The auditory system, as in all other sensory modalities, requires the normative input of sound stimulation provided that the anatomical-functional development of the system is carried out correctly. The auditory system is made up of three sets of structures.

Therefore, it is important to prevent possible language development problems in children with hearing impairments , since this vital stage is key in the formation of the cognitive processes that interact with the use of abstract concepts and words. In this article we will review several keys to be taken into account in this regard.

Language development in children with hearing impairment

In the presence of a significant hearing impairment during childhood, the linguistic ability can be affected in a very variable way depending on the area most affected, and it is possible to differentiate between vocabulary, grammar, articulation, fluency, comprehension, pronunciation, etc.

In addition to the type of impairment the child has, language development is also influenced by the nature and quality of the communicative environment around the child, so that greater language ability seems to be achieved if the mother is hearing with respect to the case where both mother and child are deaf.

More specifically, with regard to how the linguistic development of the deaf child takes place , it can be seen that, during the first 9 months, these babies show a level of vocalization similar to that of non-deaf children. At that time, discrepancies are observed in the quantity and quality of the little ones’ oral productions. This is due to the fact that the baby does not receive enough environmental reinforcements to encourage him/her to perform such verbalizations.

Generally speaking, it can be said that the development of a deaf child in relation to a child who is not deaf follows the same phases in both cases, although in the case of a deaf child it occurs more slowly. In the area of syntax many difficulties are observed , to the point that they do not manage to master the complex structures even at the age of 18 (a milestone which does occur in hearing children at the age of 8). Thus, the content of the broadcasts is simpler, with less significant content in plurals, prepositions, conjunctions or pronouns, as well as alterations in elements of the sentence such as plurals, verb tenses or gender.

Pronunciation is strongly altered in relation to intonation, rhythm, tempo, etc., as well as other serious syntactic distortions. As regards comprehension, the child must use visual cues to help him understand the stimulation received. They also use lip-facial reading and other complementary methods that facilitate the differentiation between lip movements shared by different phonemes or phonemes that do not have visible lip movements.

Differences in morphosyntactic development

Research that has tried to study the differences that occur between the morphosyntactic development of a hearing child and a deaf child shows that the latter presents both deviations and delays in learning grammar and morphosyntax, in particular.

In more detail, studies have found that the length of sentences is significantly shorter in 17-year-old deaf children than in 8-year-old hearing children. Related to this, it has been found that deaf children do not elaborate complex sentences, unlike hearing children of 11 years old, who begin to master this ability.

Furthermore, the sentence constructions of hearing-impaired children are not very syntactically varied and the use of adjectives, auxiliaries and conjunctions is observed to a lesser extent in contrast to the greater use of nouns and verbs (which can be attributed more meaning, making evocation of the concept they represent more accessible), articles, pronouns and prepositions are also scarce in non-listening children. Thus, the greatest differences between one group and another refer to the use of words “function”.

Another group of research has found three main findings in the comparison between hearing and deaf children: for the latter it is much more complex the application of structures that include pronouns, the conjugation of the verbs and the formation of long sentences ; the deaf do not reach a complete development of the language at the age of 18 although the evolution of the learning of the language is progressively positive for simple sentences (not so in the complex ones); the greater number of errors is concentrated in the use of words function in the group of the non hearing ones.

Finally, at the neurophysiological level, other studies aim to analyze the level of specialization in the left hemisphere through the activity recorded by evoked potentials after the presentation of certain word lists.

The result obtained shows a discrepancy in the brain area activated during this task between the hearing and the deaf: the anterior left brain areas were activated by the word function, while the posterior parietal areas, in both the right and left hemispheres, were activated for the words with semantic content. Thus, it can be concluded that the ability of morphosyntactic domain depends on the modality in which the linguistic stimulation received is produced.

Guidance on optimizing oral language learning

Silvestre (1998) has proposed a list of conditions considered optimal for the learning of the oral language .

1. Family involvement

A high frequency of parent-child exchanges is recommended to enhance the stimulation received by the child, ensuring a higher level of progress.

2. Early educational care

With the aim of reaching the highest possible degree of development taking into account the sensitive periods of myelinization and neuronal plasticity.

3. Correct fitting of the hearing aid

Essential for a correct interaction between the child and the environment.

4. Early hearing retraining

Essential to compensate as far as possible for the deficiencies presented in each specific case.

5. Acquisition of lip-facial reading

It becomes a requirement for the understanding of the oral language received by the speaker present.

6. Communicative and cognitive development

Since there is a close relationship between organic and psychological development, action must be taken to prevent difficulties in the former (hearing impairment) from leading to damage in the latter (psychopathology or emotional or cognitive distress).

Bibliographic references:

  • Marchesi, A. (1987). Cognitive and linguistic development of deaf children. Madrid: Alianza editorial.
  • Peña , J. (1992). Manual de logopedia (3a ed.). Barcelona: Masson.
  • Puyuelo, M., RONDAL, J., WIIG, E. (2002) Evaluation of language.1a reprint. Barcelona: Masson.
  • Puyelo, M. (2004) “Manual del desarrollo de la deafera” Barcelona. Masson.
  • Silvestre, N. (1998) Deafness, communication and learning. Barcelona. Masson.