Autism - Description & Approaches

What is Autism? ››

What Causes Autism? ››

The History of Autism ››

The Triad of Impairments ››

The Continuum ››

Sensory Issues

Approaches ››

Sensory Issues
Introduction to Sensory Processing Concepts
Sensory processing is a complex set of actions that enable the brain to understand what is going on both inside your own body and in the world around you.

To function and participate in the world that surrounds us, we need to use our senses. Senses provide individuals with unique experiences and allow us to interact and be involved with the rest of society. They help us to understand the environment around us and respond within it.

They play a significant role in determining what actions we take within a particular situation. Imagine what happens when just one or all of your senses are intensified or are not present at all, often referred to as sensory integration dysfunction. This is the case for many individuals on the autistic spectrum.

There are several definitions of autism but they rarely state what an autistic individual feels. It is only through personal accounts from individuals themselves who can express and describe their unique and often painful sensory world that we find out more. Everyday functions, which the majority of individuals take for granted, can for autistic individuals be negative and upsetting experiences. Behaviours presented by someone with autism will often be a direct reaction to their sensory experience. It is therefore understandable why they create rituals, or have self-stimulatory behaviours such as spinning, flapping and tapping, because this makes them feel they are in control and feel safe in their unique world.

Sensory Issues
Stimuli from both inside and outside our bodies sends information to our senses. This information from our senses allows us to function in the everyday world (Kranowitz, 1998). Smell, touch, hearing, sight and taste are the five senses that respond to stimuli from outside our bodies. Three other important sensory systems are the tactile, vestibular and proprioceptive systems. The tactile sensory system processes information about touch; the vestibular processes balance, movement and gravity information; and the proprioceptive sense processes information about the body’s position in space.
 
Sensory Integration
An Approach to Help with Self-Regulation and Skill Development
Sensory integration is a neurological process, which occurs in all of us. It allows us to take in sensory information, sort it, shape it and then use the information to help us interact with our environment with ease and comfort. The theory of sensory integration was developed by occupational therapist Dr. A Jean Ayres based on her research into the neurosciences and related fields. The theory is applied to observable human behaviours.

Our senses can be defined as both overt and hidden. The senses that are most obvious are those of sight, hearing, touch, taste and smell. The hidden senses are those of movement (vestibular) and of body position sense (proprioception). These hidden senses are primitive and very powerful regulators of our nervous system and help to build the foundation for purposeful movement.

The process of sensory integration is complex. First we register a sensory event e.g. I feel something touching me. Then we orient to the sensation. Sensation needs to be at a certain threshold in order to be perceived. Thresholds vary through the day as well as with your emotions and stress levels. Here the brain decides whether to inhibit or facilitate the sensation – this is called modulation. This helps us to determine what sensations to pay attention to and what not to. We could not possibly pay attention to all sensory input. Individuals with autism usually have some modulation difficulties. In such cases, a person is too much aware of certain sensations and not as aware of others and can have difficulty switching attention to different sensations. For example, an individual may focus on the feel of their clothing instead of the sound of a voice.

Next our nervous system interprets the information and determines whether the sensation is harmful. This interpretation is based on previous emotional and language experiences and our memories. If the sensation is perceived as harmful, the nervous system quickly acts to protect our body from harm and responds by going into a “red alert” state. This response is labelled as the fight – flight – fright reaction. Our body responds by fighting to protect itself, running away or becoming very fearful. Many individuals with autism constantly operate in this state of over-alertness, hypervigilance and increased anxiety. Just being in this state, lowers sensory registration thresholds.

Once we have perceived and interpreted the sensation, we then organise a response. Our response cay be either physical, cognitive or emotional. For example, “ I like that touch. It makes me feel safe. I will continue to shake his hand”. The final step in the process is the execution of the physical, cognitive or emotional response. If there is a physical response, adequate motor planning is required – an area that is a concern with most individuals with autism.

Sensory Sensitivity
People with autism may be over or under-sensitive to particular sensory experiences. This can result in avoiding or seeking particular types of sensory experiences.

• Hyper or over-sensitive response: a heightened response to a particular sensory experience, as the sensations are registered too intensely.
• Hypo or under-sensitive response: a dampened response to a particular sensory experience, as the sensations are being registered less intensely than normal.
• Response Fluctuations: The individual’s response to particular sensory experiences may fluctuate from one day to the next. Some days the person may seek out certain sensory experiences, on other days he may avoid that same experience. The way the person behaves in response to sensory experiences can be seen as an indicator of what his nervous system requires.

