LANGUAGE SYSTEMS AND PLASTICITY  (developed by Veronique Bure)

Language is only one component of communication and is thought to have developed late in the human evolution, emerging approximately 30000 years ago. It is a powerful tool  built through meaningful interactions with caregivers through early childhood . which in turn allows to access more  complex social interactions. Language is more than speech and implies a neural organization underlying the complex functions it encompasses. Speech is the capacity of one individual to alter, through sounds emission, the mental organization of another individual in order to bring this individual to a stage of mind close to his own.

All languages have semantics ( meaning) and grammar but they vary considerably.  Oral languages present an amazing range of organization and possibilities. These variations are demonstrated across languages such as Chinese, spoken with variants by one fifth of the world population, which is a monosyllabic (words are made of one syllable)  language using tones/pitch  to express different meanings of words; Eskimo language (spoken by very few) in which a sentence can consist of a single word with up to 8 suffixes, infixes and prefixes and the Natal Colony ( South Africa) set of languages  among which the Hottentots' is the most surprising for an occidental ear.  Most words in the Hottentots' dialects begin with a click like sound.  Clicks are of four kinds and pretty difficult to describe to those who have not heard them (similar to sounds made in the drawing of a cork, the gurgling of water in the neck of as bottle, the tclah used in making a horse trot..).  All spoken languages require specific sound and articulation skills as well as different ways to organize sensory information and complex thinking.  Each language is structured around emphasis on different concepts, (time-conjugation, order-syntax, gender, tones –semantics, emphasis on actions through verbs, on identities with nouns…).  In spite of these variations, infants of all culture seem to achieve milestones for language mastery in a similar time frame.  Petitto and Marentette (1991) published a paper demonstrating that deaf children exposed to sign language "babble" with their hands, producing  systematic actions, that are not observed in hearing children.  This form of manual babbling occurs around 10 months of age, the point at which vocal babbling occurs in hearing children.

Evidence of brain plasticity

The neural systems involved in language show an extraordinary degree of plasticity. Research on the long term effect of early focal brain injury suggests  that most children with large lesions to the classic language zones  manage to reach levels of language ability that have very little or no discrepancy from typical children’ s (Bates et al., 1992.).   However, regardless of the side, size, or site of lesions, most children with brain injury are delayed in the first stage of language production. The fact that the deaf communities have developed  elaborate linguistic systems in the visual  manual modality demonstrates the brain and the behaviour plasticity of human beings.  These two components allow building alternative systems to achieve communication when the initial and specific one is damaged. The recovery of language observed in children with brain injury represents a true re-organization leading to an alternative to the impaired structure.  It is  as if experience can re-sculpt the brain.

Delayed language use in children with ASD

The amazing plasticity  of the brain is not enough to counterbalance the severe  communication impairment displayed by children with Autism.  Their difficulty in acquiring words, the peculiar use of pronouns and of syntax, the lack of use of other communication strategies to compensate the delay in language ( non verbal communication) reflects a more global social emotional impairment.  It seems as if in a child with Autism the different systems of the brain do not cooperate and coordinate their functioning.  This type of collaboration in critical to achieve language mastery and  complex thinking on which depend the capacity to interact socially. (See emotion based language stages).

Early intervention for children with Autism is therefore critical in order to build up alternative systems , behaviourally and neurologically. The acquisition of an expressive and receptive language is a good predictor of social emotional and cognitive growth.   Children with Autism should intensely be exposed to monitored social  interactions and language. These complex behaviours must be explicitly fragmented into small steps and practiced. Children with Autism might be highly skilled in specific domain but are unable to utilize these skills  toward  compensating for their deficits.