LANGUAGE ORIGINS SOCIETY UNIVERSITY OF CAMBRIDGE Selwyn College September 1992 Robin Allott AUTISM AND THE MOTOR THEORY OF LANGUAGE.

LANGUAGE ORIGINS SOCIETY

UNIVERSITY OF CAMBRIDGE Selwyn College

September 1992

Robin Allott

http://www.percepp.com

AUTISM AND THE MOTOR THEORY OF LANGUAGE

ABSTRACT

Autism is a puzzling and distressing state which affects a considerable number of children world-wide. Autistic children display a range of deficiencies and often present bizarre patterns of behaviour. There is no consensus about the causes or treatment of autism. There may be a genetic element and autism may be a manifestation of errors in the programming of neural development pre- and post-natally.

One of the central and most discussed aspects of autism is deficiencies in speech development; absence or distortion of the use of words and of syntax make communication difficult for autistic children. Coupled with their notable lack of social empathy, this intensifies the isolation from which the children suffer. No clearly successful treatment for their language or other difficulties has as yet emerged. Given this, it seems desirable to examine whether the different ideas about the origin and functioning of language offered by the motor theory may be relevant in understanding the nature of autism or suggesting ways in which these unfortunate children might be helped, in tackling their language deficiencies or more widely.

What is autism?

The short answer is : no one really knows but there have been many excellent accounts of manifestations of autism in children by experts such as Lorna Wing, Frances Tustin, Uta Frith, Patricia Howlin and many others. The following account draws directly upon their descriptions of autism and upon the summary of the features of autism by the National Autistic Society. Autism is a disorder affecting cognition and language development. They have problems in understanding and using any form of communication, non-verbal as well as verbal. Some autistic children do not develop any useful language at all or else use only stereotyped words or phrases that have little or no meaning.

There are also cognitive difficulties. Although they can remember experiences, autistic children seem unable to imbue them with significance beyond the immediate, literal meaning, or to classify such events so that they fit into a gradually developing, coherent mental picture of the world. There is a strange combination of marked abnormality and yet relatively intact abilities together with normal physiognomy and an apparently intelligent expression. The highly unusual patterning of skills and deficits has given rise to the notion that, somehow, if only the right key could be found, the solution to all the child's handicaps could be discovered but no such key has been found.

The autistic child has no sense of 'me' and 'not-me' except in fleeting moments of awareness. Such a child lives mostly in terms of the outlines of shapes. Touch seems to be the predominant mode of experience and seeing, hearing and even smelling are felt to be tactile experiences. People are treated as things which are extensions of the child's own bodily 'things'. The handicap is in its nature more similar to blindness or deafness than to, say, shyness. Autistic children have an obsessive desire for sameness.

The autistic child has no sense of 'me' and 'not-me' except in fleeting moments of awareness. Such a child lives mostly in terms of the outlines of shapes. Touch seems to be the predominant mode of experience and seeing, hearing and even smelling are felt to be tactile experiences. People are treated as things which are extensions of the child's own bodily 'things'. The handicap is in its nature more similar to blindness or deafness than to, say, shyness. Autistic children have an obsessive desire for sameness.

Perhaps more difficult to explain are the unusual responses to sensory stimuli. Oversensitivity to certain sounds, fascination with bright lights or objects that spin, and indifference to pain, heat or cold may all occur in young autistic children. The way these children cover their ears to shut out or modify sound is often remarked upon. Often there are paradoxical responses to sensations (e.g. covering eyes in response to a sound, or ears in response to a visual stimulus). Play is ritualistic and lacking in imagination, most noticeably in those autistic children with the most severe language impairments.

Autistic children are incapable of understanding emotion in others. All autistic children suffer a severe lack of empathy - the ability to put themselves in the place of another person. They are indifferent to others' distress. They seem to lack the normal child's awareness of other human beings.

Who are the autistic children?

