Repetitive and stereotyped behaviors (RSB) are considered a core symptom of autism spectrum disorders (ASD). This defining symptom has been known since the original series of 11 children described by Kanner. Some of the repetitive behaviors exhibited by these children included jumping, spinning and other rhythmic body movements. Longitudinal studies using either retrospective parental interviews and/or systematic observation reveal that RSB in autistic children unfold with aging, becoming increasingly prevalent between 3 to 5 years of age. The quantity and severity of RSB are directly related to negative outcomes and appear to be co-dependent with social and communication symptoms.
Some people believe that repetitive behaviors like hand-flapping may benefit the child as they may serve as a way of coping with frustrations (e.g., when the environment becomes unpredictable) or a way of communicating. A Neurodiversity proponent, Ms. Julia Bascom, has gone so far as to state that they are a part of her personality, “Is flapping my hands or intensely and obsessively loving something ‘weird’ or wanting to be myself the psychological equivalent of diabetes, or is it a natural and beautiful part of human diversity/” (http://www.thedailybeast.com/articles/2015/02/25/they-don-t-want-an-autism-cure.html).
Contrary to Ms. Bascom’s statement people with obsessive-compulsive disorders are unable to control their thoughts and/or activities. Patients often fall into a spiral of thoughts and actions that gets hardwired into their brain. You can wash your hands until they become raw and the skin ulcerated or your repetitions are so time-consuming as to become disabling. In some cases repetitive behaviors, such as head banging, may give rise to brain damage or death. Bruxism or teeth grinding, is a motor movement disorder or RSB that may lead to dental fractures and wearing down of the tooth enamel. Attrition of the teeth may necessitate placement of steel crowns under general anesthesia. In one ASD study bruxism was reported to occur in approximately one-fifth of surveyed children (Williams et al, 2004).
In the case of my grandson Bertrand his obsession was spinning objects. This materialized probably by his third year of life. Bertrand did not appear to be upset prior to or while spinning objects. His behavior was similar to that of an addict where triggers from the environment (e.g. in the case of an alcoholic the trigger could be passing by a bar) prompted the ritualistic behavior. Anything that could spin looked to Bertrand like a wheel. Once engaged nothing would draw him out of the same.
Contrary to the opinion of Neurodiversity proponents repetitive behaviors are not a social lubricant. Some of these repetitive behaviors, just as in an addiction, hijack your brain and make you numb to other activities, or at least they become less pleasurable. The more you perform them the harder it is to quit. In time, performing the repetitive behavior is the only thing that makes an individual feel well.
The prefrontal cortex controls the urges stemming from subcortical centers. Failure of this executive center to inhibit other areas of the brain may lead to problems in impulse control including tantrums or maladaptive behaviors. Indeed many times maladaptive behaviors coalesce and frequently manifest as a number of behaviors rather than single exemplars. In autism the prefrontal lobes appear to be affected thus providing vulnerability to repetitive behaviors as well as for faulty programming of planned sequences or theory of mind. Also, similar to an addiction, certain alterations in risk genes for autism (e.g., DRD2) are found as an inheritable component of addictive behaviors (Hettinger et al., 2012).
The available data makes us believe that although anxiety may play a role in some cases of RSB, in others it may be a manifestation of an addictive behavior. It also makes us wonder whether fixation in certain interests, like playing video games, may all stem from the same causative mechanism.
Hettinger JA, Liu X, Hudson L, et al. DRD2 and PPP1R1B (DARPP-32) polymorphisms independently confer increased risk for autism spectrum disorders and additively predict affected status in male-only affected sib-pair families. Behav Brain Funct 8:19, 2012.
Williams GP, Sears LL, Allard A. Sleep problems in children with autism. J Sleep Res 13:265-8, 2004.