Lingual kinematic strategies used to increase speech rate: Comparison between younger and older adults

Kinematic analysis of articulatory coupling in acquired apraxia of speech post-stroke

“…Results indicated that 87.5% of the participants achieved a faster rate of speech by reducing the total distance travelled by the tongue; two of these participants also evidenced a reduction in maximum velocity and one participant evidenced an increase in maximum velocity and subsequently maximum acceleration [27]. In a follow-up study, Goozée et al [28] reported that both younger and older adults appear to increase syllable repetition rate by reducing the distance travelled by the tongue. The impact of rate on jaw and constrictor (i.e.…”

“…A reduction in movement amplitude has been found to have a destabilizing effect on the speech mechanism [28,44,45] and therefore the participants with AOS might have employed larger articulatory movements in an effort to increase tongue and/or jaw stability, at the risk of being less efficient.…”

“…This would be considered a reactive strategy (i.e. requires less articulatory effort) and is comparable to that generally employed by healthy talkers [27,28].…”

“…covariance reflects the standard deviation of articulator movement, in addition to the zerolag correlation), the aforementioned observation could also imply that A1 relied on more expansive articulatory movement to generate a faster rate of speech. This would be considered an active strategy to increase syllable repetition rate that would require increased articulatory effort [28].…”

“…It was hypothesized that the participants with AOS would exhibit increased spatiotemporal coupling between individual articulators, to reflect a reduction in functional movement independence. An increase in speech rate was anticipated to result in weaker coupling, given that a fast rate of speech can be associated with a reduction in articulatory displacement [27][28][29].…”