It has been calculated that there are approaching 5000 autistic children in England and Wales, slightly more than the number of blind and partially sighted children and slightly less than the number of deaf children. The sex ratio, male to female, increases with increased ability. At the lowest levels, the ratio is 2 : 1. At the highest ability levels the ratio rises remarkably to 15 : 1. About three fifths of autistic individuals remain severely handicapped, with only about one in six likely to make a sufficiently good social adjustment to live independently. These 'shell-type children' are as alike as peas in a pod both in their appearance, the kind of parents they have and their early developmental history (Tustin, 1980: 28), remarkably similar even if they come from different countries and communities. Often they belong to families of superior socio-economic status

Besides descriptions of autistic children by psychologists and other professionals, there have been some accounts of the autistic experience by parents and by the sufferers themselves. One at age 31 recorded his recollection of autistic childhood as continual confusion and terror; everything was unpredictable and strange. A very recent account by someone who eventually was diagnosed as autistic, and later, remarkably, took a degree in psychology while still remaining autistic, shows close agreement with the general picture of autistic children's behaviour and experience.

A few extracts: When people didn't touch me I never experienced this as neglect. I experienced it as respect and understanding. Love and kindness, affection and sympathy were my greatest fears. Staring into space ... spinning ... A means of losing awareness of self...Hurting oneself ... To test as to whether one is actually real. Head banging To fight tension and provide a thudding rhythm in my head when my mind was screaming too loud ...Staring past things ... Looking at things directly often robbed them of all their impact and meaning. I heard speech as only patterns of sound ... As an echolalic child, I did not understand the use of words. Any one or combination of the senses can become extremely sharp. For me this made some high-pitched sounds intolerable, bright light became either intolerable or mesmerising, and touch was always intolerable. (Williams, 1992: 186-188)

The most systematic and comprehensive account by a parent of the progress (or lack of progress) of an autistic child is Clara Claiborne Park's book The Siege about her autistic daughter, Elly, from which the following extracts are taken:She could look right through a person. She usually did. It was impossible by gesture to get her to look at an thing at a distance. ... her imperviousness to visual stimuli of all sorts. A car would draw up within three feet of where she was playing. She would not look at it. A dog ran past. She seemed to register nothing. She was over three before she looked up and saw a bird. But there were things she did not ignore:- colours, abstract shapes. The abstract meaningless, shapes seemed to have an intrinsic importance for her. That Elly wanted nothing was worst of all ... the child in the glass ball ... her overwhelming unwillingness to affect the environment. "Elly's signal lack of interest in future experience.For her out of sight is out of mind". (Park, 1972: 257)

Language peculiarities

More has been written on the language of autistic children than on any other of their psychological disabilities. Abnormalities of language are frequently reported by parents as being the first problem to give concern. The babbling sounds made by autistic infants are rarely as extensive in range as those made by normal babies. The speech cadences that usually develop by the age of 9 to 12 months do not appear. The National Autistic Society comment that it is virtually impossible to over-emphasise the importance of language to the developing child. A pictorial mind is completely inadequate and until one has a label for an object, one sees but does not remember it, so that in effect it does not really exist.

When the child does start to talk he sounds as though he is deaf, the voice is often monotonous and flat and as if speech is unnatural. Repetitive and stereotyped utterances take the place of novel and creative ones; abnormal and eccentric use of language almost as if the autistic person was speaking a foreign language. They seem to have to acquire language intellectually as one would have to learn Russian or Chinese. Conversation with an autistic child may be a matter of ritualistic questions and answers, with the child insisting on the mother asking a specific set of questions; if the mother varies, even in the minutest detail, the way in which she asks the question, the child may respond with a severe and prolonged tantrum.

