Laughter and Happy Demeanor of Angelman Patients

Brian Murphy, Ph.D. avatar

by Brian Murphy, Ph.D. |

Share this article:

Share article via email
laughter in Angelman syndrome

Children with Angelman syndrome usually have a happy demeanor with frequent laughing and smiling. Here is information about the possible relationships between the changes in the brain of patients and their demeanor.

How is laughter characterized in Angelman syndrome?

Having a happy demeanor appears to be a consistent trait in Angelman syndrome. A review article found that out of 64 studies, which included 842 Angelman patients, all but four of those studies mentioned the patients being happy or laughing.

Angelman syndrome patients were more likely to be cheerful compared to patients with other forms of mental disability such as Down syndrome or Prader-Willi syndrome, according to one study. Another study, however, did not see a difference in unprovoked laughter between Angelman syndrome patients and other patients.

Researchers also reported inappropriate laughter or laughter unrelated to the situational context in Angelman syndrome patients. These cases of laughter may be due to increased anxiety such as, for example, during blood draws. Other studies have shown that children do not appear to laugh indiscriminately but actually laugh more during social interactions compared to non-social circumstances.

Angelman syndrome patients may laugh less as they get older. Laughter may also diminish if patients are experiencing uncomfortable health problems such as gastroesophageal reflux disease.

What triggers laughter?

Research has shown that several areas of the brain play a role in laughter. These regions include portions of the frontal cortex, which is essential for thinking ability, the nucleus accumbens, which plays a role in pleasure, the supplementary motor area, which controls the movements important for laughter and smiling, and several other regions. Imaging studies also showed that most humor-related brain activities occurred in the left hemisphere of the brain.

Why are patients prone to laugh more often?

Researchers do not fully understand why patients with Angelman syndrome are so prone to laughing. They had suggested that laughter may be related to seizures (gelastic seizures). However, no evidence supports this idea.

Imaging studies have shown some differences in the structure of the brain of children with Angelman syndrome. Patients had a smaller nucleus accumbens and globus pallidus (a region near the nucleus accumbens) in the left hemisphere of the brain. The numbers of nerve fibers in the connections between several brain regions were also lower. These differences may be responsible for causing patients to have trouble regulating laughter.


Last updated: Jan. 11, 2021


Angelman Syndrome News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.