What is Stereotyped Movement Disorder?

Table of Contents

Last Updated on March 14, 2023 by Mike Robinson

Stereotyped movement disorder is a disorder that appears in childhood and adolescence in which the person makes movements of a peculiar nature that interfere with the life of the person and affect the personal and social environment.

To make it more straightforward what this disorder consists of, I will give an example of a specific case.

Maria’s body is active when she is excited by something. For example, when watching a movie she likes at home, she often rubs and wriggles her hands when a part of the movie she likes is coming. Sometimes she extends her arms straight in front of her and draws on her face in a happy grin, eyes wide open, full of happiness.

You can wring your hands, extend your fingers, and grin dozens of times while watching the movie. But when someone asks what he is doing, he usually stops immediately. At school or in other environments where she is less relaxed and more aware of the reactions of others, she rarely rubs her hands or grimaces.

The definition that best fits what it implies is that of Sambraus, which defines them as repetitive movements that seem impulsive, have a rhythmic character and lack an objective and purpose to which to go. They are individual and are presented temporarily, with a transient or persistent variation.

However, the definition of stereotypies is more complex than it seems, as it can be confused with other movement disorders.

Stereotypes in Humans

It is important to remember that non-pathological stereotypes can occur for various reasons, such as mimicry, and social isolation, when there are no stimuli in the environment, when the person is frustrated, and when excitement or joy occurs.

Many of these behaviors appear at specific moments of development; for example when the child reaches a new milestone in their development, such as learning to walk or saying their first word. These immature behaviors represent a step towards mature behavior. Still, when they last for a considerable time and acquire a pathological function, we speak of a greater degree of severity that affects the individual and produces discomfort.

Stereotypes may be present in various pathological disorders, such as pervasive developmental disorders such as autism, Asperger syndrome, a disintegrative disorder in childhood, and Rett syndrome. However, reference disorder is the disorder of stereotyped movements.

Causes of Stereotyped Movement Disorder

As for the theories that have tried to explain the subject, we can refer to a biological theory in which self-injurious and stereotyped behaviors are the consequences of physical factors, typical or altered.

And to behavioral theory, behaviors are classes of operated responses maintained by reinforcement. That is, the stereotypical behavior may indicate the presence of something stimulating; that is, the behavior may complement any other action that the subject performs, for example, to relax.

A more complex aspect to understand is that self-harm behaviors are maintained. Some studies show that these can influence the release of endorphins in the brain (neurotransmitters responsible for pleasant sensations).

Classification of Stereotyped Movement Disorder

The disorder of stereotyped movements has different categories according to the reference manuals that we handle: CIE, DSM-IV-TR, and DSM-5.

According to the International Classification of Diseases (CIE), stereotyped movement disorder is a behavior disorder and an emotional disorder of habitual onset in childhood and adolescence under the name “stereotyped motor disorders. The diagnostic criteria in the ICD are stricter since the diagnosis of this disorder can not occur in the presence of any other disorder except mental retardation. Another differential characteristic is that it requires one month of the presence of stereotyped movements to diagnose the disorder.

Concerning the Manual for the Diagnosis of Mental Illness, its Fourth Edition (DSM-IV) places stereotyped movement disorder within the category of disorders normally diagnosed for the first time in childhood and adolescence, among others.

Finally, the Diagnostic Manual of Mental Illnesses, in its most recent version (since it came out in 2014), Version 5, makes a meaningful change as it goes on to name the disorders with onset in childhood, adolescence, or late childhood as disorders of neurodevelopment. And in this case, the disorder of stereotyped movements is placed in a broad category called motor disorders,” along with others such as tic disorders and developmental disorder coordination.

Diagnostic categories of the DSM-5

For the categories proposed by the DSM-5 to diagnose stereotyped movement disorders, we find the following:

A criterion. Repetitive motor behavior, apparently guided and aimless (e.g., shaking hands, rocking the body, hitting the head, beating your own body).

Criteria B: Repetitive motor behavior interferes with social, academic, or other activities and can lead to self-harm.

Criterion C. begins in the first phases of the development period.

Criteria D: Repetitive motor behavior can not be attributed to the physiological effects of a substance or neurological condition and is not due to another neurological or mental developmental disorder (e.g., trichotillomania or obsessive-compulsive disorder).

The DSM proposes that it will be necessary to specify if it occurs with self-injurious behavior or behavior that would lead to injury without preventive measures.

It must also be specified if it is associated with a medical or genetic condition, a neurodevelopmental disorder, or an environmental factor known as, for example, Lesh-Nyhan syndrome, intellectual disability, or intrauterine alcohol exposure.

