Overview
Selective Mutism (SM) is an anxiety disorder with a prevalence of 1-2%.[1,2] The condition is characterized by the consistent absence of speaking in specific situations (e.g., work or school), while normally speaking in other situations (e.g., home).[3]
Symptoms
According to the National Health Service (NHS) symptoms of Selective Mutism include:[4]
A sudden stillness and frozen facial expression when someone is expected to talk to another who is outside their comfort zone.
Avoiding eye contact.
Appearing nervous, uneasy or socially awkward.
Appearing rude, disinterested or sulky.
Shy and withdrawn.
Becoming stiff, tense or poorly coordinated.
Stubborn or aggressive behavior (e.g., having temper tantrums when they get home from school, getting angry when questioned by parents).
More confident children with selective mutism can use gestures to communicate (e.g., nod for "yes" or shake their head for "no").
Some children may manage to respond with a few words, or they may speak in an altered voice (e.g., a whisper).
More severely affected children tend to avoid any form of communication – spoken, written or gestured.
Selective Mutism typically occurs in early childhood. While the mean age-of-onset is between 2-5 years, symptoms may most appear when children enter school for the first time.[5] Furthermore, the disorder is more common in girls and children who have recently migrated from their country of birth.[6] Research has shown that SM has a mean duration of 8 years, after which the total absence of speech in certain situations normally lessens or disappears completely.[7]
Causes
There are a plethora of potential causes that may make an individual more prone to develop Selective Mutism. Children with sensory integration dysfunction may present with SM as this condition can cause them to “shut down” and be overwhelmed in a busy environment due to difficulty processing sensory information.[8] Selective Mutism can also result as a symptom of post-traumatic stress: in this instance, the disorder will follow a different pattern compared to traditional SM and the child will suddenly stop talking in environments where they previously had no difficulty.[9] Temperament can also play a role in the likelihood of developing SM; according to the Selective Mutism Center, children with SM often have severely inhibited temperaments, which aligns with studies that point to individuals with inhibited temperaments being more prone to anxiety.[10] Muris and Ollendick (2015) also point out potential environmental and biological causes; they found that parents of children with Selective Mutism demonstrated higher levels of shyness, social anxiety, and preference for solitary activities.[11] Furthermore, a genetic variation of the CNTNAP2-gene seems to be involved in SM, social anxiety, and socially anxious traits.[12]
Diagnosis
The DSM-5 specifies the following criteria to confirm a Selective Mutism diagnosis:[13]
The selective absence of speech should be present for at least 1 month, since many young children become anxious when confronted with a completely new situation (e.g., entering school for the first time).
The absence of speech hinders the child functioning well at school or in social interactions.
The failure to speak is not attributable to lack of knowledge, or a discomfort with, the spoken language in the social situation.
The lack of speech 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.
A common misconception of SM is that a child with Selective Mutism must have autism; while a child may have both SM and ASD, the two conditions are not mutually inclusive. In a study by Ludlow et al. (2022) children with SM and ASD showed significantly higher levels of social anxiety and sensory avoidance compared to children who only had Selective Mutism.[14] Further, sensory avoidance helped differentiate children with ASD from children with social anxiety, as those with social anxiety typically do not have sensory issues.[15]
To determine a diagnosis, a licensed medical professional (e.g., a physician) familiar with Selective Mutism will conduct a parental interview to find out more about the child’s social interaction and development history, other manifestations of anxiety, temperament, home life, and medical history.[16] Afterwards, the medical professional will meet with the child and assess their interpersonal communication skills. Regardless whether the child speaks or remains silent in the presence of the evaluating physician, a diagnosis of SM can still be made.[17]
Since roughly 20-30% of children with SM present with an abnormality of speech and language, a thorough speech and language evaluation is often ordered.[18]
Complications
Muris and Ollendick (2015) report that children who have previously suffered from SM continue to have communication problems, underperform at school or work, and display higher rates of psychiatric disorders.[19] A study by Tomohisa et al. (2022) furthered that long-term outcomes include elevated rates of phobic disorders (particularly social phobia), persistent communicative problems, and reduced self-esteem.[20]
Treatment
An early start to treatment is associated with better prognosis.[21] Treatment for Selective Mutism does not typically focus on the speaking itself, but on reducing the anxiety associated with speaking.[22]
The Selective Mutism Center presents the following as potential treatments:[23]
Behavioral Therapy: Positive reinforcement and desensitization techniques are the primary behavior treatments for SM, as well as removing all pressure to speak and placing an emphasis on understanding the child and acknowledging their anxiety. Such techniques include taking a child to school when few people are around to get the child to practice speaking and allowing parents to spend time with the child within the class.
