Linguistic Comparison Between Language Development of People With Down Syndrome and People With Developmental Language Disorder

Abstract

Down syndrome, a genetic neurodevelopmental disorder, is caused by a chromosomal abnormality and is accompanied by mild to severe intellectual disabilities. From the beginning of people with Down Syndrome's lives, they face learning difficulties, mainly in the areas of grammar, articulation, and syntax with a delay in both non-verbal and verbal communication. Developmental language disorder, the causes of which have not yet been elucidated, consists of the failure to develop language and age-expected language skills in an otherwise typically developing individual. It is noticed in the early developmental period of the person and affects, as in Down syndrome, the quality of life of the person as a whole, as one or more language areas are affected. The purpose of this paper is to describe the language deficits of the above two disorders, to join the different levels of linguistic analysis, to describe the ways of manifestation and the criticality of the deficits, and to evaluate them in terms of their severity for the quality of life of these individuals.