The level of hearing impairment opens various prospects (continued…)
“… The second group of moderate hearing loss (50 to 70 dB), is fully compatible with a social life, provided that the hearing loss was diagnosed at an early stage, that the patient was equipped with appropriate hearing aids and benefits from a proper education, regular medical supervision and speech therapy, and a thorough social and educational monitoring. There can be no ordinary social behaviour without a proper equipment with hearing aids. Those children should not be considered as disabled, and the particular methods employed for severely death patients should not be applied to them. If no other disabilities are detected, those children should benefit from a regular curriculum and attend the same teaching as other children; the family environment is the only suitable one here, unless serious issues are encountered – issues that may also be experienced with hearing children. In case of behavioural disorders, these originate from educational blunders and only require complementary psychotherapy that will also, and very importantly, provide guidance to the parents. These therapy sessions do not have to be attended too frequently, and can thus be attended by any family – at least in France. A psychiatric assessment may help in the diagnosis of a potential mental disorder associated with hearing impairment. However, in most cases, the disorder originates from relationship difficulties linked to the hearing loss. In case of a true mental disorder, which has to be established, it will be deeply affected by a hearing loss of moderate level. This is more easily understood in case of severe and, even more so, in case of profound hearing loss.
As for severe hearing loss (between 70 and 90 dB), hearing aids are mandatory for speech elaboration during the educational process. The compensation brought by hearing devices allows speech development under monitoring through a thorough speech therapy. Most of the time, these children benefit from a regular curriculum – provided that they were diagnosed at an early stage and monitored properly, and when education and speech therapy were adapted accordingly. A higher level of care is only required under specific social circumstances, or in presence of an associated disability or in case of severe educational blunders. The proposed orientation is a probability. It depends on the child’s adaptation to communication. As many severely deaf patients as possible should be able to benefit from a professional training identical to that attended by hearing people.
As for profound hearing loss, the residual hearing in the high-pitched frequencies range results in a completely different prognosis for perception, i.e. if some hearing capacities remain under a 100 dB loss threshold, or if nothing at all can be heard in the high-pitched range. And this, no matter the group they belong to, although, in principle, these would be part of the first group. But why is that? Simply because people who are properly equipped with powerful hearing aids with a wide bandwidth are able to hear in the 1,000, 2,000 and 4,000 octave bands involved in the transmission of the vocal timbre. Indeed, these octave bands include almost all of the relevant characteristics of the phonetic structures of speech that can be identified. This type of profound hearing loss can be adapted to verbal, acoustic messages of high intensity. This is not the case for profound hearing loss of groups 2 and 3, where only a very few acoustic signals are usable. These mainly consist in information about complex ensembles of speech, about the main characteristics of tunes and sentence rhythms. However, it is crucial to assess the potential evolutivity of deafness. Indeed, an adult suffering from profound hearing loss may have only suffered from severe hearing impairment in childhood, and is thus not affected by the disability one would expect to see in profoundly deaf people. When considering the social situation and the relationship to the outer world of a deaf patient, one should always keep in mind the onset time and the evolution of deafness, how much and how quickly it aggravated over time.
In the third group of profound deafness, when residual hearing is at 250 Hz and 500 Hz for a threshold of hearing loss beyond 110 dB, or even when no residual audition can be detected at all, this phenomenon is called cophosis. These cases of complete deafness are extremely rare: these are either cases of acquired deafness (meningitis or fracture of the petrous part of the temporal bone), or result from the evolution of a profound hearing loss. The perception of the surroundings and the psychological structuration acquired beforehand obviously depend on the onset time of deafness and on how quickly it evolved during childhood. The hearing provides no information about the external world” (1).
(1) Prof. J.C. LAFON « les enfants déficients auditifs » (« hearing-impaired children ») pp. 108-109.