Tanya Denmark

The British Sign Language (BSL) norms for age of acquisition, familiarity, and iconicity.

Research on signed languages offers the opportunity to address many important questions about language that it may not be possible to address via studies of spoken languages alone. Many such studies, however, are inherently limited, because there exist hardly any norms for lexical variables that have appeared to play important roles in spoken language processing. Here, we present a set of norms for age of acquisition, familiarity, and iconicity for 300 British Sign Language (BSL) signs, as rated by deaf signers, in the hope that they may prove useful to other researchers studying BSL and other signed languages. These norms may be downloaded from www.psychonomic.org/archive.

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.

Investigating the underlying causes of SLI: A non-sign repetition test in British Sign Language

There is controversy over the specificity of Specific Language Impairment (SLI), and whether it is caused by a deficit general to cognition or in mechanisms specific to language itself. We argue that evidence to resolve these conflicting positions could come from the study of children who are acquiring sign language and have SLI. Whereas speech is characterized by rapid temporal changes, the phonology of sign languages relies on the integration of visual information that is often produced simultaneously. These differences in the way linguistic information is processed can allow us to investigate whether SLI is caused by a sensory processing deficit, by a deficit specific to language, or by a deficit in phonological short term memory. One marker for SLI in spoken languages is difficulty repeating non-words, particularly those with complex phonological structures. We report on the development of a non-sign repetition task for BSL users, piloted on deaf children, which is sensitive to age. Non-sign items were graded in terms of phonological complexity, and reveal systematic error patterns as a function of that complexity. We conclude by discussing how this test can be used to probe the underlying nature of language impairments.

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.

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.

Signing with the Face: Emotional Expression in Narrative Production in Deaf Children with Autism Spectrum Disorder

This study examined facial expressions produced during a British Sign Language (BSL) narrative task (Herman et al., International Journal of Language and Communication Disorders 49(3):343–353, 2014) by typically developing deaf children and deaf children with autism spectrum disorder. The children produced BSL versions of a video story in which two children are seen to enact a language-free scenario where one tricks the other. This task encourages elicitation of facial acts signalling intention and emotion, since the protagonists showed a range of such expressions during the events portrayed. Results showed that typically developing deaf children produced facial expressions which closely aligned with native adult signers’ BSL narrative versions of the task. Children with ASD produced fewer targeted expressions and showed qualitative differences in the facial actions that they produced.

Identifying dementia in deaf sign language users

DCAL, University College London, 49 Gordon Square, London WC1H 0PD, UK Email: t.denmark@ucl.ac.uk SORD, Jean McFarlane Building, University of Manchester, Oxford Road, Manchester M13 9PL, UK Email: dwd@manchester.ac.uk This work is funded by the Alzheimer’s Society Background Tests used to identify dementia in users of spoken languages are unsuitable for Deaf people who use sign languages. British Sign Language (BSL) is unrelated to spoken English. Linguistic, cultural and educational differences mean that using interpreters or written English formats is unreliable and error prone, particularly as communication itself is part of the assessment. Diagnosis of deaf patients is typically late with adverse consequences for access to medication, rehabilitation and care planning. Establishing the norms of healthy ageing in the Deaf sign language community in respect of cognitive and linguistic functioning is a necessary precursor to the development of assessment tools that might be used to detect unusual changes associated with dementia. Here we present the first BSL cognitive screening test, akin to the widely used cognitive screens in the UK such as the Mini Mental State Examination and Addenbrookes Cognitive Examination (ACE-r, Mioshi, Dawson et al. 2006). We have begun using this test as part of routine clinical practice with Deaf patients at the National Hospital for Neurology and Neurosurgery in England.