ORAL LANGUAGE ACQUISITION IN CHILDREN WITH DOWN SYNDROME
Down syndrome (DS) is an irreversible congenital disorder caused, in most cases, by the trisomy in the chromosome 21 due to the non-disjunction during the meiosis.
The incidence in Mexico of DS is approximately of 1 out of each 800 births per year. The otorhinolaryngologic morbidity in the DS is well-known; however, its repercussion in the linguistic development of these patients has not been estimated yet.
The present study aims to evaluate the relevance of the hearing anatomy and physiology that appear in DS patients and its impact in their oral language acquisition. We analysed eight patients diagnosed with Down syndrome with ages ranging between 2 and 14 years old, who were monitorised using conventional methodology of speech therapy.
Their hearing examination included an otoscopy of the morphology of the ear canal and the eardrum, as well as functional tests of the middle ear, the inner ear and the auditory nerve fibres (pure tone audiometry, speech audiometry and brainstem auditory evoked potentials).
More than half of these children came from a Mexican area with an underprivileged socioeconomic status, so they were not able to adequately access to the services and care that a minor with DS should receive. This circumstance contributed to an important retardation in learning, acquisition and development of language and communication, which turned out to be comparatively greater than the one typically registered for DS. Most of them did not receive early therapeutic care; instead, usual therapies were applied to them when they were already 2 years old or older.
Although there were morphological differences in the configuration of the typical outer ear of DS patients, they did not seem to be a conditioning factor of the hearing ability of these patients. In most cases, the results of the functional hearing tests were within normal ranges, with the exception of 1 case.
As a result we can say that, considering the cases with DS that have been studied, and aside from factors such as an adequate morphology and hearing function, adverse socioeconomic factors have a negative repercussion in oral language acquisition in the early years of life.