Catégorie : Capacités cognitives

The past 23 articles detailed what HEARING and LANGUAGE were, individually.

But what makes the link between the HEARING and the LANGUAGE?

According to Prof. J.C. LAFON, several functions are required to make the transition from hearing to language:

1) The ACOUSTIC FUNCTION.

2) The INTEGRATIVE FUNCTION.

3) The LANGUAGE FUNCTION.

4) Other functions that are part of the INTEGRATIVE FUNCTION.

5) The SEQUENTIAL FORMS OF KNOWLEDGE.

“Acoustic messages received by the cochlea are processed and integrated in the nervous system, they are compared to previously acquired symbols and identified as significant elements. This function is complex and corresponds to both the hearing and the understanding…”(1).

1) The ACOUSTIC FUNCTION.

“The acoustic function relies on the combined functioning of the middle ear and the cochlea; it is part of the scope of physiological activity studies. The transmitted sounds result in acoustic vibrations that trigger a complex motion of the basilar membrane based on the cochlear resonance, that we call the “cochlea-dependent motion”. Impairment of the basilar membrane’s motion is a cause of deafness clinically identified by a rise in the sounds perception threshold.”(2)

The scope of the acoustic function ends at the organ of Corti level.

2) The INTEGRATIVE FUNCTION.

“The integrative function sets up the link between the cochlea-dependent motion of the basilar membrane and the language. It consists in two main activities: the first one, of neuro-physiological nature, concerns the auditory pathways and centres ; it can be studied by electrophysiology. The second activity, of psycho-physiological nature, relies on memory circuits and thus, on multiple synaptic associations; it is based on psychological capacities. It can be studied, on the one hand by physiological measurements, and on the other hand, by psychological observations. It is when facts are translated into abstract notions, and images into symbols. Impairment of this function results in auditory agnosia in adults, and, in children, it causes either an integration impairment or a delayed integration depending on whether it is due to a dysfunction of the auditory pathways or due to a multifunction of the memory circuits; the latter can be improved, as they can be partially compensated.” (2)

The three other functions will be discussed in the next two articles.

JYM

(1) Professor J.C. LAFON « message et phonétique » (« message and phonetics ») pp. 67-68

(2) Professor J.C. LAFON « message et phonétique » (« message and phonetics ») page 68.

(3) Professor J.C. LAFON « message et phonétique » (« message and phonetics ») pp. 68-69

« La descubierta del mundo exterior por el niño y la construcción de su relación con el mundo exterior constituyen progresivamente lo que se llama su lenguaje. » (1).

« El lenguaje es algo interiorizado, y la palabra es su expresión. » (2)

« El lenguaje es la forma de los movimientos del alma. No solo los figura: los provoca, los determina, los orienta, los eleva a la conciencia. Constituye el espíritu. » (3).

« El alma – vocablo tan necesario, aunque evasivo al igual que su objeto – en primer lugar es este principio de individualización supuestamente distinto al cuerpo donde brota, penetrándolo y formando un solo ser con este durante la vida. Mi alma, es mi campo de fuerzas, mi naturaleza, mi ser en su única inmanencia, la única substancia y el halo psíquico de mis yo plurales (a la diferencia – relativa y no absoluta – de mi espíritu que es mi ser en movimiento hacia el Ser, por lo tanto despierto a la trascendencia del Ser en el). » (4).

«…el alma es lo que nos permite desear, sentir, emocionarse, resonar, conservar memoria por todas partes, hasta enterrada, hasta inconsciente de nuestro vivido y, sobre todo, conectarse por afecto o por amor… El espíritu es lo que nos permite pensar, razonar, concebir, organizar, realizar, acumular conscientemente las experiencias para aprender y, sobre todo, comunicar por intercambio. Explotando los recursos fónicos del francés, tuve la oportunidad de proponer fórmulas que se querían « contundentes », como: « El espíritu razona, el alma resuena », « El espíritu se mueve, el alma se conmueve », « El espíritu es comunicación, el alma es comunión », « El espíritu yang ‘masculino’, el alma yin ‘femenino’ « Estas fórmulas, que tal vez son demasiado simplificadoras, tienen el mérito de mostrarnos el lazo íntimo que une los dos, al mismo tiempo de destacar lo específico de cada uno. » (5)

JYM

(1) Pr J.C. LAFON « Echantillonnage de textes » página 17.

