Joanna Atkinson

Identifying specific language impairment in deaf children acquiring British Sign Language: Implications for theory and practice

This paper presents the first ever group study of specific language impairment (SLI) in users of sign language. A group of 50 children were referred to the study by teachers and speech and language therapists. Individuals who fitted pre-determined criteria for SLI were then systematically assessed. Here, we describe in detail the performance of 13 signing deaf children aged 5-14 years on normed tests of British Sign Language (BSL) sentence comprehension, repetition of nonsense signs, expressive grammar and narrative skills, alongside tests of non-verbal intelligence and fine motor control. Results show these children to have a significant language delay compared to their peers matched for age and language experience. This impaired development cannot be explained by poor exposure to BSL, or by lower general cognitive, social, or motor abilities. As is the case for SLI in spoken languages, we find heterogeneity within the group in terms of which aspects of language are affected and the severity of the impairment. We discuss the implications of the existence of language impairments in a sign language for theories of SLI and clinical practice.

Exploring the perceptual characteristics of voice-hallucinations in deaf people

Introduction. Previous research has not taken account of the possibility that deaf people will show greater heterogeneity in how they experience voice-hallucinations due to individual differences in experience with language and residual hearing. This study aims to explore how deaf participants perceive voice-hallucinations and whether the perceptual characteristics reported reflect individual experience with language and sensory input. Method. A statement-sorting task generated data about perceptual characteristics of voice-hallucinations for exploratory factor analysis. The sample included 27 deaf participants with experience of voice-hallucinations, and a range of hearing loss and language backgrounds. Results. Perceptual characteristics of voice-hallucinations map closely onto individual auditory experience. People born profoundly deaf loaded onto nonauditory factors. Deaf people with experience of hearing speech, through residual hearing, hearing aids, or predeafness experience, reported auditory features or uncertainty about mode of perception. Conclusions. This is the first study to systematically explore voice-hallucinations in deaf people and to advance a model of subvocal articulation to account for such counterintuitive phenomena.

Modality-Dependent and -Independent Factors in the Organisation of the Signed Language Lexicon: Insights From Semantic and Phonological Fluency Tasks in BSL

We used fluency tasks to investigate lexical organisation in Deaf adults who use British sign language (BSL). The number of responses produced to semantic categories did not differ from reports in spoken languages. However, there was considerable variability in the number of responses across phonological categories, and some signers had difficulty retrieving items. Responses were richly clustered according to semantic and/or phonological properties. With respect to phonology, there was significantly more clustering around the parameters “handshape” and “location” compared to “movement”. We conclude that the BSL lexicon is organised in similar ways to the lexicons of spoken languages, but that lexical retrieval is characterised by strong links between semantics and phonology; movement is less readily retrieved than handshape and location; and phonological fluency is difficult for signers because they have little metaphonological awareness in BSL and because signs do not display the onset salience that characterises spoken words.

Deaf children's non-verbal working memory is impacted by their language experience

Several recent studies have suggested that deaf children perform more poorly on working memory tasks compared to hearing children, but these studies have not been able to determine whether this poorer performance arises directly from deafness itself or from deaf childrens reduced language exposure. The issue remains unresolved because findings come mostly from (1) tasks that are verbal as opposed to non-verbal, and (2) involve deaf children who use spoken communication and therefore may have experienced impoverished input and delayed language acquisition. This is in contrast to deaf children who have been exposed to a sign language since birth from Deaf parents (and who therefore have native language-learning opportunities within a normal developmental timeframe for language acquisition). A more direct, and therefore stronger, test of the hypothesis that the type and quality of language exposure impact working memory is to use measures of non-verbal working memory (NVWM) and to compare hearing children with two groups of deaf signing children: those who have had native exposure to a sign language, and those who have experienced delayed acquisition and reduced quality of language input compared to their native-signing peers. In this study we investigated the relationship between NVWM and language in three groups aged 6–11 years: hearing children (n = 28), deaf children who were native users of British Sign Language (BSL; n = 8), and deaf children who used BSL but who were not native signers (n = 19). We administered a battery of non-verbal reasoning, NVWM, and language tasks. We examined whether the groups differed on NVWM scores, and whether scores on language tasks predicted scores on NVWM tasks. For the two executive-loaded NVWM tasks included in our battery, the non-native signers performed less accurately than the native signer and hearing groups (who did not differ from one another). Multiple regression analysis revealed that scores on the vocabulary measure predicted scores on those two executive-loaded NVWM tasks (with age and non-verbal reasoning partialled out). Our results suggest that whatever the language modality—spoken or signed—rich language experience from birth, and the good language skills that result from this early age of acquisition, play a critical role in the development of NVWM and in performance on NVWM tasks.

Nonverbal Executive Function is Mediated by Language: A Study of Deaf and Hearing Children

Studies have suggested that language and executive function (EF) are strongly associated. Indeed, the two are difficult to separate, and it is particularly difficult to determine whether one skill is more dependent on the other. Deafness provides a unique opportunity to disentangle these skills because in this case, language difficulties have a sensory not cognitive basis. In this study, deaf (n = 108) and hearing (n = 125) children (age 8 years) were assessed on language and a wide range of nonverbal EF tasks. Deaf children performed significantly less well on EF tasks, even controlling for nonverbal intelligence and speed of processing. Language mediated EF skill, but the reverse pattern was not evident. Findings suggest that language is key to EF performance rather than vice versa.

