Selective Mutism

Selective Mutism is a mental disorder where individuals (most commonly children) do not initiate speech or reciprocally respond when spoken to by others. This lack of speech occurs in both social interactions with children or adults. Children will however, speak in their home in the presence of immediate family members.

• Selective mutism is rare, and the point prevalence using various clinic or school samples ranges between 0.03% and 1%.^[1]
• There does not appear to be a sex or ethnicity difference.
• It is more likely to occur in young children than adults.^[2]

• The onset of selective mutism usually begins before age 5 years
• It often comes to clinical attention when the school age years begin and there is a need for social interactions and performance tasks.
  • This can lead to severe impairment in social or school functioning, or teasing from peers.
• The course of selective mutism is unclear, but most individuals will outgrow the symptoms.
  • Social anxiety symptoms may continue however, and individuals may continue to meet criteria for this disorder.^[3]

• In the clinical setting, children with selective mutism are almost always given an additional diagnosis of social anxiety disorder.^[4]

• Children may model parents who have social inhibition, which increases risk for selective mutism.^[5]
• Parents who are described as overprotective may have children at increased risk for selective mutism.

Consistent failure to speak in specific social situations in which there is an expectation for speaking (e.g. - at school) despite speaking in other situations.

The disturbance interferes with educational or occupational achievement or with social communication.

The duration of the disturbance is at least 1 month (cannot be during first month of school).

The failure to speak is not attributable to a lack of knowledge of, or comfort with, the spoken language required in the social situation.

The disturbance is not better explained by a communication disorder (e.g. - childhood-onset fluency disorder) and does not occur exclusively during the course of autism spectrum disorder, schizophrenia, or another psychotic disorder.

• Children with selective mutism often refuse to speak at school, which can cause academic or educational impairment.
• The lack of speech can also interfere with social communication. Children may sometimes use nonspoken or nonverbal methods (e.g. - grunting, pointing, writing) to communicate.
• They may similarly be willing or eager to perform or engage in social encounters when speech is not required (e.g. - nonverbal parts in school plays).
• Generally, children with selective mutism have normal language skills.

• Selective Mutism Questionnaire (SMQ)^[6]

• The underlying psychopathology and pathophysiology of selective mutism is thought to be similar to social anxiety disorder due to their many overlapping features.

• Communication disorders
  • Selective mutism should be differentiated from speech disturbances due to a communication disorder, such as language disorder, speech sound disorder, childhood-onset fluency disorder (stuttering), or pragmatic (social) communication disorder.
  • Unlike selective mutism, the speech disturbance in these other conditions is not restricted to a specific social situation.
• Neurodevelopmental disorders and schizophrenia and other psychotic disorders
  • Individuals with an autism spectrum disorder, schizophrenia or another psychotic disorder, or severe intellectual disability may have problems in social communication and be unable to speak appropriately in social situations.
  • In contrast, selective mutism should be diagnosed only when a child has an established capacity to speak in some social situations (e.g. - typically at home).
• Social anxiety disorder (social phobia)
  • Social anxiety disorder and selective mutism have a high overlap in the symptom criteria. Commonly, an individual with selective mutism will also receive a diagnosis of social anxiety disorder.^[7]

• As clinically indicated.

• As clinically indicated.

• Cognitive behavioural therapy is the main treatment for selective mutism. Exposure is the most important component, and involves gradually exposing the child to speaking tasks with parental/therapist support.^[8]

• Dow, S. P. et al. (1995). Practical guidelines for the assessment and treatment of selective mutism. Journal of the American Academy of Child & Adolescent Psychiatry, 34(7), 836-846.