Whether the latter idea is true or not has yet to be determined but the evidence of abnormal perceptual experiences has come, over many years, from people with autism themselves. They repeatedly comment that their tactile, auditory and visual experiences are, in some way, different to those of most people. Unfortunately though some professionals remain sceptical, and continue to dismiss such accounts as anecdotal.

These conflicting ideas result in confusion and create considerable doubt about the efficacy of treatments said to alleviate the sensory problems. Is there any way to clarify this confusion? Certainly if such problems actually exist it should be possible to describe them and assess them in some way: as is now possible for both the auditory and the visual problems.

Auditory problems
Apart from deafness and partial hearing loss there are several less well known auditory problems found both in the general population and, to a greater extent, in people with dyslexia and autism. These are:

Problem: Effects:
Auditory dyslaterality - hearing some sounds Slowed auditory perception. Problems
well with one ear whilst hearing them only of interpretation as letters are lost or
partially or not at all with the other ear. their sequence is misheard.

Inability to habituate to (cut out) particular Loss of concentration in situations
sounds (as most of us do e.g. when sleeping with background noise - especially
near a noisy road). social situations. Disrupted sleep.

'Supersensitive' hearing - found in the child Generally not perceived as a problem
who can hear a 'silent dog whistle' or the 'far end' but may be factor in hyperacusis -
of a telephone conversation. (i.e. hypersensitivity to sound).

Hyperacusis - often associated with tinnitus. Avoidance of particular situations. Makes
Stressed by particular sounds that do not socializing, shopping, travelling etc.
bother other people. Such sounds generally extremely difficult.
seem much louder than they actually are
& the person is unable to block them out easily. The sounds are individual & can include people eating, television, vacuum cleaners & also quieter sounds like a zip being pulled. Hyperacusis is also found in over 40% of people with tinnitus as well & may prove to be a factor in the development of some tinnitus.

It is important to note that hyperacusis is different to an overall hypersensitivity to sound which is often associated with a lack of certain minerals and can increase in stressful situations.

Loudness discomfort. The majority of people can tolerate sounds up to 100 decibels but some people with autism have a far lower tolerance.

Auditory problems in autism.
Many people with autism have one or more of these auditory problems. These problems can leave the child unable to concentrate properly as extraneous sounds constantly impinge upon him. Thus when listening to others the child may hear a single word or two or even a simple sentence but longer sentences may be 'broken up' by intruding background noises and the meaning lost: as it is if you try to listen to a badly tuned radio.

Some certainly have hyperacusis as did Georgiana Stehli (diagnosed with autism as a child). She was so badly affected by some sounds that, as she told her mother, 'The sound was the only thing that drove me crazy because I was so scared . . . and sound was going on all the time. It was hard to get away from it. ………….' (Stehli 1990, p.188)

Small wonder that such problems can lead him to avoid, run away from, or block out the noises he dislikes - blocking out many important sounds as well and thereby losing a valuable aid to learning and communication.

Visual problems.
Approximately 70% of information about the world is taken in through the eye. Unfortunately there are a group of visual perceptual problems (known by various names such as visual discomfort or Scotopic Sensitivity - Irlen - Syndrome) which may remain unidentified by an ordinary eye test but which, once found, can often be remedied by the use of tinted lenses.

These perceptual problems affect some 15 - 20% of the general population and approximately 50% of people with dyslexia, some of whom also have conditions such as migraine, allergies or hypoglycaemia. A family history of migraine, allergies, dyslexia or hyperactivity is also common.

When the condition is mild the person may learn to adapt to the difficulties and will experience few problems apart from headaches or migraine. Those with moderate problems could have a range of 'dyslexic' type difficulties when reading or writing.

The following list identifies some of these visual problems, several of which are linked to poor coordination between the eyes:

Problem Causes:
Photophobia - sensitivity to glare Discomfort, headaches or migraines when reading or
brightness or fluorescent lights. problems when driving at night. Words 'get lost'
when reading and the paper may appear to glare.

