Selective mutism in a child – when does silence at kindergarten or school need a consultation?

Selective mutism is an anxiety disorder in which a child speaks freely at home, but in kindergarten, school, or other specific social situations is unable to produce a single word – despite having a fully intact ability to speak. It is not shyness, stubbornness, or manipulation: anxiety literally blocks speech. The sooner a parent and teacher recognise this mechanism, the sooner effective support can be started.

What is selective mutism?

Selective mutism (selective mutism) is an anxiety disorder. In the classification currently in force in Poland, ICD-10, it has the code F94.0 and belongs to the group of disorders of social functioning with onset specific to childhood. In the newest classification, DSM-5 (code 313.23), and in ICD-11 (code 6B06), which is being prepared for implementation, selective mutism is classified directly among the anxiety disorders – this reflects the current state of clinical knowledge.

Selective mutism is not a speech-sound difficulty, a language development delay, or a form of autism spectrum disorder. A child with selective mutism has full language competence – they understand instructions, build sentences, and talk freely at home. The problem lies in anxiety mechanisms that, under certain conditions, block speech. This state is sometimes compared to a kind of “voice block” caused by anxiety – similar to the way a fear of heights prevents someone from climbing a ladder, even though their legs work perfectly well.

The disorder affects an estimated 0.7–1% of school-age children (Bergman, Piacentini, McCracken, 2002). Some studies report a range from 0.03% to 2.2%, depending on the population and methodology. Symptoms most often appear between the ages of 2 and 5, but the diagnosis is often made only after many months – once the surroundings stop explaining the child's silence as adaptation or shyness.

How to recognise selective mutism? Symptoms in a child

The key signal is a clear contrast in behaviour between different environments. At home the child speaks freely, while in kindergarten or school they do not speak at all, or speak only in a whisper to one chosen person. The teacher reports that the child never speaks up; the parents hear this for the first time with astonishment, because at home the child talks readily.

Other symptoms that may accompany selective mutism:

• a “frozen” facial expression, a stiff posture, and avoiding eye contact in social situations,
• non-verbal communication at the institution: nodding, pointing, writing or drawing instead of speaking,
• speaking in a whisper or through an intermediary – for example whispering to a parent who then “translates” for the teacher,
• difficulty with everyday activities outside the home: asking for help, using the toilet, eating,
• physical symptoms – stomach aches, nausea, headaches – appearing before leaving for the institution and easing on weekends,
• gradual withdrawal from peer relationships and avoiding situations in which the child might be asked to speak.

Selective mutism versus ordinary shyness – how to tell them apart?

Every child can be initially quiet in a new environment – that is a normal part of adaptation. The line beyond which it is worth seeking help is set by several diagnostic criteria taken from the DSM-5:

• Duration: the silence persists for longer than one month and is not limited to the first month at a new institution, when adaptation is natural.
• Consistency: the child is consistently silent in the same situations or with the same people, not just occasionally.
• Contrast: in conditions the child considers safe, they speak freely – this contrast is the most important clue.
• Effect on functioning: the silence interferes with learning, building peer relationships, or everyday functioning at the institution.
• Exclusion of other causes: the silence is not due to unfamiliarity with the language spoken in that environment, nor to another communication disorder.

A shy child, after the adaptation phase, gradually “opens up” and starts to talk, laugh, and answer questions. A child with selective mutism does not grow out of the problem on their own – or grows out of it only with great difficulty, after many years, during which the anxiety mechanisms become more and more deeply entrenched.

When and why does selective mutism appear?

The causes are multifactorial. Current clinical understanding takes into account:

• Family predisposition: in families of children with selective mutism, anxiety disorders, marked shyness, or a history of communication difficulties are found more often than average.
• High reactivity of the nervous system: children with a temperament described as behavioural inhibition – withdrawing from the unknown, new people, or noise – are more susceptible to selective mutism.
• Environmental factors: moving house, a change of kindergarten or carer, bilingualism, or a situation in which the child felt publicly judged for the way they speak – these can act as a trigger or intensify the disorder.
• Coexisting language difficulties: in some children with selective mutism, a delay in speech development, auditory-processing difficulties, or articulation difficulties co-occur, which can raise the anxiety around speaking in front of others.

