Which dysarthria subtype is characterized by hypernasality and nasal emissions?

Flaccid dysarthria is characterized by muscle weakness and decreased tone, which often leads to a notable speech impairment that includes hypernasality and nasal emissions. This occurs because the weakness in the muscles responsible for closing off the nasal passages during speech can prevent proper airflow, resulting in excessive nasal resonance.

In flaccid dysarthria, the impact of lower motor neuron damage on the articulatory muscles can also cause articulatory imprecision, further affecting speech clarity. Hypernasality is particularly prominent due to the inability of the velopharyngeal mechanism to adequately seal off the nasal cavity. Thus, the combination of muscle weakness and the inability to effectively control airflow through the nasal passages is central to understanding why this subtype presents with hypernasality and nasal emissions.

Other types of dysarthria, such as spastic, ataxic, or hyperkinetic, present with different characteristics and do not primarily exhibit the hypernasality associated with flaccid dysarthria. For example, spastic dysarthria typically features a strained-strangled voice quality and may not involve significant nasal emissions. This distinction helps in accurately diagnosing and tailoring treatment approaches for individuals with differing types of dysarthria.