Selective Mutism

By Lily Phan (Psychologist)

What is selective mutism?
Selective mutism is a debilitating condition where an individual, most commonly a child, persistently fails to speak in social situations where speech is expected (Diliberto & Kearney, 2016; Krysanski, 2003; Viana et al., 2009). Associated selective mutism features include excessive shyness, social isolation, and clinging (American Psychiatric Association, 2013). Children with selective mutism often refuse to speak at school, leading to academic or educational impairment (American Psychiatric Association, 2013).

How common is selective mutism and how long does it occur for?
Beesdo, Knappe and Pine (2009) state that childhood is the core risk phase for the development of anxiety symptoms and syndromes, ranging from transient mild symptoms to full-blown anxiety disorders. Typically diagnosed in childhood, selective mutism can last from a few months to several years (Krysanski, 2003). Selective mutism is relatively rare and has not been included as a diagnostic category in epidemiological studies of the prevalence of childhood disorders (American Psychiatric Association, 2013).

Is selective mutism an anxiety disorder?
Yes, as per the Diagnostic and Statistical Manual of Mental Disorders - Fifth Edition (DSM-V; American Psychiatric Association, 2013), selective mutism is listed among anxiety disorders. The current review of literature confirms that anxiety is a prominent symptom in many children with selective mutism (Hua & Major, 2016; Muris & Ollendick, 2015). Further, research on the etiology and treatment of selective mutism also corroborates the conceptualisation of selective mutism as an anxiety disorder (Muris & Ollendick, 2015).

Why is selective mutism a thing, and what can be done?
Selective mutism is a heterogeneous disorder associated with a number of individual and family factors including developmental disorders or delay and particular temperamental, personality, environmental, developmental, genetic and physiological factors (American Psychiatric Association, 2013; Hua & Major, 2016; Standart & Couteur, 2003). 

Several randomised studies in the past few years have supported the efficacy of psychosocial interventions based on a graduated exposure to situations requiring verbal communication (Hua & Major, 2016). Less data is available regarding the use of pharmacologic treatment, though some studies suggest a potential benefit (Hua & Major, 2016).

What are the criteria for diagnosis of selective mutism?
The diagnostic criteria for Selective Mutism 312.23 (F94.0), as per the DSM-V (American Psychiatric Association, 2013) are:
Criteria A. Consistent failure to speak in specific social situations in which there is an expectation for speaking despite speaking in other situations. 
Criteria B. The disturbance substantially interferes with the individual's education, occupational achievement, and social communication.
Criteria C. The duration of the disturbance is at least one month and is not limited to the first month of school or kindergarten. 
Criteria D. The failure to speak within the context of an environment is not attributable to a lack of knowledge of, or comfort with, the spoken language required in the social situation.
Criteria E. The disturbance is not better explained by a communication disorder and does not occur exclusively during the course of Autism Spectrum Disorder, schizophrenia, or another psychotic disorder.

What are differential diagnoses that may be considered?

• Social Anxiety Disorder;
• Communication Disorders;
• Neurodevelopmental disorders and schizophrenia and other psychotic disorders; and
• Oppositional Defiant Disorder (American Psychiatric Association, 2013; Diliberto & Kearney, 2016).

If you believe you or your child may have selective mutism, you may find it helpful to speak to your General Practice or contact a psychologist.

 
References:
American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (DSM-5®). American Psychiatric Pub.
Beesdo, K, Knappe, S, & Pine, D. S. (2009). Anxiety and anxiety disorders in children and adolescents: Developmental issues and implications for DSM-V. Psychiatry Clinics of North America. 32(3), 483–524. doi: 10.1016/j.psc.2009.06.002
Diliberto, A. R., & Kearney, C. A. (2016). Anxiety and oppositional behaviour profiles among youth with selective mutism. Journal of Communication Disorders. 56. 16-23. https://doi.org/10.1016/j.jcomdis.2015.11.001
Hua, A. & Major, N. (2016). Selective mutism. Current opinion in pediatrics. 28(1), 114-120. doi.org/10.1097/MOP.0000000000000300
Krysanski, V. L. (2003). A Brief Review of Selective Mutism Literature, The Journal of Psychology, 137(1), 29-40, DOI: 10.1080/00223980309600597
Muris, P., & Ollendick, T.H. (2015). Children who are anxious in silence: A review on selective mutism, the new anxiety disorder in DSM-5. Clinical Child and Family Psychology Review. 18, 151–169. https://doi.org/10.1007/s10567-015-0181-y
Standart, S. & Couteur, A. L. (2003). The quiet child: A literature review of selective mutism. Child and Adolescent Mental Health. 8(4): 154-160. doi.org/10.1111/1475-3588.00065
Viana, A. G., Beidal, D. C., & Rabian, B. (2009). Selective mutism: A review and integration of the last 15 years. Clinical Psychology Review. 29(1), 57-67.