One of the hallmark features of Autism Spectrum Disorder (ASD) is the demonstration of stereotyped behavior. Within the realm of Autism, stereotyped behavior typically refers to actions that are either repetitive, odd (not related to situation), or overly ritualistic/routined. This can apply to both movement and speech and can be very disruptive for both the person with ASD as well as the other people involved in the interaction. Some people refer to these as self stimulatory behaviorn or 'stimming' for short. What is unique about this behavior is that it difficult to find an external stimulus (trigger) for the behavior and even more difficult to stop or re-direct the behavior once it starts. Applied Behavior Analysis (ABA) teaches us that all behavior serves a function or purpose. Spech/Language Pathologists (SLP's) similarly assert that all behavior is a form of communication. If that is the case then what is the purpose or message behind sterotyped behavior?
The answer to this question may lie in another aspect of ASD, which is now included in the diagnostic criteria for Autism Spectrum Disorder in DSM 5. Sensory regulation refers to the body's ability to organize and filter all of the information we receive through our senses. This includes everything that we see, hear, feel, smell, and taste, along with our ability to process our movement and relation of our bodies to the physical environment. People with ASD are often overly sensitive or not sensitive enough to these stimuli. Examples include:
Vision - May have a sharp eye for visual detail, but may become overly excited in places where there is a lot of visual stimulation (e.g. crowds and larger department stores). There may also be a startle effect in situations where there is sudden and unpreditable movement, such as sporting events.
Hearing - The person may have very sensitive to hearing. You might notice someone with ASD being able to hear a train or plane well before anyone else notices it and there may be a strong affinity or talent for music as well. On the other hand, loud noise may become overwhelming and excessively high or low pitched tones can become quite irritating. I've heard many individuals with ASD complain about the hum from flourescent lights or even the clicking of a computer keyboard or high heel shoes.
Touch - With this sense, individuals with ASD are typically overly sensitive to light and unexpected forms of touch like tapping on the shoulder, light rubbing, and certain types of clothing. Conversely, this same person may be under sensitive to hard forms of touch and pain . Some individuals intentionally try to create a pain response because it feels good to them.
Taste/Smell - Some people may be overly picky eaters or have an excessive aversion to cleaning fluids or other strong smells. The picky eating can also be related to the texture or feel of the food.
Movement - Proprioception refers to a person's ability to perceive themself and their movement in relation to others and the space around them. A disturbance in this area can affect balance and the ability to move quickly and efficiently. It can also affect social skills such as personal space and playing interactively.
The basic relation of sensory dysfunction to stereotyped behavior is that the odd behavior typically comes when the person is either overstimulated or understimulated. Therefore, if the amount of stimulation can be regulated, then there will be less sterotyped behavior. Sensory regulation can be achieved in two ways: Through modifying the immediate environment around then person and by applying sensory regulation techniques to the person. The person can also do both the environmental modification and senosry regulation themselves if able.
Environmental modifications to reduce sensory stimulation include avoiding places of high stimulation such as crowded restaurants, parties, or department stores. When playing music, be sure sure it is not too loud, high pitched, or have an excessive bass tone. When out in public always look for the quieter less crowded areas. Sometimes you can't help being in a highly stimulating environment. When that is the case, plan periodic breaks to a quieter area to allow for relief from the stimulus overload. Also, when you see someone becoming more restless or irritable, this would be a good time for a break thus preventing a potential meltdown.
There are also several simple techniques people can use to promote sensory calming during times of distress. Psychologists often recommend taking several slow deep breaths. The increase in oxygen provides the energy needed for impulse control and the slow rhythm of the breath activates the parasympathetic nervous system which slows the body down. Additionally, Occupational Therapists recommend applying deep pressure to the joints as a way of releasing endorphins and providing physical stress relief. Deep pressure can be achieved in several simple ways including chewing, squeezing a small ball, exercise, running, jumping, and swimming. Swimming is especially good because it combines exercise with water which is heavy and applies further pressure. Firm pressure and weight can also be gained through wearing heavy clothing or deep massage. If a person with ASD allows a hug, it is typically a deep hug.
Conversely, stereotyped behavior can also occur as a function of seeking stimulation. This often happens when there is a lack of interaction or direct activity. Sometimes the answer can be as simple as directing the person to a structured activity of interest. The activity should be specific and within the person's skill set or they may revert back to the stereotyped behavior because it is more stimulating or less difficult than the activity that is planned for them. In addition, many of the deep pressure activities that promote calming such as chewing and squeezing a ball can also provide a mild stimulating effect, which can be helpful when the person has to pay attention and concentrate.
Therefore, I recommend that sensory regulation be part of every behavior treatment plan for people with ASD. Once sensory regulation can be achieved, the the person's extra sensitive senses can be used as a strength and not a weakness. Sensory regulation will also help the person with ASD be in a better physical and emotional state to receive education and training in new skills and adaptive behavior.