At home your child never stops. They narrate their Lego, boss their little brother around, sing in the bath. Then the kindy educator pulls you aside at pick-up and says, gently, "She hasn't said a word all term." You might even have been met with doubt when you explained how chatty she is at home.
If that sounds familiar, you may be looking at selective mutism. It's not well understood, so let's go through what it is and what sensible support looks like.
Anxiety, not a choice
Selective mutism is classified as an anxiety disorder in the DSM-5-TR. A child speaks comfortably in some settings, usually home, and consistently doesn't speak in others where speaking is expected, such as kindy or school. For a diagnosis this has to have lasted at least a month, and not just the first month of kindy or school, and it can't be explained simply by a child learning a new language or by a speech or language disorder on its own (Muris & Ollendick, 2015). That month is the diagnostic bar, not a waiting period: if you're worried, you can ask for help straight away.
The word "selective" is unhelpful, because it sounds like the child is choosing. They're not. Older children describe their words getting stuck or their throat closing over, and many want very much to talk. A better picture is a freeze response: the body's alarm goes off in a social situation and speech is the first thing to shut down. Some families and clinicians prefer the term "situational mutism" for exactly this reason, so you may see both; selective mutism is still the formal diagnostic name. So we never describe these children as "refusing" to speak. It isn't defiance, and treating it as defiance makes things worse.
How it shows up
The classic picture is a child who talks freely at home, often loudly, and goes quiet the moment someone from outside the family circle appears, grandparents included. At kindy or school they may nod, point, shrug, draw, or whisper to one trusted friend. Some children communicate a great deal without their voice. Others freeze more completely and find it hard to eat, use the toilet or ask for help while they're there.
You might notice a still, "frozen" face, eyes down, and a very long warm-up. It's usually first noticed between three and five, when a child starts kindy, but diagnosis often lags years behind (Steffenburg et al., 2018).
How common is it?
Uncommon, but not rare. A large school-based study in the United States found a prevalence of about 0.7 per cent (Bergman, Piacentini & McCracken, 2002), and reviews put the figure somewhere between 0.03 and 1 per cent depending on how it's measured (Muris & Ollendick, 2015). Put plainly, a kindy or primary school of a few hundred children probably has at least one.
Children growing up with more than one language often go through a normal quiet period when they start in an English-speaking setting. That's different from selective mutism, though the two can occur together, which is one reason careful assessment matters.
Overlap with speech, language and autism
Selective mutism rarely travels alone. In a Norwegian study of 54 children with selective mutism, 68.5 per cent also met criteria for a developmental disorder or delay, most often in speech, language or motor skills, compared with 13 per cent of children in the comparison group (Kristensen, 2000). It makes sense: if talking already feels effortful, talking in front of unfamiliar people is a bigger ask again. The silence can also hide a speech or language difficulty, because nobody outside the home hears the child speak.
Autism overlaps too. In a Swedish service that specialises in autism assessment, 63 per cent of children referred with selective mutism were also autistic (Steffenburg et al., 2018). That's a specialised sample, so the everyday figure is likely lower, but the overlap is real. An autistic child may go quiet from sensory or social overload rather than fear of being heard, and some children have both. So we look at the whole child through a neuro-affirming lens and think about social communication differences alongside anxiety rather than assuming one explains everything.
Why early identification matters
It's tempting to hope a quiet child will simply grow out of it. Some do. But the research gives us a few reasons not to wait. In a five-year follow-up of children treated for selective mutism, 70 per cent were in full remission, and the children who were older or more severely affected when treatment began had poorer outcomes (Oerbeck et al., 2018). The same review that places selective mutism among the anxiety disorders also notes that, left unsupported, the anxiety underneath it tends to persist even where the silence eases (Muris & Ollendick, 2015).
There's a practical cost in the meantime too. A child who can't speak at kindy can't show what they know or ask for help, and finds it harder to get into play. The earlier a plan is in place, the less time a child spends quietly overlooked.
A team approach
Selective mutism is first and foremost an anxiety condition, so a psychologist experienced with childhood anxiety usually leads treatment. In our practice, diagnosis sits with a psychologist or paediatrician, and we feed in what we learn about the child's speech and language. Behavioural approaches that build up speaking in gradual, planned steps have the strongest evidence (Cohan, Chavira & Stein, 2006).
Speech pathology has a distinct job inside that team. We work out whether there's a speech sound or language difficulty underneath the silence, because if there is, anxiety treatment alone won't resolve it. We support the graded communication steps the psychologist sets and coach parents and educators in the small habits that take pressure off. A GP ties the referrals together, and educators are part of the team from the start.
How we assess without asking a child to speak
Nobody with selective mutism should be put on the spot in an assessment, so our data collection doesn't require the child to talk to us at all.
We start with you. A detailed parent interview covers speech sounds, sentence length, vocabulary and understanding at home, and where and with whom your child does and doesn't speak. Short videos of everyday chat at home let us hear your child's actual speech and language, and research shows parents can even present formal language tasks at home with good results (Klein, Armstrong & Shipon-Blum, 2013). Then we observe, at home or at kindy, sitting beside your child rather than across from them, joining their play and thinking aloud rather than asking questions. For some children a first meeting over Zoom, with you doing the talking and the camera pointed anywhere but at them, is an easier way in than a stranger in the lounge room.
You know your child's communication better than anyone, and here that knowledge is the core of the assessment, which is why parents are such a big part of therapy. If you'd like to talk it through, get in touch. Speaking Speech Pathology offers mobile speech pathology across Brisbane's south side and Logan, at home, at kindy or by video. Any actual clinical work, including assessment and therapy, happens in a consultation about your child, not from an article.
Ready for practical strategies? Read our companion article: Supporting a Child with Selective Mutism: Strategies for Home and School
Alexandra Bouwmeester is a Senior Speech Pathologist (MSPA, CPSP), certified in Hanen's It Takes Two to Talk, with over 14 years' experience and a mum of two boys. She offers mobile speech pathology to families across Brisbane's south side and Logan.
This article is general information and not a substitute for individualised speech pathology assessment or therapy. If you have concerns about your child, please speak with a qualified speech pathologist.
References
- Bergman, R. L., Piacentini, J., & McCracken, J. T. (2002). Prevalence and description of selective mutism in a school-based sample. Journal of the American Academy of Child and Adolescent Psychiatry, 41(8), 938–946.
- Cohan, S. L., Chavira, D. A., & Stein, M. B. (2006). Practitioner review: Psychosocial interventions for children with selective mutism: A critical evaluation of the literature from 1990–2005. Journal of Child Psychology and Psychiatry, 47(11), 1085–1097.
- Klein, E. R., Armstrong, S. L., & Shipon-Blum, E. (2013). Assessing spoken language competence in children with selective mutism: Using parents as test presenters. Communication Disorders Quarterly, 34(3), 184–195.
- Kristensen, H. (2000). Selective mutism and comorbidity with developmental disorder/delay, anxiety disorder, and elimination disorder. Journal of the American Academy of Child and Adolescent Psychiatry, 39(2), 249–256.
- 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.
- Oerbeck, B., Overgaard, K. R., Stein, M. B., Pripp, A. H., & Kristensen, H. (2018). Treatment of selective mutism: A 5-year follow-up study. European Child & Adolescent Psychiatry, 27(8), 997–1009.
- Steffenburg, H., Steffenburg, S., Gillberg, C., & Billstedt, E. (2018). Children with autism spectrum disorders and selective mutism. Neuropsychiatric Disease and Treatment, 14, 1163–1169.