Autistic children find differing degrees of difficulty in learning words belonging to different grammatical categories. Nouns are easiest to teach, easily demonstrated. Concrete verbs can be taught fairly easily too, most of them can be acted.The same can be done with words such as 'under', 'over', 'behind', 'in front', 'top', 'bottom', 'long', 'short', etc... The difficulty is with abstract words, and function words such as 'to', 'for', 'or', 'unless', 'until', 'while', 'as', etc. Even a child who has learnt to speak fairly well may ask what 'and' or 'the' means. 'Who', 'what', 'why', 'where', 'when', 'how', 'which', are difficult to teach. Most autistic children learn the word 'No' long before 'Yes'. An autistic child who is not echolalic will still have trouble with pronouns. This often leads to reversals: 'you' instead of 'I'.

Non-verbal communication of the autistic child

The understanding of non-verbal cues used by other people, such as gestures and facial expression, is severely affected. There is poor comprehension of the information conveyed by gesture, miming, facial expression, bodily posture, vocal intonation, etc. The strangeness and poverty of gestures in autistic children is noticeable, with absence of expressive gestures of the kind that usually accompany speech. Even very simple gestures, such as pointing, may be lacking. "Elly did not point. Nor did she try to get objects which were not within her reach; Elly is eight years old now. I have still never seen her point". (Park, 1972:12)

The following account is drawn almost wholly from Rita Jordan (1985). The use of signing with autistic children has been growing consistently since the early 70's. In 1983 half of the fourteen schools in Britain for autistic children were using some form of sign system. The hope is that the 'easier' sign language will provide a structure from which English can develop as a second language. The reasons why signing is 'easier' are probably multiple. The neurophysiological findings suggest that there may be differential disturbance of left-hemisphere brain functions in autistic children and there is some evidence that signing may be processed in the right hemisphere of the brain. Sign language is also more iconic than speech; autistic children learn iconic signs faster and retain them more readily than non-iconic ones.

Signs are promptable - they can be physically guided. It is easier to make individual signs distinct than to separate individual words from the stream of speech. In the light of the 'failure' of speech programmes, signing may be presented as a new activity - free from association with that experience of failure. All the studies report an increase in social awareness and a decrease in tantrums following the development of a system of communication. It is hoped that the child will learn to code his or her experiences and thus build up cognitive structures which are the basis for much later learning.

The most interesting aspect of the use of signing has been that often along with increasing ability to use signs has gone improvement in vocalisation and the ability to use words. So in the case of Gary, a three year old boy, who made a few sounds but who could copy simple gestures fairly readily, imitation of gestures was systematically encouraged until he could use such signs spontaneously to indicate his wishes. At the same time he began to vocalise more when using these signs although the vocalisations were generally rather indistinct.

Work by Creedon with 30 autistic children in America(see Jordan, 1985: 1) was very influential in that it offered hope that through signing a proportion of them at least would acquire speech. Along with overall progress in signing, some children developed spontaneous speech which gradually was produced more and more clearly. There has been the repeated observation that spontaneous vocalisations are often produced in conjunction with signs.

While learning to sign many children produce closer and closer approaches to the spoken word. According to Luria (quoted by Fay and Schuler, 1980: 160),body movements, particularly hand movements, facilitate speech production otherwise hampered by various types of brain damage . Such a facilitation effect may be related to the neural overlap that supposedly exists between oral and manual activities (Kimura and Archibald 1974). Activities of one neural region might trigger related action in adjoining areas.

But such a triggering effect has not been limited to signs. The spontaneous emergence of vocalisations that accompany hand movements was also noted by Carrier(1976) and Bonvillian and Nelson(1976). One might speculate that motor action might allow the formation of a representational framework for other action and thus reinforce the acquisition of meaning.(Tustin) The boy's progress [being taught signs] suggests that autism is a disorder of cross-modal perception rather than of symbolic functioning. (Fulwiler and Fouts 1976)

Reading by autistic children

This relation between speech and a non-articulatory system of communication is paralleled by an equally interesting relation between reading and the acquisition of language. What is surprising is that a sizable proportion of autistic children learn to read very effectively just as well [often] as non-autistic children of the same mental age. Some of these children learn to read early sometimes before they can talk; on hearing a new one word they may ask for it to be written or spelled and in this way it is unlikely to be forgotten again.

