Dysarthria

Also called Slurred speech, Motor speech disorder

Speech that's slurred, quiet or slow because the muscles are weak: the language underneath is fine, and that changes what help looks like.

What it is

Dysarthria is unclear speech caused by weakness, stiffness or poor coordination of the muscles that make speech: lips, tongue, palate, voice box and the breath behind them. It's in the Health A-Z as dysarthria. It follows stroke, brain injury, cerebral palsy, Parkinson's, MND, MS and other conditions of the nervous system.

The thing a listener has to hold on to: the person has chosen exactly the right words in exactly the right order. Only the delivery has changed. Nothing about dysarthria touches understanding or thinking.

Who it can help

Anyone whose speech is hard to follow for muscular reasons, whether mild and tiring by evening or severe enough that a stranger catches nothing. And the people who listen to them, who do more of the work than they realise.

It's not the right frame for aphasia, where the language itself is affected, nor for apraxia of speech, where the muscles are strong but the plan for moving them is lost. The three often travel together after a stroke and a therapist will tell you the mix.

How it works

Speech needs breath support, voice, resonance and precise articulation, and dysarthria can take any of them. Weak breath gives short, quiet phrases. A weak palate gives nasal speech. Slow or imprecise tongue and lips blur the consonants, and consonants are what carry meaning, so a listener loses the words before they lose the tune.

Therapy works on what's left: slowing down, over-articulating, taking a breath every few words, and loud, clear voice work where the condition allows. Some people learn to spell the first letter of each word on an alphabet board as they say it, which slows them and gives the listener a second clue. Intelligibility often doubles with that alone.

When speech won't carry the message, AAC carries it instead, and for dysarthria that's usually text-based: the person types what they'd have said. Voice amplifiers help the quiet rather than the unclear.

Getting started

As the listener: face the person, in a quiet room, and watch the mouth. Tell them honestly which word you lost rather than guessing the whole sentence. Agree a repair strategy, such as spelling the word or saying it a different way.

As the speaker: shorter phrases, a breath between them, and the first-letter trick above. Keep a text-to-speech app on your phone for noisy places and strangers.

If speech is expected to change, as in MND or Parkinson's, start voice banking while it's still clear. It costs nothing to have and a great deal to have missed.

Where to get help

Speech and language therapy through the GP or the neurology team; the RCSLT describes the service. The condition charities each have communication guidance: the Stroke Association, Parkinson's UK, the MND Association and Ataxia UK. For a device, ask the therapist about a referral to your regional specialised AAC service.