Assessing Deaf patients in the neurology clinic.

There are over 87 000 Deaf people in the UK with British Sign Language (BSL) as their first language.1 Few healthcare professionals receive training in Deaf awareness or in BSL, and missed diagnoses and inadequate treatment of Deaf patients are estimated to cost the National Health Service £30 million per year.2 Neurologists are likely to encounter Deaf BSL users in their practice, but without prior experience may find consultations challenging, especially within the time constraints and pressure of a standard clinic. In this article, we provide guidance on consulting with Deaf people in a neurology clinic, drawing on experience from our cognitive clinic for Deaf BSL users where effective communication is essential.

Evaluation of a specialist cognitive clinic for the Deaf community.

There are significant health inequalities between Deaf and hearing people, including barriers to accessing care and communication difficulties in consultations. Such problems have particularly affected Deaf people with acquired cognitive deficits, leading to late and missed diagnoses. We therefore established a specialist cognitive clinic for the Deaf community in 2011 at the National Hospital for Neurology and Neurosurgery, which to our knowledge is the first of its kind in the world. In this study, we retrospectively analysed electronic patient records to evaluate the service and its impact since inception. We found that Deaf patients who use British sign language had difficulty obtaining an accurate diagnosis before attending our specialist clinic, highlighting the importance of tailored services for Deaf people. Our results show that the clinic improved communication for patients and accessibility to specialist investigations, ensuring diagnostic accuracy and overall reducing health inequality for this population.

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.

The effects of cerebellar ataxia on sign language production: a case study.

Speech and sign production both require precise coordination of multiple articulators. The characteristics of dysarthria following ataxia have been well-documented, but less is known about the consequences of ataxia for sign language, which uses the hands and arms as articulators. This is the first study to examine ataxic dysarthria in a sign language user. What is novel in this research is that the limbs are employed for both linguistic and non-linguistic movements. Notably, sign production deficits broadly resembled ataxic dysarthria, while non-linguistic movement deficits were similar to those previously reported for ataxic limb movement.

The perceptual characteristics of voice-hallucinations in deaf people: insights into the nature of subvocal thought and sensory feedback loops.

The study of voice-hallucinations in deaf individuals, who exploit the visuomotor rather than auditory modality for communication, provides rare insight into the relationship between sensory experience and how "voices" are perceived. Relatively little is known about the perceptual characteristics of voice-hallucinations in congenitally deaf people who use lip-reading or sign language as their preferred means of communication. The existing literature on hallucinations in deaf people is reviewed, alongside consideration of how such phenomena may fit into explanatory subvocal articulation hypotheses proposed for auditory verbal hallucinations in hearing people. It is suggested that a failure in subvocal articulation processes may account for voice-hallucinations in both hearing and deaf people but that the distinct way in which hallucinations are experienced may be due to differences in a sensory feedback component, which is influenced by both auditory deprivation and language modality. This article highlights how the study of deaf people may inform wider understanding of auditory verbal hallucinations and subvocal processes generally.

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.