What do we mean when we say autism is a ‘spectrum disorder?’
When the term, ‘spectrum disorder’ is used it means that there are a range of symptoms, which can be attributed to autism. Any one individual may display any combination of these symptoms, in differing degrees of severity. Therefore an individual at one end of the autistic spectrum may seem very different to an individual at the other end of the spectrum.
Who first discovered autism?
Autism was first recognised in the mid 1940’s by a psychiatrist called Leo Kanner. He described a group of children, whom he was treating, who presented with some very unusual symptoms such as; – atypical social development, irregular development of communication and language, and recurring / repetitive and obsessional behaviour with aversion to novelty and refusal to accept change. His first thoughts were that they were suffering some sort of childhood psychiatric disorder.
At around the same time that Kanner was grappling with the problems of these children, a German scientist, Hans Asperger was caring for a group of children whose behaviour also seemed irregular. Asperger suggested that these children were suffering from what he termed ‘autistic psychopathy.’ These children experienced remarkably similar symptoms to the children described by Kanner, with a single exception. – Their language development was normal! There is still an ongoing debate as to whether autism and Asperger’s syndrome are separable conditions, or whether Asperger’s syndrome is merely a mild form of autism.
What is the cause of autism?
In the 1960s and 1970s there arose a theory that autism was caused by abnormal family relationships. This led on to the ‘refrigerator mother’ theory, which claimed that autism in the child was caused by cold, emotionless mothers! (Bettleheim, 1967). However the weight of evidence quickly put this theory to bed as evidence was found to support the idea that the real cause was to be found in abnormalities in the brain. This evidence was quickly followed by findings, which clearly demonstrated that the EEG’s of children with autism were, in many cases, atypical and the fact that a large proportion of children also suffered from epilepsy.
From this time, autism has been looked upon as a disorder, which develops as a consequence of abnormal brain development. Recently, evidence has shown that in some cases, the abnormal brain development may be caused by specific genes.
However, we should not forget that genes can only express themselves if the appropriate environmental conditions exist for them to do so and so, we should not rule out additional, environmental causes for autism. We should not forget that autism can also be caused by brain-injury, that an insult to the brain can produce the same effects as can abnormal development of the brain, which may have been caused by genetic and other environmental factors. I have seen too many children who have suffered oxygen starvation at birth, who have gone on to display symptoms of autism. So, it is my view that autism can also be caused by brain-injury.
There are also other possibilities, which can ultimately produce the type of brain dysfunction, which we recognise as autism. There is a great deal of research being carried out at the moment in the area of ‘oxidative stress’ and methylation and it’s effects upon the integrity of neural networks. There is also the debate surrounding mercury levels in vaccines, which is as of yet, unresolved.
The fact is that ‘many roads lead to Rome.’ – There are likely to be several factors both genetic and environmental, which can ultimately lead to the type of brain dysfunction, which we call autism.
So, how do we recognise autism?
On a descriptive level, autism involves a dysfunction of the brain’s systems, which control communication, socialisation, imagination and sensory perception. My theory is that it is the distortions of sensory perception, which are so characteristic of autism, which exacerbates many (but not all) of the other difficulties. Imagine a child suffering from autism who suffers distortions of sensory perception. For instance, the child who suffers distortions of visual perception, might find situations which require eye -contact to be exceptionally threatening, or on the other end of the scale might become obsessive about specific visual stimuli. The child who suffers distortions of tactile perception, might at one end of the spectrum find any situation which requires physical contact to be terrifying, whilst at the other end of the spectrum, they might be a ‘sensation seeker’ to the point of becoming self -injurious. The child who suffers distortions of auditory perception might at one end of the spectrum, be terrified of sounds of a certain pitch or intensity, whereas at the other end of the spectrum, they might actively seek out, or become obsessive about certain sounds.
The question is, what can we do to help redress these distortions of sensory perception. Well, we believe we can learn from the newborn baby. When baby is born, he sleeps for most of the time, only spending short periods of time interacting with this new environment in which he finds himself; – a new environment which bombards his senses with new sights, noises and smells. So he retreats into the safe, calm environment of sleep, which provides the sensory safe haven which up until recently was the sanctuary of the womb. Very gradually, as baby adjusts his sensory system to his new environment, he spends more and more time in the waking world, interacting and learning to communicate, – but he adjusts very gradually!
There is possibly a neurological explanation for this. There are structures within the brain, which act to ‘tune’ sensory attention. These three structures, which allow us to tune our attention are structures, which enables us to ‘tune out’ background interference when we wish to selectively attend to something in particular. They also enables us to ‘tune in’ to another stimulus when we are attending to something completely different. They are the same mechanisms of the brain, which allows us to listen to what our friend is saying to us, even when we are standing in the midst of heavy traffic on a busy road. It is these mechanisms that allow us, even though we are in conversation in a crowded room, to hear our name being spoken by someone else across that room. It is these mechanisms, which allow a mother to sleep though various loud, night-time noises such as her husband snoring, or an aeroplane passing overhead and yet the instant her new baby stirs, she is woken. It is a remarkable feature of the human brain and it is the responsibility of three structures operating cooperatively; – these are the ascending reticular activating formation, the thalamus and the limbic system.
