Selective Mutism

The name was changed to reflect that the silence is involuntary. It remains disputed. Situational mutism was proposed by Alice Sluckin and is used by activists and by autism researchers including Damian Milton, on the grounds that selective still implies a selection somebody made.

What it looks like in practice

Speech is intact. Understanding is intact. In particular settings, with particular people or in particular places, speech becomes impossible. It is not glossophobia, which spares the private conversation.

The variation is hierarchical rather than absolute, and the gradations are frequently misread:

• some join in activities fully and appear sociable while not speaking
• some speak to peers and not to adults
• some answer adults' short questions and never speak to peers
• some speak to nobody and take part in little In a severe form named progressive mutism, the condition advances until the person speaks to no one at all, including close family.

A child may be silent at school for years and speak freely, or excessively, at home. That contrast is what makes the older name plausible to an observer, and it is exactly what the current understanding rejects: the setting determines the capability.

The silence persists through consequences. People with selective mutism may remain silent when the result is shame, social exclusion or punishment, which is not how a preference behaves.

Why social anxiety is almost always present

The comorbidity figures are extreme. The majority of children diagnosed with selective mutism also have social anxiety disorder, and in the studies cited the proportion reached one hundred per cent in two of them and ninety-seven per cent in a third.

A finding that near-total raises the question of whether the two are separable at all, and the material does not answer it. What it does say is that the association is with social anxiety specifically rather than with anxiety generally.

How the autism confusion is resolved

Selective mutism is conflated with autism, particularly in young children, and most often when a child appears especially withdrawn in front of the person assessing them. The consequence named is misdiagnosis and ineffective treatment.

The distinction offered is behavioural rather than definitional. Many autistic people are also selectively mute, and where that is the case other features are usually present: stimming, repetitive behaviour, and social isolation extending to family members, including not always responding to their own name. Some autistic people are selectively mute because of anxiety in unfamiliar social settings.

The rule that follows is stated in the diagnostic criteria: where the mutism is entirely attributable to autism spectrum disorder, selective mutism is not diagnosed.

How rare the condition is

The incidence is described as not certain, and the reason is the ordinary one for a condition the public does not understand: many cases go undiagnosed. Based on reported cases the figure is commonly given as one in a thousand, or 0.1 per cent.

That number is doing less work than it appears to. It counts diagnoses of a condition whose defining feature is that the person says nothing about it, in settings where silence is often read as shyness by some observers and rudeness by others. Both readings delay a referral, and the delay is invisible in the statistics.

Where the manual finally placed it

DSM-5 describes it as a persistent difficulty speaking in specific social settings where speech is expected, such as school, despite the ability to speak in other situations. The symptoms must not be temporary and must affect the person's ability to function in the situation, and other diagnoses have to be considered. It is classified as an anxiety disorder rather than as a communication disorder, which is the placement the 1994 rename was arguing for.