Problems of Auditory Processing as a Key Feature of Autistic Spectrum Disorder (Autism)
R E Seymour
The Autism Society of America describes autism as:
“…a complex developmental disability that typically appears during the first three years of life. The result of a neurological disorder that affects the functioning of the brain, autism and its associated behaviours have been estimated to occur in as many as 1 in 500 individuals (Centres for Disease Control and Prevention, 1997). Autism impacts the normal development of the brain in the areas of social interaction and communication skills.” ASA, 2000.
The Geneva Centre of Toronto reports statistics that show an incidence of 1 in 200. The California Health and Services Agency report to the legislature, 1999, states that the incidence of autism has increased dramatically relative to other developmental disabilities, and that “the accelerated rate appears to be sustaining an upward trend into future years.” A number of recent surveys currently place the incidence at 1 in 90. Autism is four times more prevalent in boys than girls, and knows no racial, ethnic, or social boundaries.
The clinical picture of autism can vary greatly among individuals. No single behaviour defines autism, but rather a cluster of behaviours, and the intensity to which they are displayed. This variability of the clinical picture of autism, and its tendency to change with age, and its potential co-occurrence with other developmental difficulties, leads to significant difficulties for diagnosis of this condition. In 1998 Dr Lorna Wing introduced the concept of a spectrum of disorders in autism, to assist in the understanding of this variability.
It is internationally accepted practice to express the diagnosis of Autism with reference to this spectrum of potential behaviours, degrees of handicap, degrees of ability, and associated problems.
In the USA, Autism is described in the categories outlined in the Diagnostic Standards Manual - IV (1994) of the American Psychiatric Association, namely :
- Impairment in the quality of verbal and non-verbal communication; (receptive and expressive.).
- Impairment in the quality of reciprocal social interaction.
- Markedly restricted repertoire of interests and activities, that may include obsessions, fixations, and repetitive movements, and usually includes resistance to learning.
- The Autism Society of America also emphasises that individuals with autism may experience various problems with sensory feedback or processing of sensory information.
There are attempts to deal with the diversity of clinical pictures by identifying different ‘types’ of autism, such as Kanner’s, Asperger’s, Pervasive Developmental Disorder (PDD), Rett’s Syndrome, Childhood Disintegrative Disorder. The criteria for these are outlined in the DSM - IV.
In the United Kingdom, autism is defined somewhat differently from the USA. While it is agreed that autism is of biological origin, the focus is on cognition - on the ‘triad of impairments’; i.e. socialisation, communication, and imagination. The emphasis is on the ‘theory of mind’ - the ability to ‘mind-read’. This is the feature said to be universally deficient in autism, according to Uta Frith, Alan Leslie, and Simon Baron-Cohen (Happé, p 50). Baron-Cohen has written much on the ‘mentalising’ problems, or ‘mind-blindness’, of the autistic condition.
The DAN! (Defeat Autism Now! 1992 to the present) initiative of the Autism Research Institute of Dr. Bernard Rimland, has promoted a greater awareness of the biological disorders common to children (and adults) with autism. The scientists and specialists involved have demonstrated the effect of certain biological processes on brain functioning, and particularly the problems of brain functioning that are typical of autism. Some scientists now define autism as “a condition of neuro-biological origin” ( S.M. Baker & Jon Pangborn, 1997), and there is speculation that autism may in fact be a disorder of the gastro-intestinal tract, with the resulting toxins affecting brain function and development (Shaw, W; Horvath, K; Wakefield, A; Reichelt, K, in their papers at Barcelona, 2001).
Although the view of autism differ, most researchers agree that there is no known cure for autism. It is often described as a “severe life-long condition”. This view has received some significant challenges. Evidence is mounting to support the possibility of recovery from autism, at least for some individuals. Rimland describes incidents of ‘spontaneous recovery’; of ‘significant recovery’ (Grandin 1986; Sean Barron 1992; McDonnell 1993); and of ‘partial recovery’ (Williams 1992, 1994). Recovery attributed to known causes include: Tony Callan 1997 (milk- free diet); Georgie Stehli 1991 (Bérard AIT); the ‘Maurice’ children 1993, and Drew 1994 (Lovaas ABA).
For most children with autism, it appears that intensive, structured, multi-faceted intervention offers the best possible outcome (Greenspan, Stehli, and Giant Steps)
While education (cognitive) is the most-frequently applied intervention, there is increasing evidence that dietary (metabolic) interventions provide the more favourable outcomes (DAN!). In addition, there is increasing evidence of the need for and value of including intensive sensory interventions. (Williams, Bérard, Blackman, Grandin, Stehli, Tomatis )
Sensory Difficulties In Autism
Unusual responses by children and adults to sensations have been described by Jean Ayres (1979). These are indicative of problems with sensory processing that underlie various developmental difficulties. This concept has been elaborated by Fisher, Murray and Bundy in their book “Sensory Integration” (1991). Drs Courchesne (1987), Delacato (1974), and Ney (1979) were among the first who investigated the problem of altered sensory processing in autism. Kanner (1943) had noted the childrens’ unresponsiveness to certain sounds. Accounts from case studies abound indicating sensory processing or modulation differences in people with autism ( Grandin, Stehli, Williams, Delacato). Dahlgren and Gillberg (1989) point out that the appearance of sensory differences may be the first indication that something is wrong with the child who is later diagnosed with autism.