Smell (olfactory) system
Processed through chemical receptors in the nose this tells us about smells in our immediate environment. Smell is a sense that is often neglected and forgotten about. It is, however, the first sense we rely upon. For an individual on the spectrum difficulties/differences may be:

Hypo

• Some individuals have no sense of smell and fail to notice extreme odours.
• They may lick things.

Hyper

• Smells can be intensified and over powering
• Toileting problems
• Dislike of individuals with distinctive perfumes, shampoos. 

Sight (visual) system
Situated in the retina of the eye and activated by light. Our sight helps us to define objects, people, colours, contrast and spatial boundaries. For an individual on the spectrum difficulties/differences may be:

Hypo

• May see things darker, lose features, lines.
• For some they may concentrate on peripheral vision because their central vision is blurred. Others say that a main object is magnified and things on the periphery become blurred
• Poor depth perception - problems with throwing and catching, clumsiness

Hyper

• Distorted vision occurs, and objects and bright lights can jump around
• Fragmentation of images, as a consequence of too many sources
• Focusing on particular detail (sand grains) more pleasurable than looking at something as a whole.

Hearing (auditory) system
Situated in the inner ear, this informs us about sounds in the environment. It is the most commonly recognised aspect of sensory impairment. For an individual on the spectrum, difficulties/differences may be:

Hypo

• Sounds may only be heard with one ear, the other ear either only having partial hearing or none at all.
• The person may not acknowledge particular sounds.
• Enjoys crowded noisy places, kitchens, bangs doors and objects.

Hyper

• Volume of noise can be magnified and surrounding sounds distorted and muddled.
• Inability to cut out particular sounds - difficulties concentrating.
• They may have a lower hearing threshold, which makes them particularly sensitive to auditory stimuli, for example hearing conversations in the distance.
• Their hearing impairment can have a direct effect on their ability to communicate and may also affect their balance.

Taste (gustatory) system
Processed through chemical receptors in the tongue it tells us about different tastes - sweet, sour, bitter, salty and spicy. Individuals will often have restricted diets, as a result of their taste buds being extra sensitive.  For an individual on the spectrum difficulties/differences may be:

Hypo

• Likes very spicy foods
• Eats everything - soil, grass, materials

Hyper

• Some flavours and foods are too strong and overpowering for them.
• Certain textures also cause discomfort. Some  will only eat smooth foods such as mashed potatoes or ice cream.

The Tactile Sense
“The tactile system plays a major part in determining physical, mental, and emotional human behaviour.” (Kranowitz, 1998, p.66)
The tactile system receives information through the receptors in the skin. This very important sense gives us the information that is necessary for us to participate in everyday activities. Inefficient processing of tactile sensations is referred to as tactile dysfunction.

Tactile Hyper or over-sensitivity
Over-sensitivity to certain tactile experiences is often referred to as tactile defensiveness. A person with tactile defensiveness may avoid certain touch sensations, yet may enjoy other touch sensations.
For example, Mary avoids touching certain textures such as shaving cream (light touch), as sometimes this touch may be uncomfortable, or even painful. Mary really enjoys firm ‘bear’ hugs (deep touch pressure) from her dad

Tactile Hypo or under-sensitivity
Under-sensitivity to touch is described as a poor response to tactile stimulation. An under-sensitive person requires more tactile stimulation and often seeks activities that provide this. For example, Jonathon seems to have a decreased reaction to pain as he does not seem to be aware if he touches a hot plate on the cooker, of the burning sensation of hot temperature extremes.

The Vestibular Sense
The vestibular system receives information from the inner ear about the position of our heads and bodies in space. Movement and gravity stimulates the receptors to register every movement we make.
The different types of vestibular movement can have a calming or excitatory effect on the person. Back and forth, side to side, or up and down linear movement, such as a rocking chair, can be calming. Circular movement, such as twirling, excites the vestibular system. Inefficient processing of the information about movement, space, gravity and balance is referred to as vestibular dysfunction.

Vestibular Hyper or over-sensitivity
Over-sensitivity to vestibular movement may result in an excited, emotional or negative reaction to this sensation. A person who is over-sensitive to movement may be intolerant or have a fear of movement (gravitational insecurity). For example, at pre-school David prefers to sit still, rather than playing physically outside. He avoids climbing and playground equipment as he finds the movement to be uncomfortable and sometimes distressing.

