What resonance characteristic is typically observed in spastic dysarthria?

In spastic dysarthria, the resonance characteristic typically observed is hypernasality. This occurs due to the increased muscle tone and rigidity associated with the condition, which affects the normal functioning of the velopharyngeal mechanism. The heightened tone can lead to difficulty in fully closing the velopharyngeal port, resulting in an excessive amount of airflow through the nasal passages during the production of speech sounds. This causes the speech to have a nasal quality that is a hallmark of hypernasality.

Understanding this characteristic is essential as it helps in differentiating spastic dysarthria from other types of dysarthria, such as flaccid dysarthria, which may present differently in terms of resonance due to the underlying neural and muscular issues affecting speech production.