4. Atypical Language - Results
This strand has investigated how a range of linguistic and cognitive impairments impinge on the acquisition and breakdown of signing. This included developmental disorders of sign language; autism and sign language; acquired impairments in sign language, including the effects of brain lesions on sign language processing; sign language processing when sight fails (Usher’s syndrome) and neuropsychiatric disturbances in sign language including schizophrenia. The Deaf Children with Specific Language Impairment (SLI) project had outstanding success in recruitment, receiving over 60 referrals from schools. We tested this group on language and cognitive measures. The results showed convincingly that characteristic SLI profiles can be found in Deaf children who use BSL as a first language. This challenges current ‘auditory’ based theories of SLI and provides valuable practical information for professionals working with Deaf children with language learning problems. The results were presented at several international conferences including a symposium at the Society for Research in Child Development in April 2009. We published the first set of studies for this project for a special issue of the British Journal of Developmental Psychology (Mason et al 2010; Marshall, et al 2012). Work in the same strand was awarded a Leverhulme 3 year (2008-2011) post-doctoral fellowship for Dr Chloe Marshall (based at City University with Morgan).
In the study of deaf children with autism PhD student Tanya Denmark has investigated face processing in typically-developing deaf children and deaf children and adults with autism. Results indicate that counter to predictions, signers with autistic spectrum disorder (ASD) are able to process facial information relating to sign language, suggesting that linguistic information on the face may be processed by a different route than social and affective facial expressions.
In the work on strokes in deaf signers we have carried out in-depth analysis of group data on sign language production in left and right damaged signers, hand dominance in signing and fingerspelling, and case studies of ataxia in sign language following cerebellar stroke (Tyrone et al, 2009) sign palilalia in progressive supranuclear palsy (Tyrone & Woll, 2010) and BSL learning by a linguistic savant (Smith et al., 2010).
The work on Usher syndrome (deaf-blind signers) centres around several experimental studies: a functional imaging study of tactile vs. visually perceived fingerspelling (Capek et al, in preparation); an instrumented measurement study of the production of spatialised grammatical relations (Arena, Finlay & Woll, 2007), and a linguistic study of production and perception of spatialised grammatical relations (Morgan et al, 2009; Woll et al, 2009).
Research into voice hallucinations in signers with schizophrenia also produced new insights into the nature of the feedback loop for sign language (Atkinson, 2007).
Researchers: Professor Jane Marshall, Dr. Joanna Atkinson, Dr Cheryl Capek, Dr Tanya Denmark, Dr Martha Tyrone, Valentina Arena, Kathryn Mason, Kathryn Rowley, Sarah Reed, Ramas Rentelis, Sharita Sharma.