Vestibular Hypo or under-sensitivity
A person who is under-sensitive to movement may seek activities that provide vestibular sensations. Usual vestibular activities are not satisfying to this individual who has an increased tolerance for movement. For example, Jane is very active, constantly running from one activity to the next throughout the day. She particularly enjoys vigorous activities, such as climbing and jumping off furniture.  

The Proprioceptive Sense
Proprioception provides us with information about our body position ormovement. This system contributes to body scheme and body awareness, muscle tone and coordinated movement. Proprioception is closely connected with the tactile and vestibular systems. O.T

Poor Proprioception
People with poor proprioception have difficulty interpreting body position and movement sensations. Poor proprioception is usually associated with tactile and/or vestibular difficulties. The person may display poor body awareness, motor control and manipulation difficulties, often perceived by others as “clumsy”.
For example, for sensory feedback Emily uses her oral motor muscles to chew constantly on non-edible objects such as toys, books and her shirt collars.

Hyper

• Difficulties with fine motor skills, manipulating small objects (buttons, tying shoe laces)
• Moves whole body to look at something.
     

Problems, Reasons & Suggestions
Problem: Picky eater
Reason: Sensitive to taste or texture, maybe unable to feel the food around mouth.
Suggestion: Slowly introduce different textures around the individual's mouth –  flannel, toothbrush, foods, introduce small portions, change texture of the food, purée it.

Problem: Chews on everything – clothing and objects
Reason: May find this relaxing, enjoys the tactile input of the item.
Suggestion: atex free tubes, straws, hard gums (chill in fridge).

Problem: Smearing
Reason: May like the texture in their hands or be hypo sensitive to smells.
Suggestion: Try and introduce similar materials –  jelly, cornflour and water.

Refuses to wear certain clothes – dislike the texture, pressure on their skin – turn items inside out – so there is no seam, remove any tags or labels, allow them to wear clothes that they are comfortable in.

Problem: Difficulties getting to sleep
Reason: May have difficulty shutting down senses, in particular visual and auditory.
Suggestion: Use blackout curtains, allow person to listen to music to cut out external sounds, weighted blankets.

Problem: Finds concentrating hard
Reason: May have too many sensory distractions too noisy (talking, chairs scraping the floor), lots of visual stimuli (people, pictures on the wall).
Suggestion: Position them away from the doors and windows, use furniture in the room to create an area free from distraction. 

Dysfunctional Sensory Integration in Autism
Individuals who are hyper- or hypo-responsive to touch, movement, vision, hearing, taste and smell sensations can experience an increased amount of anxiety and a decreased ability to orient, interpret and respond to sensation functionally. This will also affect the ability to self-regulate arousal states. Adequate sensory integration is also necessary for motor planning. Motor planning is our ability to plan, initiate, execute, change and stop motor sequences.

Currently, sensory integration principles are most often applied in the format of a sensory diet. Specific activities are tailored to each individual in a prescribed fashion and applied in a functional manner. Sometimes an individual may benefit from direct treatment approaches, depending on the nature of their difficulties.

A sample sensory diet may include activities containing proprioceptive input. (For the purpose of this article, only examples in this system will be used.) This input can be used as a powerful calming and alerting strategy and can easily be applied into a daily schedule. For example, in self-care routines and fine motor activities, the use of vibration, or weighted cuffs for the wrists can increase body awareness and motor accuracy; use of personal massage units, foot massagers, or shower head massagers during hygiene activities can facilitate calm; the Wilbarger pressure brushing protocol can help decrease sensory defensiveness to clothing; wearing weighted vests, hats, or walking with a heavy knapsack can help during stressful activities or when focus is required. During leisure pursuits, proprioceptive activities could include hiking over rough and steep terrain, horseback riding, clay craft or small carpentry projects. Work related tasks; such as mixing batter by hand, kneading bread, vacuuming or pushing a lawnmower contain proprioceptive elements.

In essence, a sensory diet is much like a nutritional diet and is based on unique individual needs. Use of specific activities can help regulate nervous system alertness to lower anxiety levels, and enhance response and attention to tasks. Application of sensory integration theory is an important part of a holistic approach to help promote selfregulation and motor learning in individuals with autism, thereby increasing functional daily living skills and independence.

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