Effects of Practice Variability on Learning of Relaxed Phonation in Vocally Hyperfunctional Speakers

Abstract

The present study investigated the effects of practice variability on the learning of relaxed phonation using a motor learning perspective. Twenty-one individuals with hyperfunctional voice problems were evenly and randomly assigned to three groups of practice conditions: constant, blocked, and random practice conditions. During training, participants in the constant practice condition were asked to read aloud sentence stimuli with four Chinese characters. Participants in the blocked practice condition were asked to read aloud sentence stimuli with increasing sentence length, starting from sets of two characters to five characters. Participants in the random practice condition were asked to practice reading sentence stimuli of variable length from two to five characters presented in a random fashion. Surface electromyographic feedback (sEMG) from the thyrohyoid muscle site was given to each participant after reading every two sentence stimuli. Results demonstrated that for all the participants, voice motor learning was evidenced by the decreased sEMG levels in delayed retention test. Generalization to untrained passage was shown as well. However, results did not reveal any difference in the learning among the three practice conditions. The findings from the present study did not support the hypothesis of contextual interference, which states that practice using variable items presented in a random mode is more beneficial to learning than practice using constant items.

Motor-Based Intervention Protocols in Treatment of Childhood Apraxia of Speech (CAS)

“…Although some studies reported findings consistent with the motor learning literature [14••,41,47], others failed to find clear and consistent differences between conditions [42,43,45,51,52], or reported opposite effects for some participants [22•,44]. It is likely that differences in tasks, measures, and populations contribute to this mixed pattern.…”

“…For individuals with speech/voice impairments, studies have examined practice amount [14••], practice schedule [22•,41,42], practice variability [43], practice distribution (massed vs. distributed) [42,44,45], feedback type (verbal knowledge of results vs. biofeedback knowledge of performance) [46], feedback frequency [21,47–51], feedback timing (immediate vs. delayed) [48] and attentional focus [52]. Although some studies reported findings consistent with the motor learning literature [14••,41,47], others failed to find clear and consistent differences between conditions [42,43,45,51,52], or reported opposite effects for some participants [22•,44].…”

Ultrasound Visual Feedback Treatment and Practice Variability for Residual Speech Sound Errors

“…In speech-related research, Ballard, Maas, and Robin (2007) observed positive treatment effects when including variable practice for adults with acquired apraxia of speech. Studies that have directly compared constant vs. variable practice in speech treatment have found mixed results; Wong, Ma and Yiu (2011) reported no advantage for practice variability among individuals with hyperfunctional voice problems but Adams and Page (2000) observed an advantage for variable practice in motor speech learning in healthy adults. However, there is no systematic exploration of this principle of practice variability among speech motor learning in individuals with RSSEs.…”

Is There an Interaction between Task Complexity and Practice Variability in Speech-Motor learning?

“…However, role of PMLs in speech-motor learning [8][9][10][11][12][13][14] . An aspect of PMLs to have gained considerable attention in speechmotor learning is practice variability [8,15,16] . Practice variability can range from practicing just one variant of a motor skill (constant practice) to practicing 2 or more variants of the same motor skill (variable practice).…”