks, but Ramuz complained of persisting emotional flattening alternating with irritability, fatigue, depression, anxiety, and concentration difficulty, which gave him the feeling to have become another person and to be inhabited by a stranger, whom he compared with devils. Ramuz fought several months to resume his literary activity, having the impression to have lost inspiration and creativity. However, the novels he wrote less than 6 months after stroke show no stylistic changes and have been found to be of the same quality as his previous production. Ramuz even ‘used’ his stroke experience in his work, in particular in a novel depicting an old man who has a stroke and dies of it. Ramuz’s diary, with his own daily description of stroke features and consequences during acute and recovery phases, is a unique document in a writer of his importance, and provides invaluable information on subjective emotional and cognitive experience of stroke.

from European Neurology

On-line processing of tense and temporality in agrammatic aphasia

Agrammatic aphasic individuals exhibit marked production deficits for tense morphology. This paper presents three experiments examining whether a group of English-speaking agrammatic individuals (n = 10) exhibit parallel deficits in their comprehension of tense. Results from two comprehension experiments (on-line grammaticality judgment studies) suggest that these individuals are impaired for tense comprehension, and furthermore that their deficit is more pronounced for morphosemantic rather than morphosyntactic aspects of tense processing. Results from a third experiment (an elicited production study) indicate that these individuals exhibit parallel production and comprehension impairments for tense. Across the three experiments, the consistent pattern was that of a significant difficulty in associating verb forms with a pre-specified temporal context when compared to all other processes. Implications for current models of agrammatic tense and morphological deficits are discussed.

from Brain and Language

Middle ear disease in children with cleft palate: Protocols for management

Objective
There is wide international variation in the protocols used for middle ear disease management in cleft palate patients. Ventilation tube (grommet) insertion may occur routinely at the time of palatoplasty or selectively on a separate occasion if symptomatic middle ear disease develops. The audiological and otologic outcomes of cleft palate patients were studied in a single institution over a timeframe in which both protocols were utilised.

Methods
This was a retrospective study of 234 cleft palate patients who underwent palatoplasty from 1990 to 2005 at Middlemore Hospital, Auckland, New Zealand. Data on hearing loss, middle ear disease, and tympanic membrane abnormalities was collected from clinical notes. Audiological data was obtained from pure tone audiogram reports.

Results
Forty-five patients had routine grommets inserted concurrent with palatoplasty and 189 patients were managed conservatively with selective grommet insertion if indicated. Grommets were subsequently required in 79 (41.8%) of these 189 patients. There was no difference in the incidence of persistent conductive hearing loss, but recurrent middle ear disease, tympanic membrane abnormalities, and the total number of grommet insertions were significantly higher in the routine grommet group. Poorer outcomes were noted in patients who had undergone a greater number of grommet insertions.

Conclusion
No significant deterioration in audiological outcomes and better otologic outcomes were found in cleft palate patients undergoing selective grommet insertion compared to routine grommet insertion. It is recommended that ventilation tube placement occur in patients selected on the basis of symptomatic infection or significant hearing loss.

from the International Journal of Pediatric Otorhinolaryngology

Semicircular canal dehiscence in the pediatric population

Objectives
(1) Identify the existence of semicircular canal bony dehiscence in the pediatric population; (2) determine the frequency of this finding in children over 3 years of age who have had temporal bone computed tomography (CT) imaging; (3) correlate the clinical history and audiological data to CT findings in this population.

Design and setting
Retrospective review of temporal bone CT scans performed at a tertiary care children’s hospital and retrospective chart review.

Patients
Children over 3 years of age who underwent a temporal bone CT scan between January 2006 and December 2006.

Results
Review of 131 temporal bone CT scans using multiplanar imaging techniques revealed evidence of semicircular canal bony dehiscence in 18 children older than 3 years of age. Dehiscence of the superior semicircular canal was identified in 14 patients while dehiscence of the posterior semicircular canal was identified in 5 patients. One patient had both the superior and posterior semicircular canal dehiscences. Retrospective chart review comparing children with and without semicircular canal dehiscence showed no significant difference in clinical history or audiological data.

Conclusions
Semicircular canal dehiscence exists in the pediatric population. In this series, 18 of 131 temporal bone CT scans were positive for bony dehiscence of the superior or posterior semicircular canals. Further study is required to determine the clinical significance of this radiographic finding.

from the International Journal of Pediatric Otorhinolaryngology

Cognition in healthy aging is related to regional white matter integrity, but not cortical thickness

It is well established that healthy aging is accompanied by structural changes in many brain regions and functional decline in a number of cognitive domains. The goal of this study was to determine (1) whether the regional distribution of age-related brain changes is similar in gray matter (GM) and white matter (WM) regions, or whether these two tissue types are affected differently by aging, and (2) whether measures of cognitive performance are more closely linked to alterations in the cerebral cortex or in the underlying WM in older adults (OA). To address these questions, we collected high-resolution magnetic resonance imaging (MRI) data from a large sample of healthy young adults (YA; aged 18–28) and OA (aged 61–86 years). In addition, the OA completed a series of tasks selected to assess cognition in three domains: cognitive control, episodic memory, and semantic memory. Using advanced techniques for measuring cortical thickness and WM integrity, we found that healthy aging was accompanied by deterioration of both GM and WM, but with distinct patterns of change: Cortical thinning occurred primarily in primary sensory and motor cortices, whereas WM changes were localized to regions underlying association cortices. Further, in OA, we found a striking pattern of region-specific correlations between measures of cognitive performance and WM integrity, but not cortical thickness. Specifically, cognitive control correlated with integrity of frontal lobe WM, whereas episodic memory was related to integrity of temporal and parietal lobe WM. Thus, age-related impairments in specific cognitive capacities may arise from degenerative processes that affect the underlying connections of their respective neural networks.

from Neurobiology of Aging

Contrast of hand preferences between communicative gestures and non-communicative actions in baboons: Implications for the origins of hemispheric specialization for language

Gestural communication is a modality considered in the literature as a candidate for determining the ancestral prerequisites of the emergence of human language. As reported in captive chimpanzees and human children, a study in captive baboons revealed that a communicative gesture elicits stronger degree of right-hand bias than non-communicative actions. It remains unclear if it is the communicative nature of this manual behavior which induces such patterns of handedness. In the present study, we have measured hand use for two uninvestigated behaviors in a group of captive olive baboons: (1) a non-communicative self-touching behavior (“muzzle wipe” serving as a control behavior), (2) another communicative gesture (a ritualized “food beg”) different from the one previously studied in the literature (a species-specific threat gesture, namely “hand slap”) in the same population of baboons. The hand preferences for the “food beg” gestures revealed a trend toward right-handedness and significantly correlated with the hand preferences previously reported in the hand slap gesture within the same baboons. By contrast, the hand preferences for the self-touching behaviors did not reveal any trend of manual bias at a group-level nor correlation with the hand preferences of any communicative gestures. These findings provide additional support to the hypothesized existence in baboons of a specific communicative system involved in the production of communicative gestures that may tend to a left-hemispheric dominance and that may differ from the system involved in purely motor functions. The hypothetical implications of these collective results are discussed within the theoretical framework about the origins of hemispheric specialization for human language.

from Brain and Language