Linguistic treatment of relative clauses in an adult deaf LIS signer: A case study

In this study it will be investigated if it is possible to enhance the comprehension and production of relative clauses in an adult deaf LIS (Italian Sign Language) signer through a period of linguistic treatment. Some studies showed that linguistic rehabilitation gave positive results with aphasic adults (Thompson & Shapiro 1994), with hearing-impaired children fitted with cochlear implant (D’Ortenzio 2014), and with SLI adolescents (Levy & Friedmann 2009) and children (Ebbels & van der Lely 2001). The aims of this study are to verify if this kind of treatment can be effective also for an Italian deaf adult signer of LIS, if the potential positive effects are maintained for some time after the syntactic treatment, and if improvements occur also in passive clauses. The data analysis revealed an asymmetry between production and comprehension of relative clauses after the linguistic treatment session, where a considerable improvement had been detected mainly in production. These results suggest that syntactic structures can be rehabilitated, at least partially, even in adult subjects, but the unusual asymmetry between comprehension and production (having the latter improved more than the former) still has to be clarified. The performance on passives comprehension did not changed before and after treating relative clauses, while findings from production will be discussed. To date this is the first attempt to rehabilitate relative clauses lead on a deaf adult subject.