Having made such a bold claim, allow me to furnish you with the evidence to support it. The three structures just mentioned receive sensory information from the sense organs and relay the information to specific areas of the cortex. The thalamus in particular is responsible for controlling the general excitability of the cortex (whether that excitability tunes the cortex up to be overexcited, tunes it down to be under excited, or tunes it inwardly to selectively attend to it’s own internal sensory world.) (Carlson, 2007). The performance of these neurological structures, or in the case of our children, their distorted performance seems to be at the root of the sensory problems faced not only by newborn babies, but the sensory difficulties our children face and yes, as the newborn shows, their performance CAN be influenced, – they can be re-tuned.
I believe the sensory system of some children with autism is experiencing similar difficulties to that of a newborn, – at one end of the autistic spectrum, the cortex is being over-excited by these structures and the person is overwhelmed and has difficulty accommodating the mass of sensory stimulation within the environment. At the other end of the autistic spectrum, the cortex is being under-excited and the person has trouble in perceiving sensory stimulation from the environment. The question is; – How do we facilitate the re-tuning of this neurological system in individuals who have autism
The newborn retreats into sleep, a self imposed dampening of incoming sensory information. Whilst the child with autism does not do this, many children with autism attempt to withdraw from their environment because they find it so threatening.
We believe at Snowdrop that for the child at the end of the autistic spectrum who is suffering an amplification of sensory stimulation, we should create a setting where he can retreat from a world, which is overwhelming his immature sensory system. This ‘adapted environment,’ which should be as free as possible from all visual, auditory, tactile and olfactory stimulation will serve as a milieu where his sensory system can re-tune itself. Of course it may just be a single sense like vision, or hearing, or tactility, or any combination of senses, which are causing the difficulties and the environment may be adapted appropriately. The child suffering these difficulties will usually welcome this adapted environment, which is in effect a ‘safe haven’ for his immature sensory system. He should be given free access to, or placed within the adapted environment as needed and you will notice hopefully that he will relax and begin to enjoy being within its safe confines, where there are no sensory surprises.
This procedure should be continued for as long as necessary, – for several weeks or months. Indeed, some children might always need periods of time within the ‘safe haven.’ As the child begins to accept and be at ease in his safe haven, stimulation in whatever sensory modality is causing the difficulties, should begin to be introduced at a very low level, so low in fact that it is hardly noticeable. If the child tolerates this, then it can be used more frequently until it becomes an accepted part of the sensory environment. If the child reacts negatively in any way, then the stimulus is withdrawn and reintroduced at a later date. In this way, we can very gradually begin to build the level of tolerance, which the child has towards the stimulus.
For the child at the other end of the autistic spectrum, the child whose sensory attentional system is not exciting the cortex enough, with the consequence that he is not noticing enough of the stimulation in his sensory environment, the approach needs to be the exact opposite. These are the children who we see producing self-stimulatory behaviour. I believe that this behaviour is an attempt by the nervous system to provide itself with what it needs from the environment, – a sensory message of greater intensity! We see many children with autism ‘flapping’ their hands in front of their eyes, or becoming visually obsessed by certain toys, movements, colours etc. I propose that this is a reaction by the nervous system to attempt to increase the intensity, frequency and duration of the sensory stimulus due to a problem with perceiving visual stimuli from the environment.
Of course, children with autism display a far greater range of difficulties than a theory, focused upon a malfunctioning sensory – attentional system could explain. I am not attempting to claim that sensory problems on their own are an adequate explanation for every facet of autism, – that would be ridiculous! This is merely a possible explanation of a range of issues experienced by some children who have autism, which could be produced or exacerbated by the child suffering distortions of sensory perception. For instance, the following symptoms within the autistic spectrum could possibly be explained at the sensory level.
Failure to make eye contact.
Difficulty in sharing attention with anyone.
Avoiding interaction with others
Avoiding physical contact
Seeming disconnected from the environment.
Appearing not to notice anything visually.
Visual distraction, as though the child is looking at something which you cannot see.
Visual obsession with particular features of the environment.
Inability to ‘switch’ visual attention from one feature of the environment to another.
General discomfort with the visual environment.
Appearing not to hear anything.
Auditory distraction, as though listening to something which you cannot hear.
Auditory obsession with particular sounds within the environment.
Inability to ‘switch’ auditory attention from one sound within the environment to another.
Inability to ‘tune out’ extraneous sounds in the environment.
General discomfort with the auditory environment.
Appearing not to feel much sensation.
Appearing to bee distracted by tactile stimuli of which you are not aware.
Obsession with particular tactile sensations within the environment.
Appears unable to ‘switch’ tactile attention from one sensation to another.
General discomfort with the tactile environment.
Difficulty in communicating with others.
We believe at Snowdrop, that our sensory re-tuning environments offer the best chance for children to overcome such distortions of sensory perception.