Thai Speech and Language Test for children between 1 and 2 years of age

from the International Journal of Language and Communication Disorders

Background: Children with delayed speech and language development are at considerable risk for later language impairment, social and behavioural problems, and illiteracy. Early diagnosis is needed for intervention planning and prevention. However, a speech and language test for Thai children has not been available.

Aims: To establish a Thai Speech and Language Test for Thai children between zero and 2 years of age.

Methods & Procedures: The authors reviewed both Thai and international speech and language development tests and studies related to factors associated with speech and language development. A Thai Speech and Language Test for children between zero and 2 years of age (TSLT2) was then formulated. The test was used with 419 typically developing Thai children in Khon Kaen, north-east Thailand.

Outcome & Results: Language quotients were calculated to quantify/qualify Thai language development norms. Inter-rater reliability of the test ranged between 0.64 and 1, while internal consistencies ranged between 0.83 and 0.95 for tests on children between 1 and 2 years of age.

Conclusions: Professionals or paraprofessionals can use the Thai Speech and Language Test for children between 1 and 2 years of age, which is the first Thai tool for the assessment, diagnosis and remediation planning of children with delayed speech and language development. It should be also adapted for use in other regions in Thailand. However, the test for children aged between 3 and 9 months should be revised and continue to be developed.

Uses and interpretations of non-word repetition tasks in children with and without specific language impairments (SLI)

from the International Journal of Language and Communication Disorders

Background: The non-word repetition task (NRT) has gained wide acceptance in describing language acquisition in both children with normal language development (NL) and children with specific language impairments (SLI). This task has gained wide acceptance because it so closely matches the phonological component of word learning, and correlates with measures of phonological working memory, a deficit in which is hypothesized to underlie SLI.

Aims/Methods & Procedures: Recent uses of the NRT seem to accept it as a measure of phonological working memory capacity in spite of the fact that researchers have consistently acknowledged that the task taps many language processes, including speech perception, phonological encoding, phonological memory, phonological assembly and articulation. This paper reviews the literature on the use of the non-word repetition task (NRT) in children with NL and children with SLI, emphasizing the component skills necessary for successful repetition.

Main Contribution: For children with NL, discussion has focused on (1) the relationship between non-word repetition ability and vocabulary, and (2) lexical and sublexical influences on repetition accuracy. For children with SLI, discussion has focused on these factors as well, but has also considered other component skills that support non-word repetition. Researchers have examined speech perception and discrimination, phonological encoding, phonological memory, phonological assembly, motor planning, and articulation, and have found evidence that children with SLI exhibit impairments in each of these supporting skills.

Conclusions: Because repetition accuracy depends on lexical and sublexical properties, the NRT can be used to examine the structural properties of the lexicon in both children with NL and with SLI. Further, because the task taps so many underlying skills, it is a powerful tool that can be used to identify children with language impairments.

Auditory event perception: The source-perception loop for posture in human gait

from Perception and Psychophysics

There is a small but growing literature on the perception of natural acoustic events, but few attempts have been made to investigate complex sounds not systematically controlled within a laboratory setting. The present study investigates listeners’ ability to make judgments about the posture (upright-stooped) of the walker who generated acoustic stimuli contrasted on each trial. We use a comprehensive three-stage approach to event perception, in which we develop a solid understanding of the source event and its sound properties, as well as the relationships between these two event stages. Developing this understanding helps both to identify the limitations of common statistical procedures and to develop effective new procedures for investigating not only the two information stages above, but also the decision strategies employed by listeners in making source judgments from sound. The result is a comprehensive, ultimately logical, but not necessarily expected picture of both the source-sound-perception loop and the utility of alternative research tools.

The auditory continuity illusion: A parametric investigation and filter model

from Perception and Psychophysics

A sound that is briefly interrupted by a silent gap is perceived as discontinuous. However, when the gap is filled with noise, the sound may be perceived as continuing through the noise. It has been shown that this continuity illusion depends on the masking of the omitted target sound, but the underlying mechanisms have yet to be quantified thoroughly. In this article, we systematically quantify the relation between perceived continuity and the duration, relative power, or notch width of the interrupting broadband noise for interrupted and noninterrupted amplitude-modulated tones at different frequencies. We fitted the psychometric results in order to estimate the range of the noise parameters that induced auditory grouping. To explain our results within a common theoretical framework, we applied a power spectrum model to the different masking results and estimated the critical bandwidth of the auditory filter that may be responsible for the continuity illusion. Our results set constraints on the spectral resolution of the mechanisms underlying the continuity illusion and provide a stimulus set that can be readily applied for neurophysiological studies of its neural correlates.