Park similarly observed "I cannot explain the strange reversal of the natural order of events in which a child learns speech through the written word. The configuration of letters itself seems to crystallise the word, makes it possible to hear its pronunciation, and renders its spelling an inseparable part of its identity. The look of a word could be used to help correct the indistinctness of her [Elly's] pronunciation. She could learn the look of a new word overnight; the job was not to retain the word itself, but its meaning".(Park 1972: 213 ff., 237)

Trevarthen(1990: 350) in his studies of child development has noted that the same progress also appears when deaf, hearing-impaired or hearing children are given early instruction in reading, an apparently more artificial form of communication, that, nevertheless, can start as a natural language at the middle of the second year; that is, as soon as a child can be expected to speak, or sign, single words, that same child, or one who is partially or profoundly deaf, can learn to read single words.

The motor theory summarised

Language is the capacity of one individual to alter, through structured sound emission, the mental organisation of another individual. Language is more than speech just as perception is more than the structure and functioning of the eye. In both cases we have also to be concerned with the neural organisation underlying the functions of speech and visual perception. The theory is that language was constructed on the basis of a previously existing complex system, the neural motor system. The programs and procedures which evolved for the construction and execution of simple and sequential motor movements formed the basis of the programs and procedures going to form language.

A principal theme is the mosaic evolution of language, the fitting together of a whole array of elements, anatomical, neural and behavioural. Many elements necessary for mosaic evolution of the language capacity can be found in the anatomical and behavioural repertoires of birds and other animals. If these animals have behavioural elements involved in the evolution of human language capacity, they must also have the neural structures required to produce the behaviours, and in particular the neural motor programs required. A mechanism for the development or acquisition of the elements, in evolutionary terms, must have existed. In humans, the evolution of language would have had a major survival value, particularly for the group which acquired language.

Two important behavioural elements for language are imitation and the categorical perception of speech sound - both abilities found in some animals. Imitation, of speech or other sound or bodily movement, involves a remarkable and complex linking of perception and motor organisation. The capacity to discriminate categorically between human speech sounds, has surprisingly also been found in a variety of animals - and in extremely young human infants. These and other behavioural prerequisites for language depend on the intimate involvement of the motor control system and the existence of cross-modal processes.

Development of the language capacity has resulted from the progressive establishment of new cross-modal or trans-functional neural linkages, cerebral reorganisation in the sense that the interconnectedness of different brain regions concerned with what are usually considered distinct functions has substantially increased. This extensive relation between language and the motor system is what one might reasonably expect, given the central role of the motor system in all behaviour and the essentially motor character of speech production.

The next step is systematic examination of the relation between each aspect of language and corresponding features of motor activity and the motor system. However, given the close relation between the use and content of language on the one hand and perception on the other, the examination naturally extends also to the relation between the motor system and perception in all its forms. The motor system forms the indispensable mediator between language and perception.

The essential additional hypothesis is that the motor system, prior to the development of language, was built up from a limited number of primitive elements - units of motor action - which could be formed into more extended motor programs. If this is so, then one can look for a direct correspondence between the primitive motor elements and the fundamental elements of spoken language, the phonemic system. The processes of word- formation and syntactic rules for constructing word-sequences would then be derived from the neural rules governing the union of motor elements into simple and more complex actions.

If language is in this way derived from the motor system, there is no reason to believe that any aspect of language - sound-elements, words or syntactic structure -is necessarily arbitrary. There is strong experimental evidence that the phonemic system is not arbitrary, and suggestive evidence that word-forms are not arbitrary but are expressive or appropriate to their meaning. There is also considerable evidence for a fundamental relation between the syntax of language and physiological syntax, the syntaxes of action and perception.

