Which condition is characterized by muscle weakness affecting speech?

Dysarthria is a condition characterized by muscle weakness that affects the ability to produce speech sounds clearly. This weakness can impact various muscle groups involved in speech, including those responsible for articulation, respiration, phonation, and resonance. As a result, individuals with dysarthria may exhibit slurred, slow, or difficult speech that can vary widely in severity.

In cases of dysarthria, the underlying issue is not related to language comprehension or the planning of speech, but rather to the physical production of speech. This distinguishes it from other speech disorders. For example, aphasia primarily affects language processing and comprehension, while apraxia of speech is related to difficulty planning and coordinating the movements necessary for speech. Phonological disorders involve patterns of sound errors and do not include the muscle weakness seen in dysarthria. Understanding these distinctions highlights why the correct answer is dysarthria, as it directly relates to the physical limitations that impact spoken communication.