(2) Pr J.C. LAFON « El niño sordo antes de los 3 años » Desafíos y obstáculos de la educación temprana, actos del simposio internacional organizado por la A.N.P.E.D.A. París 2, 3 y 4 de noviembre de 1979 página 145.

(3) Pierre EMMANUEL de la Academia francesa (sillón 4), fallecido en 1984, « Le goût de l’Un » página 173.

(4) Pierre EMMANUEL de la Academia francesa (sillón 4), fallecido en 1984, « Le goût de l’Un » página 16.

(5) François CHENG de la Academia francesa (sillón 34), « De l’âme » página 40-41.

To quote Prof. J.C. LAFON:


« The level of hearing impairment opens various prospects.


Naturally, the hearing threshold is only one of the characteristics that allow sounds to be perceived by human beings based on their spectral composition. In other words, that information only tells us there may be a signal, but by no means whether that signal is perceived properly, if it is identified properly, and all the less so if it is useful in understanding the global message. Actually, those levels, calculated and expressed in decibels, provide information on what cannot be perceived: they provide adverse data.


It is generally acknowledged that hearing devices only become necessary for patients to perceive their surroundings when the general impairment reaches a level of 35 dB of hearing loss, and a level of over 30 dB of hearing loss in the 2000 Hz octave band. And vice versa: hearing aids are considered to be properly fitted and to provide a reliable improvement when maximal acoustic capacities display a hearing loss of about 30dB, as opposed to normal hearing. Basically, an average level of hearing loss inferior to 40 dB is enough to maintain a perception of the surrounding environement: of course, some useful information will be altered, but to a degree that is sufficient to maintain the capacity to create a coherent mental representation, compatible with a normal social life.


And this is all the more so because the ambient backgroung noise often reaches those levels in daily life: it has a similar effect to an increase in hearing threshold. The onset of acoustics events during the hearing process does not display major variations compared to a normal hearing function. Indeed, the main relevant characteristics of speaking out loud – the average level of which is 60-70 dB HL at proximity to the speaker lips – can be perceived… and a bit of lip reading provides the complementary information. This explains why, nowadays, we still come accross teenagers suffering from a light sensoneurinal hearing loss that is only diagnosed when they get to university, and that remained undetected till then (such cases occur less often than in the past, though, due to a systematic control of hearing function at earlier stages). However, the impairment does exist and results in an incapacity to hear whispering voices, remote sounds or rustles: all of this does cause some inconvenience in social life and restrain the environment. The combination of an additional impairment in the child will have major consequences: the amblyopic patient will lack the complementary information for a proper hearing, a patient with mental disease will suffer from a stronger sensoneurinal impairment, disabled people will have more trouble to structure their environmemnt, etc. It is thus crucial to check the hearing function in all patients suffering from sensory, intellectual or physical disabilities, and to treat any hearing impairment no matter how light it is.


The next level of hearing loss is set at 50 dB, the average level of hearing disabilities. As a result, we distinguish an up-to-50 dB group and a beyond-50 dB group of average hearing impairment. This is the point where most of the acoustic information contained in speech is not accessible to the hearing impaired. Below that average threshold, and in particular if the test shows a better hearing of deep or high-pitched sounds, the relevant sounds that are perceived allow an autoadjustment of the patient’s voice. Indeed, those patients can control their voice, tune, pace, vocal timbre and phonatory production. Above the 50 dB level of hearing loss, some timbres are missed. An absence of high-pitched tones alters the quality of the voice, as if it was timbre-depleted, the movements of the soft palate cannot be controlled properly and the articulation of consonants – those with a high-pitched tone in particular – is not as sharp as normal, it is diminished by as much as what the patient can hear. This 50 dB threshold of average hearing loss will be addressed at a later stage, when the disabling aspects of hearing impairment will be discussed. This is when we get to the world of deafness as the society conceptualises it: the verbal and social impairment, the impact on schooling, the attitude of the hearing impaired…»(1).


JYM


(1) Prof. J.C. LAFON « les enfants déficients auditifs »(« hearing-impaired children ») page 107.