Communicative spontaneity of children with autism

from Autism

The communicative spontaneity of children with autism who had limited spoken language in their natural environment was investigated. This naturalistic observation is a preliminary study using a continuum model to describe the nature of communicative spontaneity. The results indicate that the level of communicative spontaneity in the natural environment varied (1) along a continuum, (2) across communicative forms, functions, activities, partners and consequences, and (3) across the effectiveness of requesting and rejecting functions. The findings from this study may provide some directions for future study.

How do people with aphasia view their discharge from therapy?

from Aphasiology

Background: The aphasiology literature contains very little on how therapy ends. However, the events surrounding discharge are complex and are an integral part of therapy as a whole.

Aims: This article focuses on how people with aphasia view their discharge from therapy in order to shed some light on this rarely explored issue.

Methods & Procedures: This research is based on the results of a larger qualitative study that explored the experiences of treatment termination for both clients and speech pathologists. This paper draws on in-depth interviews with 21 people with aphasia and 16 family members. Data collection and analysis were carried out using principles and techniques of grounded theory.

Outcomes & Results: Interviewees’ narratives of discharge reflected three broad influences: their biographies, their notions of recovery, and their feelings about their aphasia therapy. This paper summarises interviewees’ perceptions on why they were discharged, how it happened, and how they felt about it.

Conclusions: Despite the individual circumstances of each person’s account, a common finding was uncertainty and confusion surrounding discharge. Clients were not always sure why therapy ended. They rarely discussed it with their therapists in much depth and often felt unable to question their therapists’ decisions. This paper argues that such findings reflect the disempowered position of our clients with aphasia and that a more open, shared process of decision making would not only be more satisfactory for all parties but also demonstrate better outcomes of therapy itself.

Boundary alignment enables 11-month-olds to segment vowel initial words from speech

from the Journal of Child Language

Past research has indicated that English-learning infants begin segmenting words from speech by 7·5 months of age (Jusczyk & Aslin, 1995). More recent work has demonstrated, however, that 7·5-month-olds’ segmentation abilities are severely limited. For example, the ability to segment vowel-initial words from speech reportedly does not appear until 13·5 to 16 months of age (Mattys & Jusczyk, 2001; Nazzi, Dilley, Jusczyk, Shattuck-Hufnagel & Jusczyk, 2005). In this paper, we report on three experiments using the Headturn Preference procedure that investigate both phonetic and phonological factors influencing 11-month-olds’ segmentation of vowel-initial words from speech. We replicate earlier findings suggesting that infants have difficulty segmenting vowel-initial words from speech. In addition we extend these findings by demonstrating that under certain conditions, infants are capable of segmenting vowel-initial words from speech at a much younger age than earlier studies have reported. Our findings suggest that infants’ ability to segment vowel-initial words from speech is tightly constrained by acoustic-phonetic factors such as pitch movement at the onset of vowel-initial words and segmental strengthening. These experiments underscore the complexity of early word segmentation, and highlight the importance of including contextual factors in developmental models of word segmentation.

Child-directed speech: relation to socioeconomic status, knowledge of child development and child vocabulary skill

from the Journal of Child Language

This study sought to determine why American parents from different socioeconomic backgrounds communicate in different ways with their children. Forty-seven parent–child dyads were videotaped engaging in naturalistic interactions in the home for ninety minutes at child age 2 ; 6. Transcripts of these interactions provided measures of child-directed speech. Children’s vocabulary comprehension skills were measured using the Peabody Picture Vocabulary Test at 2 ; 6 and one year later at 3 ; 6. Results indicate that: (1) child-directed speech with toddlers aged 2 ; 6 predicts child vocabulary skill one year later, controlling for earlier toddler vocabulary skill; (2) child-directed speech relates to socioeconomic status as measured by income and education; and (3) the relation between socioeconomic status and child-directed speech is mediated by parental knowledge of child development. Potential mechanisms through which parental knowledge influences communicative behavior are discussed.

Conveying information about adjective meanings in spoken discourse

from the Journal of Child Language

This study examined information about adjective meanings available in adults’ spoken discourse in the original 27 CHILDES corpora of typically developing English-speaking children. In order to increase the probability that adjectives would be novel to children to whom they were addressed, only rare adjectives were examined (those that occurred 5 times in the corpus, N=878). Contexts surrounding adjectives (±3 utterances on either side of the target) were scored for linguistic clues to meaning, including related language, compare/contrast and evaluative information. Linguistic contexts contained more information in adult–child conversations than in adult–adult conversations. There were differences among information categories. For example, explicit definitions were relatively rare compared to other types of information and were far less frequent than reported in structured laboratory situations. Findings highlight the importance of looking at adult input in situations where teaching word meaning is not an explicit goal.