Unexplained loss of visual Sees things as darker than they actually are - losing
acuity much of the features, fine detail and colour.

An insufficient ability to focus. Impairment similar to tunnel vision in which a small area
of page is clear but the surrounding area is blurred.

Difficulty in sustaining focus Tires easily when reading, suffer headaches or eyestrain.
without great effort. Print seems distorted - running together/moving. The
background may also glare or dominate.

Poor depth perception. Clumsiness, problems when throwing, catching, judging
height or width, walking down stairs.

Severe visual perceptual problems.
Accounts from people with autism and Asperger's Syndrome as well as the work of the Irlen Institute now indicate that such problems may also affect people with autism and Asperger's Syndrome, causing a wide range of difficulties which are generally more severe than those found in dyslexia.

So how things might look to a person who had severe scotopic sensitivity. Focusing problems and poor depth perception are relatively easy to understand but what of photophobia and that unexplained loss of visual acuity?

You can simulate the effects of photophobia for yourself by looking at things under a very bright light. As you will see the features of faces fade although distinct points such as the nose or a beard may remain readily identifiable. Background details will be leeched of colour though making it more difficult to identify them correctly. It is easy to see that under some lighting conditions, people and objects would appear fragmented. Not only would this make life extremely confusing and frightening but, in real life, movement and different lighting conditions would mean that the 'picture' was constantly changing.

In contrast wearing darken glasses indoors on a dull day (without putting the lights on) will enable you to replicate a loss of visual acuity. Once again you will find that features on faces become less clear, especially around the eyes, although a white tooth stands out. The background details become far less clear and some of features may merge into each other. This will make it hard for you to identify the expressions on the faces or accurately see just where one object ends and another begins.

One additional problem was identified by Georgiana Stehli who saw things as if they were magnified - a strand of hair looked like a piece of spaghetti - and could also see lines, shapes and colours that most other people would have been unaware of. While the object focused on will seem much larger than normal, things on the periphery become blurred or 'lost'. Imagine how weird and confusing the world must seem if viewed in this way.

Where such problems exist it is easy to imagine the difficulty of recognizing people and objects correctly. Could they also explain why people with autism have difficulties in understanding the emotions of others and in interpreting body language? Do they actually see the smile on your face or your gestures correctly? Doubtful when you consider that Gunilla Gerland talks of 'people with blank faces' in her book? Given that similar problems can leave the person with dyslexia 'word blind' I would suggest that the more visual severe problems found in autism could leave the person 'meaning blind'.

What should be done?
There are three options. One is to ignore such ideas totally, continuing to think in terms of "abnormal reactions to stimuli". Certainly it is easy to attribute bizarre behaviours solely to the problems of autism. And yet - what if the problems really exist? Would you leave a child who had a hearing loss or who was short-sighted to struggle with their problems rather than having them assessed and treated? Of course not - and yet that is the implication of this option.

Second is to use various techniques to help the person learn how to cope with such difficulties - eg by using earplugs - which is a good idea when treatment does not exist. However treatment does exist for both the auditory and visual problems mentioned. Thus the third and most sensible option is to have such problems assessed and, where they are found to exist, to treat them.

How will you know if your child has auditory problems?
While any hearing assessment should include tests to assess hyperacusis and loudness tolerance it is worth noting that older children and adults with autism or Asperger's syndrome may be so adept at blocking sounds that test results could be misleading and parents' memories of early childhood reactions will need to be taken into account. The checklist below will give you some indication as to whether or not treatment would be beneficial.

Indications of severe auditory difficulties.

