Effects of practice schedules on speech motor learning

A Nonrandomized Trial for Student Teachers of an In-Person and Telepractice Global Voice Prevention and Therapy Model With Estill Voice Training Assessed by the VoiceEvalU8 App

Purpose This study investigated the effects of the in-person and telepractice Global Voice Prevention and Therapy Model (GVPTM) treatment conditions and a control condition with vocally healthy student teachers. Method In this single-blinded, nonrandomized trial, 82 participants completed all aspects of the study. Estill Voice Training was used as the stimulability component of the GVPTM to train multiple new voices meeting all the vocal needs of the student teachers. Outcomes were assessed using acoustic, perceptual, and aerodynamic measures captured by the VoiceEvalU8 app at pre and post in fall and during student teaching in spring. Results Significant improvements were achieved for several acoustic and perceptual measures in the treatment conditions, but not in the control condition. The in-person and telepractice conditions produced similar results. The all-voiced phrase and connected speech were more successful in demonstrating voice change for some of the perturbation measures as compared to sustained /a/. Conclusions The treatment conditions were successful in improving the participants' voices for fundamental frequency and some acoustic perturbation measures while maintaining the improvements during student teaching. In addition, the treatment conditions were successful in decreasing the negative impact of voice-related quality of life and vocal fatigue during student teaching. Future research should address the effectiveness of the various components of the GVPTM, the application of the GVPTM with patients with voice disorders, the relevance of defining auditory-perceptual terms by the anatomy and physiology of the voice production system (i.e., Estill Voice Training), and the continued use of the VoiceEvalU8 app for clinical voice investigations. Supplemental Material https://doi.org/10.23641/asha.13626824.

Sound Production Treatment for Acquired Apraxia of Speech: An Examination of Dosage in Relation to Probe Performance

Purpose This study was designed to examine the association of dosage and effects of Sound Production Treatment (SPT) for acquired apraxia of speech. Method Treatment logs and probe data from 20 speakers with apraxia of speech and aphasia were submitted to a retrospective analysis. The number of treatment sessions and teaching episodes was examined relative to (a) change in articulation accuracy above baseline performance, (b) mastery of production, and (c) maintenance. The impact of practice schedule (SPT-Blocked vs. SPT-Random) was also examined. Results The average number of treatment sessions conducted prior to change was 5.4 for SPT-Blocked and 3.9 for SPT-Random. The mean number of teaching episodes preceding change was 334 for SPT-Blocked and 179 for SPT-Random. Mastery occurred within an average of 13.7 sessions (1,252 teaching episodes) and 12.4 sessions (1,082 teaching episodes) for SPT-Blocked and SPT-Random, respectively. Comparisons of dosage metric values across practice schedules did not reveal substantial differences. Significant negative correlations were found between follow-up probe performance and the dosage metrics. Conclusions Only a few treatment sessions were needed to achieve initial positive changes in articulation, with mastery occurring within 12-14 sessions for the majority of participants. Earlier occurrence of change or mastery was associated with better follow-up performance. Supplemental Material https://doi.org/10.23641/asha.12592190.

Dissimilar Phonemes Create a Contextual Interference Effect During a Nonword Repetition Task

Purpose: The contextual interference effect is a motor learning phenomenon where conditions that decrease overall learning during practice enhance overall learning with new tasks. In the limb literature, this effect is observed when different practice conditions are used (e.g., blocked vs. random practice schedules). In speech motor learning, contextual interference effects are mixed. The differences observed during speech motor learning may be due to the stimuli used. We hypothesized that dissimilar phonemes might create interference during speech motor learning, such that training accuracy would decrease. However, generalization accuracy would increase compared to practice with nonwords containing similar phonemes.

Method: Thirty young adults with typical speech and hearing participated in a motor learning study using a cross-over design. Participants engaged in nonword repetition training followed by an immediate retention and transfer task with two sets of nonwords: nonwords with similar phonemes and nonwords with dissimilar phonemes. Percent consonants correct were calculated to examine the effects of the two different types of nonwords based on the stage of skill acquisition.

Results: A contextual interference effect was observed in this study using nonwords that varied in phonemic similarity. Nonwords with similar phonemes were produced with greater accuracy during the training stage of skill acquisition, and nonwords with dissimilar phonemes were produced with greater accuracy during the transfer stage.

Conclusion: The proposed hypothesis for this study was met – practicing nonwords with dissimilar phonemes resulted in greater accuracy in the transfer phase of this experiment. Results indicate that phonemic dissimilarity produced contextual interference and influenced speech motor learning. These results indicate that the linguistic properties of stimuli must be factored into speech motor learning. Future research should explore if other linguistic variables interact with variables of motor learning to enhance speech practice and generalization outcomes.

Consistent Symbol Location Affects Motor Learning in Preschoolers Without Disabilities: Implications for Designing Augmentative and Alternative Communication Displays

PURPOSE

Designing augmentative and alternative communication (AAC) displays that minimize operational demands is an important aspect of AAC intervention. The current study compared the effect of 2 display designs on the speed of locating target words by preschoolers without disabilities.

METHOD

Across 5 sessions, participants in the consistent condition (n = 12) were asked to locate symbols on arrays that did not change, whereas participants in the variable condition (n = 12) utilized arrays where the symbols changed locations each session.

