Stammering

A neurological condition that affects the rhythmic flow of speech, causing involuntary repetitions, prolongations, or blocks of sounds, syllables, or words. Blocking describes audible or silent moments when a person is unable to produce a specific sound despite intending to. Stammering affects approximately 8% of children and 2% of adults worldwide. For accessibility, stammering presents significant challenges with voice-controlled interfaces such as smart speakers and voice assistants, which may time out during blocks, fail to recognise prolonged sounds, or cut users off before they finish speaking. Designing inclusive voice interfaces requires accommodating diverse speech patterns rather than assuming fluent speech as the default.