Selective mutism is not the result of parenting mistakes or trauma. Nor is it a form of manipulation by the child. It is an anxiety disorder with a neurobiological basis, which requires planned, specialist help.

Who makes the diagnosis and what does the diagnostic process look like?

Under Polish regulations, the formal diagnosis of selective mutism is made by a child psychiatrist. It is the visit to the psychiatrist that confirms the diagnosis and rules out other causes of the silence. The diagnostic process, however, is a team effort and usually involves:

• The child psychiatrist – makes the diagnosis, assesses the severity of the anxiety, and, if needed, consults on pharmacological support.
• The child psychologist – assesses the anxiety mechanisms, developmental history, and communication patterns across different environments, and leads the main therapeutic work.
• The speech therapist – assesses language competence and rules out a primary speech or language disorder (delayed speech development, articulation disorders, auditory-processing difficulties) that could be behind the child's silence. The speech-therapy assessment should take place in conditions where the child speaks – ideally a clinic room a trusted parent gradually brings the child into.

The differential diagnosis includes, among other things, autism spectrum disorders, delayed speech development, developmental language disorder (DLD), natural adaptation to a new environment, and the context of bilingualism. What matters most are detailed observations: when the silence appeared, with whom and where the child speaks, and how the surroundings react to it.

If you are wondering how to prepare for a diagnostic visit at the speech therapist, it is worth bringing a short description of your observations from home and kindergarten – this helps the specialist a great deal during the first meeting.

What does the therapy for selective mutism look like?

The basis of therapy for selective mutism is a cognitive-behavioural (CBT) approach with gradual exposure – systematically and slowly getting the child used to situations that require speaking. The most commonly used protocol is the small-steps method (sliding-in), described at length in the Polish edition of Maggie Johnson and Alison Wintgens's book Mutyzm wybiórczy. Kompendium wiedzy [Selective Mutism. A compendium of knowledge] (Harmonia Universalis, Gdańsk).

The key principle: therapy takes place where the problem actually occurs – in kindergarten, school, or the playground, not only in the therapy room. What does this look like in practice?

1. We start with a situation in which the child speaks freely – for example with a parent in an empty kindergarten room after hours.
2. A new person is then gradually “slid into” this situation (first the coordinator from the institution, then further people): first a background presence, then a quiet activity alongside, then brief non-verbal contact, and finally an exchange of words.
3. Every step is a success the child needs to calmly absorb before moving on. There is no pressure of time or pressure to speak.
4. We do not reward speaking with loud praise – drawing attention to the act of speaking itself can paradoxically increase the anxiety around the next occasion.

According to the Polish Selective Mutism Foundation, therapy sessions using the small-steps method are usually planned 3–5 times a week for 15–20 minutes, in a calm room the child already knows. In older children, who understand the mechanism of their own anxiety, the method is supplemented with classic cognitive-behavioural therapy (CBT) – it helps the child recognise, name, and gradually get used to anxiety-provoking situations.

In older children, or in cases of very severe anxiety, the child psychiatrist may consider pharmacological treatment, most often with a selective serotonin reuptake inhibitor (SSRI). Such a decision is always individual and remains the psychiatrist's responsibility – medication supplements behavioural therapy, it does not replace it.

The duration of therapy varies widely. Some children make clear progress within a few months of intensive cooperation; others need a longer process. The earlier support is put in place, the better the outlook – it is not worth waiting for the child to “start talking on their own”.

Therapy for selective mutism differs from classic speech therapy, which focuses on pronunciation or expanding language. You will find many practical tips about the first visit to a speech therapist in our article on preparing a child for the first speech-therapy visit in case of communication difficulties – some of them also work well for selective mutism.