Of all the sensory modulation problems that beset people with autism, poor auditory modulation seems to be one of the most problematic. It is a difficulty that hampers attention and concentration, as well as sociability and the development of communication (Stehli, 1991; 1994; Williams (1999) First-hand reports by people with autism describe the distress and confusion that result from inadequate auditory modulation. (Williams, Grandin, Stehli ). Courchesne, Lincoln, Kilman and Galambos (1985) found the neurophysiology for auditory modulation to be more impaired than the visual, in people with autism.
Auditory Problems in Autism
Tomatis (1970), Koegel & Schreibman (1976), as well as Hayes and Gordon (1977) have linked problems of auditory modulation to behavioural and attention problems, and to speech and language difficulties, and to dyslexia. Katz and Kusnierczyk (1993) have described auditory modulation disorders according to their effect on processing speed, on speech-in-noise processing, hypersensitivity, poor attention, auditory-visual integration, sequencing, and auditory memory problems. They demonstrate that these auditory problems will hamper reading and spelling, and comprehension.
Katz and Wilde point out that it is common for children with auditory processing disorders to come to the unfavourable attention of school staff and even the police. It seems clear that the impact of auditory processing problems on an individual can be profound. Dr Guy Bérard has entitled his book “Hearing Equals Behaviour” to emphasise this link, and he describes the improvements in attention, responsiveness, behaviour, speech and language that occur when auditory sensory modulation improved.
Delacato (1974) documented how a child could be unresponsive to certain sounds (act as-if deaf), but have an exaggerated response to other sounds. Dr Bernard Rimland (1964) indicated that his research found 40% of people with autism to suffer from hyper-processing of the auditory stimuli, or ‘hyperacusis’. From accounts, it appears that this hyper-hearing leads to social withdrawal, speech problems, and overload behaviour in the form of tantrums and aggression.
However, over-sensitive hearing is not the only auditory symptom of the poor modulation of sound that is common in autism: Wong and Wong (1991), Courchesne (1987), and Condon (1975) have described longer transmission time in the brainstem, resulting in slow processing of sound. Tallal (1996), Merzenich et al (1996) , and Kraus et al (1996) found that children with ‘language-based learning impairments’ had major difficulties with ‘temporal processing’ at brainstem level. That is, the brainstem cannot adequately process rapidly-changing sounds as in speech, and thus cognitive auditory functions will be negatively affected leading to comprehension problems and learning difficulties.
Bauman and Kemper (1994), found brainstem and cerebellar differences in autism, indicating structural bases for sensory processing problems. Rosen and Galaburda (1995) have found structural differences in the medial geniculate nucleus of the brainstem – which is also an area for processing fast-changing sounds.
Cerebral blood-flow studies by Garreau and associates (1994) revealed the autistic auditory response to be atypical (right hemispheral) compared to non-autistic listeners (left hemispheral).
It is evident, then, that sensory processing or modulation differences in autism can underlie the well-documented cognitive defects of people with autism, and may even lead to severe challenging behaviours. Of these differences, research seems to indicate that the auditory is often the most severely disrupted, with implications for communication, speech and language, and socialisation.
Auditory sensory modulation problems have received little attention in autism, except for the symptom of painful hearing (hyperacusis). The management of this has been through wearing of earplugs (Delacato), or metabolic intervention through taking magnesium supplements with vitamin B6. This has seemed to be effective in some cases (Rimland – website of Autism Research Institute ).
The first auditory technique to have been developed, was the ‘oreille electronique’ , by Dr. Alfred de Tomatis, described in his book ‘Education et Dyslexie’ in 1962. His theories and practice were hailed by a storm of criticism, as is the typical response to new ideas. This approach first gained acceptance in Canada, and then internationally. It has recently become a widely accepted, even fashionable treatment.
A former colleague of Dr Tomatis, Dr Guy Bérard revised the basic concepts underlying the ‘electronic ear’, to shift from the emphasis on emotional ‘bonding’, to focus upon the mechanics of the hearing response. Through re-working the application he was able to achieve more significant changes in a shorter time of intervention.
