Impairment of articulating words (speaking), with normal comprehension and memory of words. This is a motor disorder which involves the various muscles of the face, lips, tongue, and vocal cords that are used in speech. Dysarthria can be the result of lower motor neuron paralysis or upper motor neuron paralysis. It can also reflect incoordination of muscles due to cerebellar damage, rigidity of muscles due to damage to the extrapyramidal system, or even repetitive muscle spasms as occur in stuttering.