Finally, the DSM-5 adds a new dimension regarding gravity. Therefore, it is acceptable to classify this disorder as mild, moderate, or severe.

Mild: if symptoms disappear quickly with sensory stimulation or distraction.
Moderate: If symptoms require explicit protection measures and behavior modification,
Serious: continuous monitoring and protective measures are necessary to prevent serious injuries.

Self-injurious behavior varies in severity in different dimensions, such as frequency, impact on adaptive functioning, and the severity of bodily injuries (from mild bruising due to hand blows against the body through finger amputation to retinal detachment). Blows to the head

Remember that these stereotyped movements may indicate an undetected neurodevelopmental problem, especially in children aged 1 to 2 years.

Additional Diagnostic Characteristics

The disorder of stereotyped movements, with or without self-injury, occurs in all races and cultures. In many cases, the presence of unusual behaviors is more typical, which can lead to a delayed diagnosis.

Stereotypical movements are often rhythmic movements of the head, hands, or body without apparent adaptive function. These movements may or may not stop. It is more complicated in children with neurodevelopmental disorders than they can control these movements. Children sometimes use strategies such as sitting on their hands, wrapping their arms in their clothes, or finding a protective object.

In children with typical development, the movements can stop when the child pays attention to the movement or something distracts the

This varied repertoire of movements is particular to each individual. Here are some examples.

As for non-self-injurious stereotyped movements, they include: rocking the body; fluttering or rotating movements of the hands; rapid movements of the fingers in front of the face; shaking or flapping the arms, as if they were birds; and affirmative actions with the head.

Concerning self-injurious stereotyped movements, these can be: repetitive blows to the head; slapping the face; biting the hands, lips, or other parts of the body; and sticking your fingers in the eye, which is particularly worrying because it also usually occurs in children with a visual deficiency. You can combine many movements, such as tilting the head, rocking the torso, or repeatedly shaking a string in front of the face.

Regarding frequency and duration, the DSM specifies that they can occur many times during the day or spend several weeks between episodes. They can also last from a few seconds to several minutes.

The context in which they occur is also fundamental since they tend to happen, especially when the individual involves himself in other activities with all the attention placed on them or when he is excited by some event, stressed, fatigued, or bored.

Prevalence and Development

Concerning the prevalence of the disorder, you must consider whether they are simple or complex stereotyped movements.

The simple ones occur in organic brain disorders such as cortical atrophy and arteriosclerosis and have a stimulating function. For example, they are movements like scratching, rubbing, or clapping. These movements are frequent in young children with typical development and may be involved in acquiring motor control.

The complexes occur in psychiatric disorders and are striking and bulky movements of hands and arms (touching and playing with objects and hair). For example, the rituals of obsessive-compulsive disorder are stereotypical. These movements occur in 3–4% of the population. In addition, between 4 and 16% of the subjects with intellectual disabilities present stereotypes and self-injurious behaviors.

Studies find that headbutts are more prevalent in men and self-injuries in women.

Regarding the beginning of the disorder, we know that it usually appears in the first three years of life. For children with complex motor stereotypes, approximately 80% show symptoms before two years, 12% between 2 and 3 years, and 8% at three years or later. The movements reach their maximum in adolescence, and from then on, they can decline gradually.

In most children, these movements reach an early resolution or become less evident. However, in individuals with intellectual disabilities, stereotyped and self-injurious behaviors may persist for years, although the typography or the pattern of self-harm may change.

Risk Factors and Prognosis

Among this disorder’s risk factors and prognosis are those related to the environment and those genetic or physiological.

Regarding environmental issues, several studies have agreed that social isolation is a risk factor for self-stimulation. This can lead to stereotyped movements with repetitive self-harm in the future. There is also an allusion to environmental stress and fear that may influence the triggering of these.

As for the genetic aspects, low cognitive functioning can generate these movements. That is why they frequently appear in intellectual disabilities such as Down syndrome. However, they are more common in those with moderate, severe, or profound intellectual disabilities. Self-injurious and repetitive behavior can be a behavioral phenotype in neurogenetic syndromes such as Lesh-Nyhan syndrome, characterized by severe self-injuries.

Comorbidity

As I mentioned earlier, stereotypes are a common manifestation of several neurogenetic disorders. The two diseases must be codified when the stereotyped movements coexist with another medical condition.

Conclusion

Although this mental disorder is not as frequent as others in childhood and adolescence, such as tics or learning difficulties, it is essential to pay attention to these subjects, especially if the behaviors can become self-injurious.

Therapeutic interventions of the conducting type, derived from operant conditioning, are a good option. These are for the realization of alternative entertainment activities or others that keep people occupied or reduce stress for those subjected to them by teaching problem-solving techniques.