In recent years, there have been many adaptations of these two doctors’ theories and techniques: e.g. Samonas, Johansen, Digital Auditory Aerobics, and Ease-Disc. Other auditory attention-altering approaches have also come to the fore, e.g. BioAcoustics, Fast ForWord (Tallal), Hemi-Sync, Structured Listening, and Interactive Metronome.
Changes in behaviours have been reported along a wide spectrum of possibilities, behavioural, attentional, and communicative (Veale, 1993; Bérard 1993; Stehli ed. 1995).
The Bérard Method of Auditory Integration Training As An Intervention for Autism
In 1991 the release of the book “The Sound of a Miracle - A Child’s Triumph Over Autism”, by Annabel Stehli introduced Auditory Integration Training (AIT) - the Bérard Method to the English-speaking world. In this account, a mother tells of her daughter’s Georgiana’s recovery form autism. This girl had been diagnosed by several reputable autism specialists in New York, USA, and had received various structured, carefully-monitored therapies. However, the parents, and Georgie herself, ascribe her breakthrough recovery to this ten-day auditory training which, in their opinion, opened the door to the progress that followed. International public and professional interest has led to this method being practised in most countries in either its original form or some adjusted format.
Dr Guy Bérard, a French Ear-Nose- and Throat Specialist in France, devised this new auditory re-training technique. His book describing the process was translated into English in 1993 as “Hearing Equals Behaviour”. His technique had been practised in Europe and Canada for approximately 30 years before the English translation was published. Dr Bérard devised AIT in response to his own progressive hearing loss. Besides benefiting his hearing problem, AIT was found to be an effective auditory training method with a much wider application than hearing loss. It is used as an auxiliary intervention for conditions in which hearing (or, more properly, ‘listening’, or auditory processing, ) plays a significant role.
AIT was soon found to benefit children with autism in unexpected ways. Beyond assisting them with their dyslexia or speech/language development, there were improvements reported in responsiveness, activity levels, sensory processes, and social skills, and even their sense of well-being. AIT has been reported to be helpful to children and adults alike. It seems to have benefits for those with or without diagnoses, as a tool for improving listening skills. That is, anyone who needs to listen, for any reason, can benefit from listening training.
AIT began to receive widespread media attention as a useful intervention in autism. The growing public interest prompted research into the validity of AIT, to determine whether there was substance to any of the anecdotal reports by parents and practitioners of improvements. To-date, there have been approximately 28 published studies, with several of these appearing in peer-reviewed journals for speech therapists and audiologists, and the journals for autism. Although it is not a treatment for autism as such, many studies have focused on the effect of AIT on autism. Clinical outcome studies have tended to validate reports that AIT brings about changes in a wide variety of areas of functioning, with no reported long-term negative effect, nor risk of causing harm. (for a critique of these studies, see www.georgianainstitute.org).
Since 1992, many practitioners of Bérard AIT have been certificated and provide this auditory training in many countries around the world.
The Listening Test and Course of Sessions
It is necessary here to clarify the misconceptions about auditory testing for AIT: the auditory testing of people with autism just for the purposes of AIT is a practice that Dr Bérard does not support.
He states as reason the inadequate levels of reliability of the responses of people with autism to behavioural or response audiometry. However, where it is possible to readily obtain a reliable audiogram or listening graph, these results might be useful to indicate the desirability of setting the additional specific filters. However, at this time research supports the belief that AIT proceeds effectively without the additional filter settings (Rimland and Edelson, 1994).
The practitioner may find indications to set some specific filters depending on the client’s listening graph, if an accurate one could be obtained. The sessions proceed in a manner likened to an aerobic or exercise programme - commencing with mild exertion and increasing to optimum levels. This level of exertion relates to the loudness of the sound input. Sound levels are kept to within the determined levels of safety, and no auditory risk is posed by AIT.
This method does not require the client trying to listen, nor application of the conscious mind to the task. It seems that in AIT the mechanisms of the ear receive a ‘passive massage’, and this has the effect of ‘toning up’ or ‘tuning in’ the listening mechanism.
Following the ten-day course, no further action is recommended specifically to enhance the benefits of the course. No ‘top-up’ sessions are required or recommended. It is however most important to ensure that the child does not use headphones to listen to music (e.g. walkman, MP3 ). The Client must avoid exposure to loud music – as in disco music, etc. Another feature to ensure AIT benefits are not lost, is to ensure that there are no ongoing dietary imbalances or neuro-biological conditions left untreated.
It is recommended to wait for three to four months after the training before finally assessing the results of the intervention. After an interval of 9 to 12 months the process may be repeated, often with continuing benefit.
Changes in behaviours have been reported along a wide spectrum of possibilities, behavioural, attentional, and communicative (Veale, 1993; Bérard 1993; Stehli ed. 1995). Reading the research reports on AIT gives an indication of the kinds of results one may expect from a course of AIT.
The list of references is available on application to the author.