Disordered rate of speech has been reported in some individuals with PD, and rapid rate or short rushes of speech have been reported in 6% to 13% of individuals with PD. Palilalia or stuttering-like speech disfluencies have been observed in a small percent of individuals with parkinsonism (30,31). The discrepant findings of speech rate in parkinsonian speech (slow vs. rapid) may be related to the presence or absence of compensatory mechanisms. Caliguiri (55) found, using kinematic analyses, that lip movements were normal when individuals with PD spoke at a rate of 3 to 5 syllable/sec, but hypokinetic when the rate increased to 5 to 7 syllable/sec, which is the typical rate of conversational speech. Similarly, Ackermann et al. (53) described a patient with akinetic-rigid PD who was instructed to synchronize labial DDK to sequences of periodic acoustic stimuli (2.5-6Hz). This individual was able to synchronize his DDK to the stimulus rate up to 4 Hz, but when the stimulus rate exceeded 4 Hz, his DDK was uncontrollably produced at 8 to 9 Hz, indicating speech hastening. These findings suggest that some patients may slow down their speech to prevent the tendency for the articulator to uncontrollably accelerate and deteriorate beyond a certain rate (65).
Was this article helpful?