Often ignores sounds/speech but reacts readily to some noises eg sweetpapers crackling.
May initially be considered deaf.
Speech difficulties - e.g. speech does not develop (but is not deaf) or development is slow; echolalia; speaks clearly but only occasionally; consistently mispronounces some words.
If given two instructions is only able to carry out one task or does neither.
Dislikes some noises and demonstrates this by:-
putting his hands over/in ears
moving away
getting upset or distressed
going into 'a world of his own'
And/or spends a lot of time listening to music - often quite loudly.
A very light sleeper - wakes easily.
Frightened of some animals - especially household pets.
Seems to hear noises which other people might not be aware of eg the hum of fluorescent lights, people breathing etc.
Can often correctly identify distant noises (before others hear them) or can overhear distant conversations eg both sides of a telephone conversation
Dislike bathing, haircut's, shaving, teethcleaning etc. because of the noise of the water, scissors, razor etc.
Finds mealtimes difficult as dislikes the sound of people eating
Dislike the sound of a toilet flushing.
Dislikes shops, crowded situations, shopping, rainstorms, wind, seaside etc.
Learns/concentrates better in quiet surroundings.
Enjoys/seeks music or loud rhythmic noises i.e. washing machines, vacuum cleaners, lawn mowers.
Enjoys being in control of noisy objects - eg likes playing with running water, flushing the toilet etc.
Likes/does things that make a noise; squeaking toys, tearing paper, banging doors etc.
Talks constantly/loudly.

Treatment
Auditory Integration Training (AIT) was developed by Dr. Bérard who used it to treat people who had a wide range of difficulties, including depression, dyslexia, learning difficulties and autism; the common link being some type of hearing anomaly.

AIT still has some critics but the results (many of which can now be found on the Internet) generally indicate that it can have positive benefits. Even though the method by which it works is not fully understood, treatment effectively 'retrains' the hearing, correcting some hearing distortions and undersensitivity whilst desensitizing those with hyperacusis and increasing tolerance of previously uncomfortable noise levels.

The benefits of AIT
While the results are obviously dependent on the initial problems they include:
· improvements in the ability to listen, concentrate and learn.
· increased sociability and communication
· reduced hyperactivity - less impulsive and distractible.
· improved behaviour, clearer speech.
· increased concentration, better memory and understanding.

How do those who have undergone treatment actually feel about it? Let them explain. The following quotes are taken from Dancing in the Rain edited by Annabel Stehli. The first quote is from a six year old who said 'The motorcycles are gone from my head, and I can still hear people blink but I can tune it out.'

Second is Charlie who, a month after AIT, said, 'when I laugh it doesn't bother me anymore.' To repeat his mother's question 'Can you imagine your ears hurting when you laughed?'

Third is Sharisa who has undergone Auditory Training twice and is therefore well qualified to comment upon the results. As she says '. . . . AIT has enabled me to sleep better, be calmer while I'm awake, and understand what I hear more quickly and clearly. I can handle noises which had previously caused me to withdraw or panic. These included applause, sirens, dogs barking, vacuum-cleaners, dishwashers, certain voices, the sound of fluorescent lights, or piano music, computers, and sound of the ocean. I believe it also reduced sensitivities in sight, smell, taste, and tactile sensations. I'm much, much happier and less inclined to anger.
(Stehli 1995, pp.86,100.)

Assessment and Treatment of Visual Perceptual Problems
The recognition of this type of visual perceptual problem amongst some people with autism and Asperger's syndrome is an exciting development and the preliminary results offer the hope that some of the most devastating consequences of these can at least, be overcome.

Once again the checklist below should give some indication as to whether or not treatment would be beneficial.

Indications of severe visual problems (which are often particularly noticeable in the young).

