Expert Articles

Understanding Selective Mutism

Author: Ms. Yo Yo Lee
Speech Therapist at Edge Development Centre

Kiu Kiu is attending preschool. She enjoys reading, ballet dancing, and drawing, and has won medals in ballet and drawing competitions. Her teachers often praise her as a well-behaved child who is attentive in class. Kiu Kiu’s mother once told me that she loves going to school, and even when she has a cold, as long as she doesn’t have a fever, she insists on wearing a mask to school. However, since starting preschool, Kiu Kiu has not spoken a word at kindergarten for over a year. She is unable to answer the teacher’s questions, sing nursery rhymes with her classmates, or use verbal expressions during role-playing games. Most of the time, she communicates with her teacher and classmates using gestures and body movements. Some may think that Kiu Kiu is just introverted or shy, but the truth is that this situation is not simply a matter of being “afraid to speak,” but rather a type of anxiety disorder related to communication called selective mutism.

What is selective mutism?

Selective mutism is a relatively rare anxiety disorder that typically appears during the preschool stage. Children with selective mutism have basic language and communication skills and can speak and communicate with close people in a comfortable environment (such as at home). However, in certain environments (such as school, extracurricular centers, and public places), they become too anxious to speak or can only speak in a soft voice. Some children may even experience physical stiffness or feverishness. In a 1998 epidemiological survey conducted in Finland, researchers found a prevalence rate of 2% for selective mutism during the early primary school years (meaning that, on average, there are two cases of selective mutism per 100 students). Additionally, the disorder is more common in girls than boys, with a ratio of 3:2. According to statistics from Taiwan, one in every 140 elementary school students is affected by selective mutism (a prevalence rate of 0.7%). Although there is currently no representative data on selective mutism in Hong Kong, we should not overlook its impact on local students. In the context of Oriental education and culture, teachers tend to appreciate quiet, disciplined students who maintain order in class. Moreover, since silent children rarely disrupt the class, it is more challenging to identify the condition early on. It is safe to say that this disorder may be more common than we imagine!

Selective mutism is different from general shyness.

Shy children typically show similar social behaviours in different environments; they may be quiet, introverted, slow to warm up, and reserved. Given some time (a few minutes or a couple of encounters), they gradually relax and integrate into social environments. In contrast, children with selective mutism are often described as “two different people.” In relaxed environments, they can speak freely and may even be talkative at home. However, in specific environments, even after a long period of adaptation (e.g., one semester or even a year), they still struggle to speak, with only slight improvements.

Early diagnosis and treatment

If parents suspect their child has selective mutism, they should consult a child psychiatrist. The symptoms of selective mutism overlap with those of other anxiety disorders and developmental disabilities. A child psychiatrist can help with differential diagnosis to determine whether the child’s condition is selective mutism or another situation or if multiple issues are present simultaneously. Once an accurate diagnosis is obtained, parents can seek appropriate treatment services based on the doctor’s recommendations. Professionals involved in providing selective mutism treatment typically include clinical psychologists, speech therapists, and counselling psychologists. When seeking services, parents should pay attention to the characteristics and scientific theoretical foundations of different treatment approaches. Currently, “behavioural therapy” and “cognitive-behavioural therapy” have the most research evidence supporting their effectiveness. How do speech therapists use behavioural therapy to help children speak? How can parents cooperate? I will discuss this in the next instalment.

1,000 FAQ
Understanding Selective Mutism