Self-stimulatory behavior or “stimming” is defined as repetitive movements or vocalizations involving one or more of the individual’s sensory channels. Stimming is very common in individuals with autism and can take many forms; hand flapping, rocking, finger flicking, spinning and lining up objects, the list goes on and on.
I always like to point out that we all engage in self-stimulatory behaviors, especially when we are experiencing emotions such as boredom or excitement. Tapping a pencil on a desk, rocking your leg or foot when sitting, twirling your hair, these are all self-stimulatory behaviors, however, these forms of self-stimulatory behaviors are typically acceptable to society. When individuals with autism engage in self-stimulatory behaviors, they often look unusual, and such behaviors can certainly be stigmatizing. Additionally, even though such behaviors may seem harmless, they can be very detrimental in terms of attentional abilities at home, school, and community settings and can greatly interfere with the learning of new skills.
Experts in the field who have studied self-stimulatory behaviors have hypothesized that there are two primary reasons why individuals with autism engage in these unusual repetitive behaviors. The first theory involves hyposensitivity, that is, the individual’s body craves stimulation. Basically, the self-stimulatory behavior serves to arouse one’s nervous system and provides the individual with some form of internal satisfaction. This is thought to be the result of a dysfunctional system in the brain and/or the nervous system. The second theory involves the opposite function, that is, hypersensitivity. In this theory, self-stimulatory behaviors are not engaged in to excite one’s nervous system, but to calm one self. This could be the result of an environment that is over-stimulating and the individual with autism is experiencing sensory overload, therefore engages in self-stimulatory behaviors not to arouse the nervous system, but to block out the over-stimulating environment.
It might seem logical to simply intervene and try to stop the individual from engaging in the self-stimulatory behavior; however, this strategy is not recommended. Since the individual is engaging in these behaviors for a reason, if we attempt to interrupt and stop the behavior, it is possible that another behavior, that could possibly be more stigmatizing or even harmful, could develop.
If a self-stimulatory behavior interferes with the individual’s ability to pay attention to their environment and participate in important activities, there is a basis for concern. Intervention should involve looking at the sensory channel that is being stimulated and replacing the self-stimulatory behavior with another more socially acceptable behavior that will provide the same type of reinforcement.
Here are some common examples of self-stimulatory behaviors as they relate to sensory channels.
Visual: staring at lights, repetitive blinking, moving fingers in front of the eyes, hand-flapping
Auditory: tapping ears, snapping fingers, unusual vocalizations
Tactile: rubbing the skin with one’s hands or with another object, scratching
Vestibular: rocking front to back, rocking side-to-side
Taste: placing body parts or objects in one’s mouth, licking objects
Smell: smelling objects, sniffing people
|Hyposensitive Child (Under-sensitivity)
||Hypersensitive Child (Over-sensitivity)
|Movement:- The under-sensitive child seeks out movement by running backwards and forwards
- Seeks sensory input
|Movement:- The child who screams and refuses to go in an elevator may be over-sensitive to movement. Their behavior reflects their strong desire to avoid movement
|Touch:- The under-sensitive child may become upset when you hug them
||Touch: - The over-sensitive child may lean against another person
|Vision: - The under-sensitive child may seek sensory input by wiggling his fingers quickly in front of his eyes, flicking the lights on and off, looking at objects from an unusual angle, and watching repeated movements.
||Vision:- the over-sensitive child may dislike lights and turn them off
|Smell:- The under-sensitive child may do odd things such as smelling others.
||Smell:- The over-sensitive child may be sensitive to strong smells such as cleaning products or perfume.
|Taste:- The under-sensitive child may like spicy and salty foods. Parents report their over-sensitive children enjoy strong yeast products such as marmite.
- The child may lick objects.
|Taste:The over-sensitive child may be very fussy about food and show a preference for foods with uncomplicated taste. The child may only eat foods that can be presented separately on the plate and refuse to eat dishes that combine vegetables and meat.
If self stimulatory behaviors are interfering with your child’s performance, the following tips might prove to be helpful.
- The first step to reducing a self-stimulatory behavior is to identify what internal or external variable trigger the behavior and determine when and where the behavior is likely to occur. Once the precursor is identified, we can teach the individual an alternative behavior to cope with that situation.
- Replacement Behaviors. Finding acceptable replacement behaviors that are more socially acceptable will provide your child with an alternative to the self stimulatory behavior and receive the sensory input desired. For example, the individual who likes to jump up and down can have trampoline time. The individual who likes to hand flap can hold a squishy toy, the individual who chews their shirt and licks objects can be provided with a chew tube or the individual who always hums can listen to music.
- Both alerting and calming activities can provide socially acceptable alternatives to help reduce self-stimulatory behaviors. Alerting and calming activities can support individuals with autism to learn and interact by helping them stay focused, calm and organized.
- Individuals who engage in sensory-seeking self-stimulation such as spinning, jumping, etc. can be offered a couple of sensory-based items, such as a squishy ball and Theraputty. Present the individual with one of the items each hour and keep track of the number of self stimulatory behaviors that occur in the following 30 minutes. If the self-stimulatory behaviors decrease, incorporate the sensory items into the daily schedule to help decrease self-stimulatory behaviors.
- Permit the individual to engage in self-stimulation for a pre-specified period of time as part of his or her daily schedule. For example, it may be calming for your child to engage in self-stimulatory behavior for the first 10 minutes after arriving back home from school.
- Reduce the amount of stress the individual experiences in all environments. Research shows that self-stimulatory behaviors are more likely to occur following circumstances that are stressful. Attempt to determine what situations are stressful for the individual, and structure the environment in a manner that will reduce stress.
- Consult an Occupational Therapist to help you develop a sensory diet to address the individual’s need for stimulation. Introducing a sensory diet that involves both calming and alerting activities may help reduce self-stimulatory behaviors. This is not a “diet” related to foods you should serve, but rather it involves an activity plan, designed specifically for your individual child, that provides the sensory input your child needs to be focused and organized.
It is important to remember that even after a successful behavior reduction program, many individuals may return to their old self-stimulatory behaviors in demanding conditions. Addressing self-stimulatory behaviors and trying to find appropriate replacements will improve the quality of life for individuals with autism. A reduction in self-stimulatory behaviors will afford individuals with autism greater opportunity to learn new skills without distraction, interact with others without fear of being stigmatized, and in the end, lead more productive and satisfying lives.