1. What causes motor stereotypies in normally developing children?
It is unclear what causes repetitive movements in children who are otherwise normal. Recent research showed that 25% of subjects had a family history of primary motor stereotypies or other movements, suggesting the possibility of a genetic predisposition. Johns Hopkins is currently conducting a study to identify whether there is a genetic connection. Learn about the study and how your child can be a part of it.
2. How common are stereotypic movements in normally developing children?
Stereotypic movements in children are common, in fact. While exact numbers are unknown, it has been suggested that common motor stereotypies
(e.g., thumb sucking, body rocking, nail biting) may occur in as many as two-thirds of infants and half of children under age 15. Prevalence of complex motor stereotypies
(e.g., hand flapping, arm waving) may be as high as 3 to 4% of U.S. preschool children.
3. When do children usually start these repetitive movements?
Typically motor stereotypic movements begin within the first 3 years of life. In a study
of normal children who exhibited flapping or waving of the arms or hands, 80% began before 24 months of age; 12% between 24 and 35 months; and 8% at 36 months or older.
4. Will these repetitive movements go away?
Whether they go away depends on the type of movement the child is exhibiting. Children who exhibit complex movements
(e.g., hand/arm waving movements) are likely to have persistent symptoms. Some movements may stop or slow down or become less severe over time. It has been falsely suggested that complex motor stereotypy disorder is a brief problem that will simply just go away after a short period of time. More research is needed in this area, but one longitudinal study
followed 100 children for several years and found that only 3-5% stopped or were otherwise completely resolved.
5. Are there situations that can make the stereotypies worse or more frequent?
These movements often appear or increase in frequency when a child is stressed, fatigued, anxious, excited or engrossed in an activity.
6. If not treated, will primary motor stereotypies turn into something else, like autism?
No. The movements themselves do not indicate whether a child is normal or has other problems. In children with primary stereotypies, a small percentage may develop associated problems such as tics, attention-deficit/hyperactivity disorder (ADHD) or obsessive-compulsive disorder (OCD).
7. Does diet play a role?
There is no scientific evidence that the addition or omission of certain foods (or vitamins) has any benefit. The only treatment for primary motor stereotypies that has proven to be successful is behavioral therapy
8. What is the difference between motor stereotypies and tics?
These disorders are often mistaken for each other, but there are several characteristics that may help differentiate the two.
- Stereotypies have an earlier age of onset (usually before 3 years), while tics have an average onset of 5-7 years of age.
- Stereotypies are consistent and fixed in their pattern, whereas tics evolve over time.
- Stereotypies frequently involve the arms, hands or entire body. Tics are more commonly seen in the eyes, face, head and shoulders.
- Stereotypies are more rhythmic and prolonged in duration.
- Stereotypies quickly stop/cease with distraction.
9. My daughter is getting ready to start school. Will she have trouble socializing or focusing in class?
Most movements do not negatively impact a child’s daily routine. We see many children with stereotypies, and most do really well despite parents' concerns about school. If movements are frequent, it helps to inform the school's teachers so they have a better understanding of the disorder and know what to expect.
10. I read that behavioral therapy only works for children age 7 and up. What can I do for my 3 year old?
Today the most effective treatment is behavioral therapy
, which requires active participation by the child. This treatment is only effective in children who are old enough to understand the instructions of a behavioral therapist. We’re currently conducting clinical studies
with the goal of developing a treatment for all children. Until then, our approach is to educate the family and help them to understand that primary motor stereotypies are completely harmless and are unlikely to negatively impact their child’s daily home, school or social life.
11. My child has started showing signs of motor stereotypies—what should I do?
If a child is showing signs and symptoms of motor stereotypies
, parents should discuss their concerns with a pediatrician or family doctor, who will refer the child to a pediatric neurologist for further evaluation if necessary.
12. I’ve noticed that my son stops flapping his arms if I distract him by saying his name. Should I keep doing this?
Motor stereotypies cease with distraction, but we strongly advise that this type of awareness training should be conducted as part of formal behavioral treatment program. When a child is frequently alerted of his movements outside of a formal therapy setting, there is a concern that it could lead to psychosocial problems. The best approach is to pursue formal treatment with a behavioral therapist.