Recent research bears on the proposition that motor activity depends on a set of primitive motor elements. It supports the concept of motor programs and motor subprograms as real and not merely formal or theoretical bases for the organisation of action. Common general principles have evolved in neural control of movement in a wide range of animals. The experimental results suggest that the elementary motor programs may well be innate, part of standard human (and even vertebrate) neural structure. The elementary programs may form part of fixed action programs or be formed by a central motor program into novel action-sequences. In humans, research into motor programming bears directly on the relation between arm and head movements and speech.

The relation between motor programming and speech programming can be examined at the phonemic, lexical and syntactic levels. For phonemes, this leads to the idea of an invariant program for each phoneme, or 'auditory targeting', a motor-alphabet underlying speech, related to the elementary motor-patterns underlying other forms of action. Research on categorical speech perception has a direct bearing on this. A range of animals and very young infants have displayed the ability to categorise speech-sounds, natural or synthesised, in ways which match the category boundaries in adult speech; very young infants have been shown to discriminate categorically speech-sounds not found in their mother language.

On the motor theory, the categorisation of speech-sounds is derived from organisation prior to language, and specifically from the categorisation of motor programs used in constructing and executing all forms of bodily action. What the rhesus monkey, or the chinchilla, share with the young human infant is very similar skeletal and muscular organisation. The specificity of the phoneme is the accidental result of the application of the different elementary motor subprograms to the muscles which went to the form the articulatory system.

The link between the motor system and the formation of words follows. The hierarchical structure of the motor system is built on the basis of a limited set of motor elements. These are combined in an unlimited number of ways (motor-words). Words in speech are a read-out of neural structures in the same way as actions or facial expressions. A word, as a neural structure, can be formed from the co-activation of the motor subprograms for phonemes which are then melded or shingled together to form a distinct neural program for the whole word.

Experimental approaches with the creation of artificial words have suggested that there can be a lawful relation between speech-sounds and auditory or visual percepts. Research into sound-symbolism suggests that there is an isomorphism at the motor level between speech and the contents of perception. The object seen produces a motor-pattern which is readily transferable as a motor-program to the articulatory system and so becomes the associated word for the thing. The neuromuscular sequences which are the immediate motor programs underlying words are derived from the integration of the neural structures underlying perception in all its forms (visual, auditory, tactile etc.) and motor organisation.

It is of interest that in a recent book Hockett has commented on the relation between motor organisation and speech perception. "Although listeners obviously cannot have kinaesthetic feedback from someone else's articulation, they interpret what they hear by implicit motor- matching; actual movements of the organs of speech become unnecessary; the appropriate pattern of impulses within the central nervous system is enough".(Hockett 1987 39) If, as the motor theory proposes, phonemes and word-forms are derived from the motor system, then there must also be a close relation between the structuring of motor activity, motor syntax, and the organisation of language, speech syntax. One looks for evidence of this particularly in word-order.

Motor theory: features possibly relevant for autism

If autism is primarily a disorder of communication, or at the very least deficiencies in communication are one of the most grievous effects of autism, a number of aspects of the motor theory may be relevant. Neural organisation The role of language is to produce changes in the mind (changes in the brain) of the hearer which structurally resemble those in the mind (brain) of the speaker. This would apply to other systems of communication, gesture, sign languages, facial expression, and to instances where communication is mediated in space or time e.g. written language.

The content of all utterances, messages of any kind, ultimately will be represented by changes in synaptic strengths, establishment of new excitatory or inhibitory connections, dendritic growth. Crossmodal processes Any utterance, any message however delivered, looks for a response, which may be immediate action, or delayed action.For the action to take place. there must be the necessary crossmodal links between different brain functions. Equally there must be the crossmodal links for the production of any utterance, gestural message etc.

