The term “stimming” is short for self-stimulation (also called stereotypy) and refers to repetitive movements. These types of behaviors are currently listed in the Diagnostic and Statistical Manual as one of the symptoms of autism: “stereptyped and repetitive motor mannerisms (e.g. hand or finger flapping or twisting or complex whole-body movements.”  In children with autism, some common stimming behaviors include:
- Hand flapping
- Snapping fingers
- Turning in circles
- Vocalizing parts of video or television scripts
- Ripping or shredding items
- Making vocal noises or repeating a word or phrase over and over
- Moving fingers in front of eyes
- Staring repetitively at a light
- Rubbing the skin or clothing
- Rocking from side to side
- Spinning toys
It is important to realize that many young children without autism exhibit these types of behaviors. According to John Hopkins Medicine suggests that as many as two-thirds of infants exhibit some type of motor stereotypy, such as thumb sucking or body rocking.  Many stimming behaviors continue throughout a person’s life, for example twirling your hair or biting your nails.
Causes of Stimming
Both typical and autistic stimming behaviors may be used to help regulate sensory stimulation and to relieve anxiety. However, stimming behaviors in children with autism is often out of the realm of normal behaviors, such as toe walking or licking objects.
Medical experts aren’t sure and don’t all agree why stimming is common in children with autism. Some believe that these behaviors are used to block out overwhelming sensory input, others believe stimming is a way of relieving anxiety and some experts believe it may be used to get attention. It is quite possible that stimming is used for many different reasons.
Managing Stimming Behaviors
While some stimming behaviors are harmless and do not need any intervention, other times, these behaviors may cause problems. If a child uses behaviors such as head banging or scratching so intensely as to cause bodily harm, parents and doctors need to find a way to help control these behaviors. Other stimming behaviors may simply be difficult for caregivers. For example, if you are trying to talk to your child and he stands in front of you repeating a word over and over, communication is even more difficult. In these cases, parents may want to find ways to help control stimming behaviors.
Some ways to manage stimming behaviors:
- Provide a more socially-appropriate behavior as a substitute. Dr. Stephen Edelson gives the example of chewing on a rubber tube rather than biting one’s arm. 
- Observe your child to see if the stimming serves a specific purpose. For example, does your child have these behaviors during times of high stress? If so, work on finding ways to manage the underlying cause – in our example, create strategies and seek treatment for anxiety.
- Decide which behaviors need to be changed. Some stimming behaviors may be unobtrusive and can be left alone. As you observe your child, think about which behaviors should be immediately addressed and which ones can be ignored.
- Use verbal reminders when your child is involved in stimming behaviors.
- Talk with your child’s Occupational Therapist about ways to regulate sensory input (by either increasing or reducing sensory stimulation).
- Provide positive reinforcement for not engaging in the behavior. You may want to tell your child he can play with a favorite toy if he does not flap his hands for a set amount of time. Start with a very short time and slowly increase the time as your child succeeds.
- Talk to your child about the behavior, explain why the behavior is not acceptable or that it is not acceptable in certain situations. You may want to videotape your child and let them see what the undesired behavior is. Talk about what behaviors would be more acceptable.
In some cases, medication can help. If behavioral strategies don’t seem to be helping, talk with your child’s doctor about what else you can do.
 “Autism Spectrum Disorders,” 1994, Diagnostic and Statistical Manual, American Psychiatric Association
 “Frequently Asked Questions,” Date Unknown, Staff Writer, John Hopkins Health System
 Self-Stimulatory Behavior (Stimming),” Date Unknown, Stephen M. Edelson, Ph.D., Autism-Help.org
“Stimming: Repetitive, Stereotyped and Sometimes Self-Injurious Behaviors,” Updated 2008, Oct 30, Staff Writer, Interactive Autism Network
“Treating and Addressing Stereotypy,” 2002, Bridget Taylor, Psy.D., BCBA, Association for Science in Autism Treatment