Play Therapy, Psychotherapy, and Other Psychological Approaches: These approaches should focus on removing pressure to talk and place emphasis on helping the child relax and open up. Children with mutism may be scared to speak and this approach will help them identify their level of fear in a particular situation.
Cognitive Behavioral Therapy: CBT-trained therapists help children modify their behavior by helping them redirect their fears and worries into positive thoughts.The focus should be on emphasizing the child's positive attributes, building confidence in social settings, and lowering overall anxiety and worries.
Medication: If children are not making enough progress with behavioral therapy alone, medication may be recommended to reduce their anxiety level. Serotonin reuptake inhibitors (SSRIs) such as Prozac, Paxil, Celexa, Luvox, and Zoloft are very effective in the treatment of anxiety disorders.
In addition to the aforementioned modalities, parents can utilize the following techniques to help ease the child’s anxiety over speaking:[24]
Self-Esteem Boosters: Parents should emphasize their child’s positive attributes (e.g., show off their child’s artwork and ask them to explain their artwork to family members and close friends)
Frequent Socialization: Encourage as much socialization as possible without pushing a socially anxious child (e.g., arrange frequent play dates with classmates or small group interactions with individuals the child knows well)
School Involvement: It’s essential that the school understands that children with Selective Mutism are not being defiant nor stubborn by not speaking: they truly cannot speak. Explain to their teacher that a child needs to feel that it is OK for them not to speak if they are unable or uncomfortable.
If you believe you or your child may have Selective Mutism, please reach out to a licensed mental health professional (e.g., a psychotherapist, psychologist or psychiatrist) for guidance and support.
Contributed by: Maria Karla Bermudez
Editor: Jennifer (Ghahari) Smith, Ph.D.
References
1 Rozenek, E. B., Orlof, W., Nowicka, Z. M., Wilczyńska, K., & Waszkiewicz, N. (2020). Selective mutism - an overview of the condition and etiology: is the absence of speech just the tip of the iceberg?. Mutyzm wybiórczy – opis zaburzenia i etiologia: czy wybiórczy brak mowy jest zaledwie wierzchołkiem góry lodowej?. Psychiatria polska, 54(2), 333–349. https://doi.org/10.12740/PP/OnlineFirst/108503
2 Rodrigues Pereira, C., Ensink, J. B. M., Güldner, M. G., Lindauer, R. J. L., De Jonge, M. V., & Utens, E. M. W. J. (2021). Diagnosing selective mutism: a critical review of measures for clinical practice and research. European child & adolescent psychiatry, 10.1007/s00787-021-01907-2. Advance online publication. https://doi.org/10.1007/s00787-021-01907-2
3 Ibid.
4 NHS. (2023, February 17). Selective Mutism . NHS choices. https://www.nhs.uk/mental-health/conditions/selective-mutism/#:~:text=Selective%20mutism%20is%20an%20anxiety,untreated%2C%20can%20persist%20into%20adulthood.
5 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(2), 151-169. https://doi.org/10.1007/s10567-015-0181-y
6 NHS (2023)
7 Muris & Ollendick (2015)
8 NHS (2023)
9 Ibid.
10 What is selective mutism. Selective Mutism Anxiety & Related Disorders Treatment Center | SMart Center. (2023, April 19). https://selectivemutismcenter.org/whatisselectivemutism/
11 Muris & Ollendick (2015)
12 Ibid.
13 American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 5th ed. Washington, DC: American Psychiatric Association; 2013.
14 Ludlow, A. K., Osborne, C., & Keville, S. (2022). Selective Mutism in Children With and Without an Autism Spectrum Disorder: The Role of Sensory Avoidance in Mediating Symptoms of Social Anxiety. Journal of autism and developmental disorders, 10.1007/s10803-022-05674-0. Advance online publication. https://doi.org/10.1007/s10803-022-05674-0
15 Ibid.
16 SMart Center (2023)
17 Ibid.
18 Ibid.
19 Muris & Ollendick (2015)
20 Tomohisa, Y., Yumi, I., & Inoue, M. (2022). Long-term outcome of selective mutism: factors influencing the feeling of being cured. European child & adolescent psychiatry, 10.1007/s00787-022-02055-x. Advance online publication. https://doi.org/10.1007/s00787-022-02055-x
21 Rozenek et al. (2020)
22 NHS (2023)
23 SMart Center (2023)
24 Ibid.