Aggression

Aggression refers to any behaviour that has the potential to cause injury to another person. When we use the phrases ‘aggression’ or ‘aggressive behaviour’, we do not mean to imply that an individual with Smith-Magenis syndrome is intentionally trying to hurt another person.

What is the prevalence of aggression in Smith-Magenis syndrome?

Prevalence estimates of physical aggression vary widely, from 38% to 93%, and research shows that individuals with Smith-Magenis syndrome are more likely to show this behaviour than individuals with intellectual disability of heterogeneous cause. The reason different studies have led to different estimates is probably due to the different methods they have used.

What forms of aggression are common in Smith-Magenis syndrome?

Similarly to self-injury, the forms of aggression shown by individuals with Smith-Magenis syndrome vary widely.  Many individuals show aggressive behaviours common in other syndromes such as hitting and punching, but less common behaviours are also prevalent such as biting and strong hugging.

Dr. Jenny Sloneem and her team studied aggressive behaviour in Smith-Magenis syndrome. Results showed that more than 80% of individuals showed hitting and grabbing behaviour, suggesting that these are the most common forms of aggression. Moreover, biting, kicking and pinching were shown by more than half of individuals.

What causes aggression in Smith-Magenis syndrome?

Research by Sloneem et al (2011) found that aggression in Smith-Magenis syndrome served social communicative functions, such as obtaining social interaction with another person, escape from demands, and access to tangibles.

The severity of aggression in individuals with Smith-Magenis syndrome has been strongly associated with impulsivity characteristic of the syndrome, with those with greater impulsivity more likely to develop aggressive behaviours.

Other risk factors for displaying aggression are hyperactivity and autistic behaviours.