Factors accounting for the ability of children with SLI to learn agreement morphemes in intervention

from the Journal of Child Language

The aim of this study was to uncover factors accounting for the ability of children with specific language impairment (SLI) to learn agreement morphemes in intervention. Twenty-five children with SLI who participated in a six-month intervention program focused on teaching third person singular -s or auxiliary is/are/was showed a wide range of use of the target morpheme after intervention. Regression analyses showed that age and two factors expected to be related to agreement – the use of noun plural -s and subject/verb constructions prior to intervention – significantly predicted progress in the acquisition of agreement morphemes. In contrast, the pretreatment use of morphemes hypothesized to be unrelated to agreement was not a significant predictor of progress. The results indicate that the ability of children with SLI to learn agreement morphemes relies on their prior ability to use noun plural and subject/verb constructions.

Infant gaze following and pointing predict accelerated vocabulary growth through two years of age: a longitudinal, growth curve modeling study

from the Journal of Child Language

We found that infant gaze following and pointing predicts subsequent language development. At ages 0 ; 10 or 0 ; 11, infants saw an adult turn to look at an object in an experimental setting. Productive vocabulary was assessed longitudinally through two years of age. Growth curve modeling showed that infants who gaze followed and looked longer at the target object had significantly faster vocabulary growth than infants with shorter looks, even with maternal education controlled; adding infant pointing strengthened the model. We highlight the role of social cognition in word learning and emphasize the communicative-referential functions of early gaze following and pointing.

Intentions help children learn meaningful rules

from the Journal of Child Language

The present study investigated the roles of pattern detection capacities and understanding of intentions in children’s learning of linguistic rules. We taught two-year-olds a Hebrew morphological distinction between noun and verb forms using two different training protocols. The protocols were identical in all parameters except that only in an Intentional, but not in a Control condition, were children introduced to the stimuli in an intentional communicative context. We found that children learned the morphological rule only in the Intentional condition. Thus, besides their pattern detection capacities, children’s understanding of intentions substantially boosts their learning of meaningful rules.

Perseverant responding in children’s picture naming

from the Journal of Child Language

Two groups of children were given pictures of animals to name as quickly as they could. The groups comprised 40 nursery aged children (mean age 3 ; 11) and 40 Year 2 children (mean age 6 ; 9) attending primary school in London. The 30 animals were presented one by one, on cards, and any errors made by the children were noted. Consistent with a similar object naming study with adults (Vitkovitch, Kirby & Tyrrell, 1996) and a study with children (Gershkoff-Stowe, 2002), picture naming errors referred to earlier named objects. However, while adults showed below-chance interference from objects that had only just been named (Lag 1), children were most susceptible to interference from very recently named objects (see also Gershkoff-Stowe, 2002). Furthermore, the proportion of younger children making Lag 1 errors was higher than the proportion of older children making Lag 1 errors. The results are discussed in relation to the activation levels of lexical representations.

Prosodically-conditioned variability in children’s production of French determiners

from the Journal of Child Language

Researchers have long noted that children’s grammatical morphemes are variably produced, raising questions about when and how grammatical competence is acquired. This study examined the spontaneous production of determiners by two French-speaking children aged 1 ; 5–2 ; 5. It found that determiners were produced earlier with monosyllabic words, and later with disyllabic and trisyllabic words. This suggests that French-speaking children’s early determiners are prosodically licensed as part of a binary foot, with determiners appearing more consistently only once prosodic representations become more complex. This study therefore provides support for the notion that grammatical morphemes first appear in prosodically licensed contexts, suggesting that some of the early variability in morphological production is systematic and predictable.

Reliability and validity of the Computerized Comprehension Task (CCT): data from American English and Mexican Spanish infants

from the Journal of Child Language

Early language comprehension may be one of the most important predictors of developmental risk. The need for performance-based assessment is predicated on limitations identified in the exclusive use of parent report and on the need for a performance measure with which to assess the convergent validity of parent report of comprehension. Child performance data require the development of procedures to facilitate infant attention and compliance. Forty infants (20 at 1 ; 4 and 20 at 1 ; acquiring English completed a standard picture book task and the same task was administered on a touch-sensitive screen. The computerized task significantly improved task attention, compliance and performance. Reliability was high, indicating that infants were not responding randomly. Convergent validity with parent report and 4-month stability was substantial. Preliminary data extending this approach to Mexican-Spanish are presented. Results are discussed in terms of the promise of this technique for clinical and research settings and the potential influences of cultural factors on performance.