Motor system centrality All behaviour in evolutionary terms is a matter of motor primacy, and all types of communication in relation to the autistic child should be examined from this perspective. Primitive motor elements (programs) Because of the limitations of the human (and other) brains - there cannot be preformed neural programs to provide for every possible sentence or every possible action - and the demands of an unpredictable environment, communication systems have to be open-ended, relying on a limited set of primitive elements which can be combined to meet the needs of any situation. How far do autistic children possess. or have effective use of, such a system of primitive elements?

Categorical perception Production and perception of spoken language and other forms of communication must have evolved together. In the normal case,there must be provision for extracting primitive elements or combinations of the elements reliably from the incoming utterance or message.

Non-arbitrariness Insofar as the motor elements are the product of evolution of neural organisation, language rests ultimately on a non- arbitrary basis; the same is probably true for other forms of communication, gestures, facial expression etc..

Hierarchical pattern of system Motor control is a hierarchical process, with relevant parameters being fed in at the appropriate level. This is a necessary organisational economy.The primitive elements must be capable of being melded together to form higher-level structures, to provide a "lexicon" to match the multiplicity of objects or actions.

Derivation of second-level patterns from the structure of perception The particular structure of words is derived from the structure of the perception or action to which the words refer. This link between language and perception may be of particular importance in considering the communication problems of autistic children.

Extended sequences The syntax of spoken language is based on motor syntax. Motor syntax may also be a source for the organisation of extended sequences in other forms of communication. In the autistic child is normal motor syntax deficient, or is the relation between speech syntax and motor syntax lacking?

Causes and treatment

So far the underlying condition of autism has been untreatable though many meliorative forms of treatment have been tried, with limited success. There is no consensus about the fundamental causes of autism. It is more clear what autism is not rather than what it is. Autism is not just a variety of mental retardation or a form of childhood schizophrenia. There are three principal theories, competing but not necessarily mutually incompatible. The first is that autism is the product of faulty emotional attachment between the parent and the infant. Treatment flowing from this approach concentrates on breaking down parent/child emotional barriers. This approach is not accepted by most of those working professionally with autistic children insofar as it implies that parents are to blame for their children's autism.

The second theory is that there is an important genetic component - this indeed seems likely but does not go far to explain the character of autism or to indicate how it should be treated. The third theory is that there are faults in pre-natal and post-natal neural development, in the maturation of the brain. Neural connections which make possible the transfer of experience from one sensory modality to another are not made or are not functional. In the absence of the normal translation of sensations into percepts and concepts, the autistic child is unable to organise appropriate response to the outside world.

How does this kind of approach relate to, have points of contact with what the motor theory proposes? For language, the theory suggests, there must be the development of neural connections linking perception, motor control and language. Only if this happens will the child find it easy, natural, to acquire the phonemes of whatever happens to be the mother-language. Only if these neural connections are made will there be an easy and natural relation between the structures of words and the visual (or other) percepts or actions to which the words relate.

Only if the necessary neural connections between neural motor sequencing and language sequencing will the infant be able easily and naturally to acquire grammatical features,, the concept of word-order, the use of function-words, etc. The emphasis laid by the motor theory on the cross-modal aspects of language, on language in use as a continual neural restructuring, on the vital importance of the primitive motor-elements, seems to have very direct relevance.

Practical suggestions flowing from the motor theory

But where does this lead in practical terms? This depends on some hypotheses about what may have gone wrong, what may be missing in the autistic infant's patterns of neural connectivity. At the worst there might be lack of the primitive motor programs - if that were the case then the child would be spastic, and autistic children are not spastic. Typically, they can move, see and hear. Or the link between articulation and perception and the primitive motor programs may not have been made.

The peculiarities of vision, the tendency to use others' hands rather than their own, the curious lack of dizziness in spinning round, do suggest that there may be something wrong in the relation between the motor aspects of vision and central perception. Or there may be a lack, a distortion, of the relation between the primitive motor programs and the patterning of articulation. This would explain both the defects in the production of speech sounds and the absence or difficulty in the perception of speech sounds. Or there may be deficiency in the neural links between motor sequencing and speech sequencing, which would explain confusion in word- order as well as confusion in the ordering of phonemes in a word.