Eyes are watery under bright light Suffers from headaches/migraine
Looks at things with short quick glances Looks 'through' people
Squints periodically Has bouts of blinking
Uses peripheral vision Finds eye contact difficult
Seems startled when approached Is slow to recognize people at a distance
Does not seem 'in touch' with own body Misinterprets facial expressions
Has dilated or narrowed pupils Opens eyes wide/stares when looking
Attracted to light sources; stares at the sun Rubs, pokes or hits eyes
Shields one eye with hand
Enjoys doing intricate work i.e. tapestry etc.
Looks at feet when walking
Afraid of/has difficulty with heights i.e. goes downstairs one step at a time, has problems using escalators etc. May stumble/fall when stepping from one surface to another.
Doesn't appear to look where going Bumps into things
Enjoys OR avoids:
being in the dark bright sunshine/lights
going through tunnels going through an avenue of trees
night driving
Is fascinated with OR dislikes:-
shadows, reflections certain colours, stripes/patterns
Is very adept/has difficulty:-
picking things up catching a ball
putting a peg/object in a slot/hole (especially if the hole is black)
Has difficulty colouring within lines
Creates extremely intricate designs
When writing:-
has problems when copying (better with large print)
uses large letters; runs words together
stops frequently/becomes tired quickly shuts or rubs eyes
When reading:-
misreads or combines words repeats words/lines
skips words/lines
Has difficulty in distinguishing letters/words on a blackboard/whiteboard or on a page
Hyperlexia

Currently only a few organizations are able to carry out relevant tests and offer tinted lenses.
One is the Irlen Institute. While those able to respond accurately are easy to assess for tints the Irlen Institute, like myself, are also working on testing people who are unable to co-operate; which is obviously more difficult and time consuming.

Treatment for such visual perceptual problems is now also available from the Institute of Optometry in London (using a machine called a Colorimeter) although this is more suitable for people who can communicate accurately.

The benefits of tinted lenses.
Results are obviously dependent on the initial problems but those treated suggest they include:
· better eye tracking: better depth perception.
· less confusion, improved behaviour.
· increased confidence, sociability and communication.
· improvements in the ability to listen, concentrate and learn.
· better memory and understanding.
· reduced hyperactivity
· increased ability to hold thoughts and to conceptualise.

NB The wrong lenses will, at best, have no effect and, at worst, could cause physical problems
(headaches/migraine) or even behavioural problems.

Conclusion
While the importance of factors such as diet are increasingly acknowledged the significance of the sensory problems is often overlooked. Surely it is time to listen to the accounts of the people who live with such problems every day. To take them seriously. Some do have sensory problems which cause great stress and distress. Detailed investigation is needed to accurately gauge the number of children and adults who are affected by such sensory problems and enable any necessary treatment to be given.

Reading List
· Bérard, G. (1993) Hearing Equals Behaviour. Keats Publishing.
· Gerland, G. and Tate, J. (trans) (1997) A Real Person life on the outside. London Souvenir Press.
· Gillingham, G. (1991) Autism: Disability or Superability. Sunderland: Collected papers: THERAPEUTIC APPROACHES TO AUTISM: RESEARCH AND PRACTISE.
· Irlen, H. (1991) Reading by the Colors. New York: Avery Publishing Group.
· Jordan, I. (1998) Visual Dyslexia. Desktop Publications.
· Stehli, A. (1990) The Sound of a Miracle. USA: Doubleday.
· Stehli, A. (ed) (1995) Dancing in the Rain. USA: The Georgiana Organization Inc.
· Volkmar, F. and Cohen, D.J. (1985)The Experience of Infantile Autism: A First Person Account by Tony W. (1985) Journal of Autism and Developmental Disorders. 15,1,45-54.
· Waterhouse, S. (1999) A Positive Approach to Autism. London: Jessica Kingsley Publishers.
· White, B.B. and M.S. (1987) Autism from the Inside. Medical Hypotheses 24.
· Wilkins, A. (1995) Visual Stress. Oxford Science Publications.
· Williams, D. (1998) Like Color to the Blind. London: Jessica Kingsley Publishers.

Stella Waterhouse is the author of A Positive Approach To Autism 2000 Jessica Kingsley Publishers:London. She also offer Auditory Training to people with autism, Asperger's syndrome and related disorders.