Sensory vulnerabilities in autism spectrum disorder

SOME PEOPLE have difficulties in organising information from the senses. These include responding to sights, sounds, smells, touch and sensory input related to balance and movement.

Many persons associate children on the autism spectrum with unusual actions, such as covering their ears especially when they are in a physical space with other persons, constantly moving about, making noise just for noise’s sake, and of course there is often a big problem with eating a variety of foods. My first contact with a young child who was on the autism spectrum over 30 years ago was her refusal to have anything to eat except for orange juice and bacon. She could not be cajoled to have any other food and if any attempt was made to put any supplements in the orange juice, she would immediately detect the difference in the smell, no matter how minute the amount added. She was a well-developed, healthy-looking child but her parents were really concerned about her eating habits, and rightly so. This young child is now an adult and she seemed to have survived that period of her life.

SENSORY INTEGRATION DYSFUNCTION

The fact is that autism spectrum disorder has an associated diagnosis of sensory integration dysfunction which is recognised by the Diagnostic Statistical Manual (DSM) of Mental Disorders. The processing of sensory information by the brain is necessary for performance and participation in activities of daily living. As an occupational therapist this link was apparent from my early days of practice since my role was to find ways to have children engage in activities of daily living in a meaningful way. The sensory system informs the body how to respond to what it is experiencing, therefore, if the food has a particular taste, smell, texture or even looks like something to avoid, the child will not eat it. Parents often report that the child will gag on the food if they try to get them to swallow it. There is also sensory information that informs about balance and movement. These experiences are real not imagined. This is a processing and interpretation problem which is occurring in the brain.

Sometimes there is a delay in the response, that is, in the processing of information since the signals are not properly received and interpreted by the brain. This is observed when the child on the autism spectrum does not respond immediately to instructions or even to his name. However, the child is sometimes heard repeating (rehearsing) what he heard earlier.

The child who covers his ears is blocking out the sounds that are really painful to him as he has a hypersensitive response to what others would find tolerable. He or she becomes really agitated in a crowded, noisy environment since the difficulty may now be in processing multiple sensory information that is happening around him at the same time and it is overwhelming. A trip to a mall is usually exciting for a child at Christmas time, but for the child on the autism spectrum this might be a nightmare – too many sounds, lights, people. Exposure to experiences such as a trip to the supermarket or to church must be gradual with considerations given to the time of the day, preferably when there are fewer persons shopping, and where they sit in church as a family all matters. Seating around the periphery of the worshippers away from the intensity of the crowd and the singing with music might be a more comfortable experience for the whole family.

SENSORY OVERLOAD

It is hard to imagine that a child might find a birthday party overwhelming or a painful experience, but it is not unusual for the child on the autism spectrum to experience sensory overload and retreat to a quiet space if he can find one. This child could be seen as antisocial or at the other extreme end, to be aggressive because he cannot readily modulate his actions in this physical space. This simply means he does not have the ability to know when and how to control his behaviours. Instead of retreating, the child on the autism spectrum could become overly excited and demonstrate this overload by being physical with excessive movement, disorientated, and cannot navigate his way in this overly stimulating space where everyone is having ‘fun’.

It is important to point out that dysfunction of the sensory system of the body does not only occur in persons on the autism spectrum. This can be a separate diagnosis so that there are many persons who can attest to the fact that even as adults they are over sensitive to touch, cannot work with sticky substances, or wear clothes that are made out of certain material or annoyed by tags on their clothes. Some of us as adults are hypersensitive to sounds. The point is that these things are annoying, but they should not interfere with our performance of our daily function. If you find you are going out of your way to avoid a sensory experience, you could possibly have a sensory dysfunction.

The good news is that much can be done through different interventions to assist children on the autism spectrum or adults living with sensory integration dysfunction to overcome what can be a debilitating disorder. The occupational therapist will guide towards a gradual building of tolerance for a particular experience or a possible sensory diet which allows the brain to accommodate this experience as something positive. At home, parents will find that if they are patient and are incremental in their approach, that is, only give small bits of exposure to what the child is avoiding such as food. For birthday parties, start with small play dates before introducing birthday parties. The brain can and will, over time, accommodate and modulate multisensory experience at a level that is within normal limits.

Dr Pauline Watson Campbell is a paediatric occupational therapist and educational psychologist. She is also author of Sealing the Cracks: Managing Behavioural Problems in the Classroom. Email feedback to: editorial@gleanerjm.com.