Due to lesions in the basal ganglia, individuals with PD may experience hypokinetic dysarthria
, a term that describes a group of speech characteristics pertaining to phonation and respiration; articulation; prosody; and resonance (Pinto et al., 2004).
Ratings indicated abnormally low tone, but only for a single task, for two participants in the flaccid group (unilateral), three in the flaccid-spastic group (bilateral), and one in the hypokinetic dysarthria group (bilateral).
Tissue stiffness values tended to be higher in individuals with flaccid dysarthria than in those with spastic or hypokinetic dysarthria. For example, Figure 2 illustrates actual stiffness measures obtained from the superior surface of the tongue, as well as predicted values based on diagnostic criteria for the various dysarthrias and what is known of their neurological underpinnings.
All participants were diagnosed with hypokinetic dysarthria
, which is consistent with the speech profile generally observed in people with PD .
At present, speech therapy programs for patients with PD who exhibit hypokinetic dysarthria
mainly target vocal loudness, following the Lee Silverman Voice Treatment (LSVT) protocol (Ramig, Countryman, Thompson, & Horii, 1995; Ramig, Pawlas, & Countryman, 1995).
The typical pattern of hypokinetic dysarthria
is characterized by a breathy or hoarse voice, reduced loudness and restricted pitch variability (monopitch and monoloudness), imprecise articulation and abnormalities of speech rate, and pause ratio (e.g., [7-9]).
in Parkinson's disease (PD) is a motor speech disorder that arises as a consequence of a neurodegenerative process.