What might be done by way of treatment, or training, in the light of this? That motor methods may be practically useful has been shown by the relative (though still limited) success of treatment developed by Doman and Delcato.(Doman 1974) This involves physically moulding the pattern of movement of the children so that they perform the same motions in the same stages as those which normal children go through in, for example, learning to walk. How the theory of the motor basis of language might be translated into practical forms of treatment is speculative but some possibilities seem to be:

1. Emphasis on improving the autistic child's motor abilities. A number of forms of treatment (besides the Doman-Delcato approach) already do this. Some autistic children, as they get older, in fact demonstrate skilled motor control in piano playing, drawing etc.

2. Emphasis on the strengthening in every way possible of cross-modal links: gesture and speech-training should be linked together. The characteristic attention of autistic children to abstract shapes should be exploited - maybe the curious ability with which they can use written letters and learn to read is a manifestation of this. They should be encouraged as early as possible to associate the shapes of letters with speech-sounds, the shapes of words with pictures of the things to which the words relate; associate appropriate hand and arm movements with reading a word describing the movement.

3. The link between basic motor programs and the patterning of articulation is of critical importance. There should be a systematic linking of bodily movement and the production and perception of speech sounds. They should be taught to correlate a pattern of arm movements with an ordered set of speech sounds.

4. For improving retention of words and their meanings, use iconic gestures and associate the sound of the word with the gesture. It does not matter much whether the gesture is part of an established sign language (ASL or BSL) but the more iconic, even pantomimic, the better. Do not rely only on imitation of the gesture by the child; form the movement for the child, following the Doman approach. Accompany a word describing action with the action to which it refers e.g. jump with 'Jump' - hit with 'Hit'.

5. Try to develop a direct relation between action-syntax and speech- syntax. The child should be encouraged ( or the child's movement directly patterned) to match specific actions with specific word-orders: "I give the cup to Mary " etc.

6. Pronouns are directly derived from deictic gestures. The pronouns should be associated with these gestures. It is very important that the child should be encouraged to point, to himself or to others or to things. Associate pointing (forming the child's arm position) with the pronouns: YOU with pointing to someone else and ME with the hand pointing to the child's chest

Conclusion

The main idea of the motor theory is that the structures of language, (phonological, lexical and syntactic) derive from and are modelled on neural patterning for motor control. Motor programs for the control of bodily action, by a growth in neural connectivity, became extended to the control of articulation so producing the restricted and specific range of speech sounds found in all human languages; the structures of words were derived from the motor patterning involved in the perception of objects in the external world and from the motor patterning of the actions to which words refer, and syntactic organisation of language reflects 'syntactic' processes in the planning and execution of bodily action.

The aspect of the motor theory of language origin and function which may be particularly relevant for autism is this: perception and motor control in the normal individual are, and must be, intimately linked (so that we can, for example, see an object and stretch out our hand to pick it up). If language is derived from and closely associated with the patterning of motor control, then perception, motor control and language must in neural terms be locked together. For language to develop normally, the neural connections with the motor system must develop at the appropriate time.

If they do not, then even if the relation between perception and motor control is normal, the link between the object perceived (scanned by eye-movements) or the action executed or perceived and the word structurally related to the object or action cannot be established. Without the necessary and natural link between word and object or word and action, all the potentialities of higher-level mental functioning, the manipulation of concepts, rational thought, imagination, planning, would be crippled. Meaningful gesture, a motor activity intimately related to speech and seen by many as an integral aspect of speech production, would be defective or absent.

