Stroke is the leading cause of long-term disability in the UK. About a third of stroke survivors will suffer some level of communication problems following the stroke. Such problems can affect parts or all of the motor apparatus responsible for producing speech, thus affecting clarity of speech and overall intelligibility (a condition known as dysarthria). Alternatively, stroke can affect the cognitive system for comprehending and formulating language (a condition known as dysphasia or aphasia). Some people will suffer impairment of both speech and language.