RESULTS

No difference in response time across conditions was noted during the 1st session; however, by the 5th session, participants in the consistent condition demonstrated significantly faster response times than participants in the variable condition.

CONCLUSIONS

The current study illustrated an advantage of consistent symbol location for preschoolers without disabilities. Clinical applications for incorporating consistent symbol location into AAC display design are discussed; however, replication with children who use AAC is critical.

Role of Constant, Random and Blocked Practice in an Electromyography-Based Oral Motor Learning Task

PURPOSE

The role of principles of motor learning (PMLs) in speech has received much attention in the past decade. Oral motor learning, however, has not received similar consideration. This study evaluated the role of three practice conditions in an oral motor tracking task.

METHOD

Forty-five healthy adult participants were randomly and equally assigned to one of three practice conditions (constant, blocked, and random) and participated in an electromyography-based task. The study consisted of four sessions, at one session a day for four consecutive days. The first three days sessions included a practice phase, with immediate visual feedback, and an immediate retention phase, without visual feedback. The fourth session did not include practice, but only delayed retention testing, lasting 10-15 minutes, without visual feedback.

RESULTS

Random group participants performed better than participants in constant and blocked practice conditions on all the four days. Constant group participants demonstrated superior learning over blocked group participants only on day 4.

CONCLUSION

Findings indicate that random practice facilitates oral motor learning, which is in line with limb/speech motor learning literature. Future research should systematically investigate the outcomes of random practice as a function of different oral and speech-based tasks.

An Online Telepractice Model for the Prevention of Voice Disorders in Vocally Healthy Student Teachers Evaluated by a Smartphone Application

This article describes the Global Voice Prevention Model (GVPM) facilitated with student teachers at West Chester University and the VoiceEvalU8 smartphone application (app) used to assess the effectiveness of the GVPM. Twenty-one participants completed 1 of 3 conditions (i.e., in-person GVPM, telepractice GVPM, and control). The in-person and telepractice conditions ran for 4 weeks during fall 2016, with 1 week dedicated to vocal education and vocal hygiene and 3 weeks spent in vocal training. The control condition ran for 1 week and included only vocal education and vocal hygiene. The VoiceEvalU8 app was used at pre- and post-condition twice a day for 5 days to record acoustic, perceptual, and aerodynamic voice measures. The study is ongoing; therefore, preliminary acoustic results for fundamental frequency (F0) and jitter% are presented from pre- to post-condition. During spring 2017, the participants were student teaching and using the VoiceEvalU8 app to record the voice measures before and after teaching all day. A new group of participants will be enrolled fall 2017 for selection into 1 of the 3 conditions and then continue on to student teaching spring 2018.

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

BACKGROUND

Prior studies have investigated the influence of principles of motor learning (PMLs) on speech-motor learning. However, the interactive effect of different PMLs on speech-motor learning remains unknown.

PURPOSE

This study is aimed at investigating the interaction of 2 PMLs, that is, practice variability and task complexity and their influence on speech-motor learning.

METHOD

Forty healthy individuals (aged 18-30 years) were randomly and equally allocated to 2 groups where they had to either practice a simple (simple group) or a complex phrase (complex group). Two levels of practice variability (constant and variable) were considered in training participants in simple and complex groups. Participants practiced 50 practice trials of either complex or simple phrase during the first 2 days. At the end of training on each day, participants produced 10 trials of the phrase they practiced without feedback. On the third day, participants returned for a delayed retention test. The participant utterances on all the 3 days were recorded for later analysis.

RESULTS

Data analysis revealed that there was no major effect of practice condition, and there was no interaction of task complexity and practice condition. However, there was an interaction between data collection points and complexity.

CONCLUSION

The findings suggest that irrespective of the complexity of the to-be-learned speech task, there is no preponderance of variable over constant practice, which contradicts the findings of the non-speech-motor learning literature.

Effects of Blocked Versus Random Practice on Speech Motor Skill Acquisition and Retention

Purpose:

The effect of blocked practice (BP) versus random practice (RP) on the acquisition and retention of novel speech motor sequences in healthy young adults was examined.

Method:

Twenty participants underwent a comparable amount of practice in either blocked or random order and were tested for retention the following day. Behavioral accuracy and kinematic measures of timing were obtained.

Results:

Performance levels were significantly higher, overall, for the BP group compared with the RP during the acquisition phases. During the retention test, the RP group was significantly more accurate than the BP group. Similar trends were noted, but did not reach significance, for kinematic measures.

Conclusion:

Consistent with patterns established in the limb motor learning literature, our results indicate that BP leads to higher overall performance levels (though not necessarily greater gains in performance) during acquisition, whereas improved performance at retention is facilitated by RP.

Motor-based intervention protocols in treatment of childhood apraxia of speech (CAS)

This paper reviews current trends in treatment for childhood apraxia of speech (CAS), with a particular emphasis on motor-based intervention protocols. The paper first briefly discusses how CAS fits into the typology of speech sound disorders, followed by a discussion of the potential relevance of principles derived from the motor learning literature for CAS treatment. Next, different motor-based treatment protocols are reviewed, along with their evidence base. The paper concludes with a summary and discussion of future research needs.