The autistic child lacks language, or has only severely defective language; at the same time the autistic child is abnormal emotionally, both in the lack of empathy with others and in its heightened sensitivity: as Donna Williams describes it, a hyper-emotional response to everything from the outside world. In autistic behaviour, what are causes and what are effects? Does the abnormal emotional response cause the failure to acquire or use language normally, or does the lack of normal language create the hyper- sensitivity, the abnormal emotionality?

The autistic child appears to lack the step in cerebral reorganisation (neural connectivity) which made language possible; this is a critical loss. Language, vision and motor control all go together; language is the supreme medium of empathy and language almost certainly plays the major role in making possible consciousness, self-awareness; language allows one to construct a model of one's world, to create rational expectancies, particularly about the behaviour of others. For someone with no reliable pattern of expectation about the 'world', every moment of life becomes like wandering through a Chamber of Horrors, unknown and unexpected horrors.

Perception is perception of change in the environment. To perceive change, the perceiver must have retained the pattern of the normal,the stable, the usual, the expected. The source of any change may be the inanimate environment (wind, rain, cloud), the animate environment (conspecific or other specific), the individual human environment, or the social environment. Language is both itself perceived change in the human environment and the means for controlling, categorising change. To make possible the perception of change, there must be appropriate neural organisation, a neural record of the expected environment. The perceptual capacity of the perceiver derives from the model it retains of its environment and of itself as acting within that environment.

Our brains must be structured in terms of the usual or expected environment and perception is the result of interaction, or matching between the expected environment and the current environment by which change is detected. Perception would then be a direct reflection, an internal representation of reality, internal ordering guided by external ordering. Language would be the instrument for controlling rather than being controlled by perceived change.

The autistic child's hyper- emotionality, hyper-sensitivity, would be the result of the lack of language, of all means of social communication. If this is right, then any approach, any treatment, that reduces, even if it does not cure, the deficiencies of language, should carry with it the prospect of general gains in behaviour, in sociability, in emotional control.

REFERENCES

Bonvillian, J.D. and K.E. Nelson. 1976. Sign language acquisition in a mute autistic boy. J Speech Hear Disord. 41(3):339-47.

Doman, Glenn. 1974. What to do about your brain-injured child. London: Jonathan Cape. Fay, Warren H. and Adriana Luce Schuler. 1980. Emerging Language in Autistic Children. London: Edward Arnold. Frith, Uta. 1989. Autism: Explaining an Enigma. Oxford: Basil Blackwell. Fulwiler R.L. and R.S. Fouts. 1976. Acquisition of American sign language by a noncommunicating autistic child. J Autism Child Schizophr. 6(1):43-51. Hockett, C. F. 1987. Refurbishing our foundations: Elementary linguistics from an advanced point of view. Amsterdam/Philadelphia: Benjamins. Howlin, Patricia and Michael Rutter. 1987. Treatment of Autistic Children. Chichester: Wiley. Jordan, Rita. 1985. Signing and Autistic Children. Communication: Sept/1985. Kimura, D. and Y. Archibald. 1974. Motor functions of the left hemisphere. Brain. 97(2):337-50. Luria, A.R. and F. Ia. Yudovich. 1971. Speech and the development of mental processes in the child. Trans. O. Kovasc and J. Simon. Harmondsworth: Penguin. Park, Clara Claiborne. 1972. The Siege. Harmondsworth: Penguin. Schopler, Eric and Gary B. Mesibov eds. 1988. Diagnosis and assessment of autism. New York: Plenum. Trevarthen, C. 1984. How control of movement develops.In Human motor actions: Bernstein reassessed. ed. by H. Whiting, pp. 223-261. Amsterdam: North-Holland. Trevarthen, C. 1990. Growth and education in the hemispheres. In Trevarthen, C., ed. Brain circuits and functions. CUP, pp. 334-363. Tustin, Frances. 1980. Autistic states in children. London: Routledge & Kegan Paul. Williams, Donna. 1992. Nobody Nowhere. London: Doubleday. Wing, Lorna. 1971. Autistic Children: A Guide for Parents. London: Constable