Characteristics of Children With
Specific Language Impairment
University of Manchester
The identification and classification of a clinical population such as children with specific language impairment (SLI) is universally recognized as a continuing challenge for clinicians and researchers alike (Bishop, 1997; Leonard, 1998). SLI is not a homogeneous disorder, but a term currently used to describe children with a range of profiles, all of which include marked language difficulties in the context of normal cognitive abilities. It represents a pattern of impairment where no other identifiable cause for communication difficulties is present. Thus, SLI works on an exclusionary basis, in which children with autism, general learning disability, physical or neurological damage (such as cleft palate, cerebral palsy, or head injury) are not included in the categorization. Despite that SLI has been studied and treated in some form or another for over 100 years, positive definitions have been hard to agree on (Aram, 1991; Bishop, 1994; Johnston, 1991; Leonard, 1987, 1991). This is due in part to the wide spectrum of different impairments often made up of combinations of deficits in particular areas of communication (phonology, morphology, syntax, semantics, pragmatics). The profiles of children with SLI are also dynamic over time. That is, children who are identified as having a certain pattern of difficulties may improve in some areas and not in others, giving a different profile from year to year.
In England, since the 1960s, the education system has allowed special status to children with SLI who have persistent problems. A wide range of models of intervention is current, from full-time special school placement