Sentence Repetition in Deaf Children with Specific Language Impairment in British Sign Language.

Children with specific language impairment (SLI) perform poorly on sentence repetition tasks across different spoken languages, but until now, this methodology has not been investigated in children who have SLI in a signed language. Users of a natural sign language encode different sentence meanings through their choice of signs and by altering the sequence and inflections of these signs. Grammatical information is expressed through movement and configurational changes of the hands and face. The visual modality thus influences how grammatical morphology and syntax are instantiated. How would language impairment impact on the acquisition of these types of linguistic devices in child signers? We investigated sentence repetition skills in a group of 11 deaf children who display SLI in British Sign Language (BSL) and 11 deaf controls with no language impairment who were matched for age and years of BSL exposure. The SLI group was significantly less accurate on an overall accuracy score, and they repeated lexical items, overall sentence meaning, sign order, facial expressions, and verb morphological structures significantly less accurately than controls. This pattern of language deficits is consistent with the characterization of SLI in spoken languages even though expression is in a different modality. We conclude that explanations of SLI, and of poor sentence repetition by children with this disorder, must be able to account for both the spoken and signed modalities.

How do Typically Developing Deaf Children and Deaf Children with Autism Spectrum Disorder Use the Face When Comprehending Emotional Facial Expressions in British Sign Language

Facial expressions in sign language carry a variety of communicative features. While emotion can modulate a spoken utterance through changes in intonation, duration and intensity, in sign language specific facial expressions presented concurrently with a manual sign perform this function. When deaf adult signers cannot see facial features, their ability to judge emotion in a signed utterance is impaired (Reilly et al. in Sign Lang Stud 75:113–118, 1992). We examined the role of the face in the comprehension of emotion in sign language in a group of typically developing (TD) deaf children and in a group of deaf children with autism spectrum disorder (ASD). We replicated Reilly et al.’s (Sign Lang Stud 75:113–118, 1992) adult results in the TD deaf signing children, confirming the importance of the face in understanding emotion in sign language. The ASD group performed more poorly on the emotion recognition task than the TD children. The deaf children with ASD showed a deficit in emotion recognition during sign language processing analogous to the deficit in vocal emotion recognition that has been observed in hearing children with ASD.

Narrative skills in deaf children who use spoken English: Dissociations between macro and microstructural devices

Previous research has highlighted that deaf children acquiring spoken English have difficulties in narrative development relative to their hearing peers both in terms of macro-structure and with micro-structural devices. The majority of previous research focused on narrative tasks designed for hearing children that depend on good receptive language skills. The current study compared narratives of 6 to 11-year-old deaf children who use spoken English (N=59) with matched for age and non-verbal intelligence hearing peers. To examine the role of general language abilities, single word vocabulary was also assessed. Narratives were elicited by the retelling of a story presented non-verbally in video format. Results showed that deaf and hearing children had equivalent macro-structure skills, but the deaf group showed poorer performance on micro-structural components. Furthermore, the deaf group gave less detailed responses to inferencing probe questions indicating poorer understanding of the storys underlying message. For deaf children, micro-level devices most strongly correlated with the vocabulary measure. These findings suggest that deaf children, despite spoken language delays, are able to convey the main elements of content and structure in narrative but have greater difficulty in using grammatical devices more dependent on finer linguistic and pragmatic skills.

Detecting cognitive impairment and dementia in Deaf people: The British Sign Language Cognitive Screening Test

To provide accurate diagnostic screening of deaf people who use signed communication, cognitive tests must be devised in signed languages with normative deaf samples. This article describes the development of the first screening test for the detection of cognitive impairment and dementia in deaf signers. The British Sign Language Cognitive Screening Test uses standardized video administration to screen cognition using signed, rather than spoken or written, instructions and a large norm-referenced sample of 226 deaf older people. Percentiles are provided for clinical comparison. The tests showed good reliability, content validity, and correlation with age, intellectual ability, and education. Clinical discrimination was shown between the normative sample and 14 deaf patients with dementia. This innovative testing approach transforms the ability to detect dementia in deaf people, avoids the difficulties of using an interpreter, and enables culturally and linguistically sensitive assessment of deaf signers, with international potential for adaptation into other signed languages.

Working Memory and Deafness: Implications for Cognitive Development and Functioning

Publisher Summary Traditional conceptualizations of working memory (WM) make a number of well-founded assumptions about cognitive phenomena. Visuospatial and verbal processes are viewed as separable, and a sound-based phonological code is believed to underlie the processing of language. The construct of deafness can be framed in different ways. Both audiological and cultural definitions exist, but these can give rise to differing expectations. Given that the deaf experience differs dramatically from one child to another, many researchers argue strongly for an individual differences approach to study the development of deaf children. For centuries, sign languages have been fundamental to the communication of deaf people. The study of psycholinguistic phenomena has mainly focused on the mechanisms underpinning spoken language and modality-specific functions made possible by internal representations that reflect the phonological properties of speech. Standard memory assessment techniques are often not appropriate for use with children who are deaf. Because of the heterogeneity of the deaf population, it can even be inappropriate to compare two deaf children on the same test. Teaching methods should seek to tap into a deaf childs strengths. Educational approaches that rely heavily on verbal sequential coding are generally less appropriate for deaf children.