The role of parents, teachers, and the kindergarten in therapy

Therapy for selective mutism cannot be the work of the child and the therapist alone in the therapy room. Consistent support from the entire surroundings is a condition for success. At the institution, a key role is played by the coordinator – a specific, trusted person (usually the class teacher or the school pedagogue) who “introduces” the therapy into the kindergarten or school.

What parents can do:

• inform the institution about the disorder and its mechanism – teachers need to know that the silence is anxiety, not disobedience,
• not put pressure on the child to speak, and not apologise for the child or be embarrassed by them in public situations,
• regularly carry out with the child the exercises recommended by the therapist,
• make sure the child does not become socially isolated – walks, playing with peers in small groups, and contact in safe conditions are an important part of the therapy.

What teachers and educators can do:

• not call the child to the board and not ask questions that require a loud answer in front of the whole class,
• accept non-verbal communication – nodding, pointing, writing on paper – without pointing out that the child is silent,
• build a safe one-to-one relationship: a short chat during break time, a shared activity in a smaller group, a non-verbal activity alongside,
• regularly exchange information with the parents and the therapist about progress, difficulties, and noticeable signals.

The statement from a counselling centre and help in Gdańsk – where to start?

A child with selective mutism can receive, from a Polish psychological-pedagogical counselling centre (PPP), a statement of the need for special education due to the risk of social maladjustment. The statement obliges the kindergarten or school to draw up, within 30 days, an IPET (Individual Education-and-Therapy Programme), which formally sets out how teachers should work with the child – among other things, that they do not call on the child for an oral answer, accept written answers, and provide therapy at the institution.

The application for the statement is submitted by the parent or legal guardian to the PPP responsible for the institution's catchment area, together with a certificate from the psychiatrist. To make the adjudicating panel's work easier, it is worth asking the doctor to explicitly note the presence of anxiety disorders, not only the term “selective mutism” on its own. The procedure, together with gathering the documentation, usually takes from a few weeks to a few months – which is why it is worth starting it alongside consultations with specialists.

A first, simple step can be a speech-therapy consultation. The speech therapist assesses the child's language competence, rules out a speech or language disorder as the cause of the silence, and helps plan the further path – to a child psychiatrist, a psychologist, or a PPP. An early consultation does not decide anything in advance, but it gives the parent a picture of the situation and a concrete plan, instead of helpless waiting.

At StacjaMowa – the Speech and Function Therapy Centre in Gdańsk – we run speech therapy for children as well as consultations for parents who are wondering where to start. We can assess whether the child's silence is linked to language difficulties, or whether it mainly requires psychological support, and help you plan the next steps. If selective mutism co-occurs with delayed speech development, our article on delayed speech development – when a paediatric speech therapist is really needed may also be useful.

Sources and literature

• 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 & Adolescent Psychiatry, 47(8), 938–946. Accessed: pubmed.ncbi.nlm.nih.gov/12162629.
• Johnson, M., Wintgens, A. (2018). Mutyzm wybiórczy. Kompendium wiedzy. [Selective Mutism. A compendium of knowledge]. Gdańsk: Harmonia Universalis (Polish edition of The Selective Mutism Resource Manual).
• American Psychiatric Association (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed., DSM-5). Washington, DC: APA – criteria 313.23 Selective Mutism.
• World Health Organization. ICD-10, code F94.0 Selective Mutism, and ICD-11, code 6B06 (anxiety disorders). Accessed: icd.who.int.
• Cohan, S. L., Chavira, D. A., Stein, M. B. (2006). Practitioner review: psychosocial interventions for children with selective mutism. Journal of Child Psychology and Psychiatry, 47(3), 284–300.
• Selective Mutism Foundation (Poland) – the small-steps method, materials for teachers and parents. Accessed: mutyzm-wybiorczy.org.pl.
• Bystrzanowska, M. (2017, 6th ed. 2021). Mutyzm wybiórczy. Poradnik dla rodziców, nauczycieli i specjalistów. [Selective mutism. A guide for parents, teachers, and specialists]. Kraków: Oficyna Wydawnicza Impuls.