Sound production treatment: effects of blocked and random practice

Update on Identification and Treatment of Infants and Toddlers With Suspected Childhood Apraxia of Speech

PURPOSE

The purpose of this tutorial is to (a) provide an updated review of the literature pertaining to proposed early features of childhood apraxia of speech (CAS), (b) discuss the findings of recent treatment studies of infants and toddlers with suspected CAS (sCAS), and (c) present evidence-based strategies and tools that can be used for the identification of and intervention for infants and toddlers with sCAS or at high risk for the disorder.

METHOD

Since Davis and Velleman's (2000) seminal work on assessment and intervention in infants and toddlers with sCAS, limited research has guided clinicians in the complex task of identifying and treating early speech motor difficulties prior to a definitive diagnosis of CAS. Following the structure of Davis and Velleman, we explore the proposed early characteristics of CAS with reference to contemporary research. Next, we describe the limited treatment studies that have investigated intervention for infants and toddlers at risk of or suspected of having CAS. Finally, we present practical suggestions for integrating this knowledge into clinical practice.

CONCLUSIONS

Many of the originally proposed correlates of CAS in infants and toddlers now have research supporting their presence. However, questions remain about the developmental trajectory of the disorder. Although limited in number and restricted by lack of experimental control, emerging treatment studies can help guide clinicians in providing appropriate intervention to infants and toddlers with sCAS who need not wait for a definitive diagnosis to initiate intervention.

The Outcomes of Remote Administration of Combined Aphasia and Apraxia of Speech Treatment: A Single-Subject Experimental Design Study

PURPOSE

This study was designed to examine the outcomes of Combined Aphasia and Apraxia of Speech Treatment (CAAST) administered remotely in terms of acquisition and generalization effects and to compare these effects to previous in-person CAAST studies and Response Elaboration Training (RET)/Modified-Response Elaboration Training (M-RET) benchmarks.

METHOD

Multiple probe designs across participants and behaviors were employed with three speakers with chronic aphasia and apraxia of speech. Correct information units (CIUs) were the primary outcome measure to measure changes in language production. Percent consonants correct (PCC) was used as the secondary outcome measure to evaluate changes in speech sound accuracy. Production of CIUs was compared with existing benchmarks from Bunker et al.'s (2019) meta-analysis of previous RET/M-RET studies. In addition, both CIUs and PCC were compared with the most recent CAAST in-person studies.

RESULTS

All participants demonstrated substantial increases in CIUs for treated and untreated picture sets, comparable to outcomes of in-person CAAST administration. These language changes were maintained at posttreatment intervals for all participants. PCC also improved for all participants, with gains in articulatory accuracy being maintained posttreatment.

CONCLUSIONS

Improvements in CIU production and PCC for all three participants were in keeping with results from Wambaugh et al. (2017). These findings provide additional support for the efficacy of CAAST and indicate that remote administration may be a viable alternative to in-person application.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.23418635.

The Impact of Telehealth on the Efficacy of Sound Production Treatment

PURPOSE

This investigation was designed to systematically examine the acquisition, maintenance, and response generalization effects of Sound Production Treatment (SPT) delivered via telehealth in comparison to existing in-person outcomes for SPT.

METHOD

A multiple-baseline design across behaviors and participants was used with two individuals with chronic apraxia of speech (AOS) and aphasia. Accuracy of target speech sounds in treated and untreated words within phrases served as the dependent variable.

RESULTS

Both participants demonstrated positive gains for treatment and generalization items. Participant 1 demonstrated gains for both sets of treatment items with the application of treatment, but production accuracy at 2 and 6 weeks posttreatment was inconsistent. Participant 2 demonstrated large gains for both sets of treatment items with good maintenance at 2 and 6 weeks posttreatment. Effect sizes for both participants were similar to the traditional (in-person) SPT effect size benchmarks.

CONCLUSIONS

The positive outcomes from this study indicate that individuals with AOS can benefit from SPT delivered via telehealth. These findings warrant further research examining the effects of SPT through telehealth and should include individuals with AOS with varying severity. This investigation serves as the first telehealth study to systematically examine treatment outcomes for SPT.

Reproducibility in Small-N Treatment Research: A Tutorial Using Examples From Aphasiology

PURPOSE

Small-N studies are the dominant study design supporting evidence-based interventions in communication science and disorders, including treatments for aphasia and related disorders. However, there is little guidance for conducting reproducible analyses or selecting appropriate effect sizes in small-N studies, which has implications for scientific review, rigor, and replication. This tutorial aims to (a) demonstrate how to conduct reproducible analyses using effect sizes common to research in aphasia and related disorders and (b) provide a conceptual discussion to improve the reader's understanding of these effect sizes.

METHOD

We provide a tutorial on reproducible analyses of small-N designs in the statistical programming language R using published data from Wambaugh et al. (2017). In addition, we discuss the strengths, weaknesses, reporting requirements, and impact of experimental design decisions on effect sizes common to this body of research.

RESULTS

Reproducible code demonstrates implementation and comparison of within-case standardized mean difference, proportion of maximal gain, tau-U, and frequentist and Bayesian mixed-effects models. Data, code, and an interactive web application are available as a resource for researchers, clinicians, and students.

CONCLUSIONS

Pursuing reproducible research is key to promoting transparency in small-N treatment research. Researchers and clinicians must understand the properties of common effect size measures to make informed decisions in order to select ideal effect size measures and act as informed consumers of small-N studies. Together, a commitment to reproducibility and a keen understanding of effect sizes can improve the scientific rigor and synthesis of the evidence supporting clinical services in aphasiology and in communication sciences and disorders more broadly. Supplemental Material and Open Science Form: https://doi.org/10.23641/asha.21699476.

A randomized crossover single-case series comparing blocked versus random treatment for anomia

The motor learning literature has demonstrated that blocked practice facilitates better acquisition of motor skills, whereas random practice facilitates retention and transfer. The verbal learning and memory literature offers similar evidence. The purpose of this study was to investigate effects of blocked versus random practice in treatment for anomia. The study used a single site, randomized crossover design, with two replicated experimental phases (two blocked and two random) for each of 10 individuals with anomia. Each phase consisted of a cued picture-naming treatment. Individual treatment and maintenance effects, as well as weighted averages and group effects, were calculated using Tau-U based on the proportion of correctly named probes. Nine of 10 participants demonstrated treatment effects during each of the four phases. Acquisition was comparable for blocked and random practice. Maintenance effects were observed following seven blocked phases of treatment and 12 random phases of treatment across participants. For four of 10 participants the random schedule resulted in better maintenance of trained items. Although further research is needed, the present data suggest that for word retrieval treatment with multiple repetitions of the same items, a random presentation may benefit maintenance of treatment gains.

Speech Therapy Interventions for Acquired Apraxia of Speech: An Updated Systematic Review

PURPOSE

This systematic review aims to summarize and evaluate the available literature on speech and language therapy interventions for acquired apraxia of speech since 2012.

METHOD

A systematic search in six electronic databases was performed from 2013 to 2020. The following primary outcomes were summarized: (a) improvement in targeted behaviors, (b) generalization, and (c) maintenance of outcomes. Moreover, studies were evaluated for the level of evidence and the clinical phase.

RESULTS

Of the 3,070 records identified, 27 studies were included in this review. The majority of the studies (n = 22) used articulatory kinematic approaches followed by intersystemic facilitation/reorganization treatments (n = 4) and other approaches (n = 1). According to the classes defined in Clinical Practice Guideline Process Manual (Gronseth et al., 2017), one was Class II, 10 were Class III, 10 were Class III-b (fulfill Class III criteria except for independence of assessors' criterion), and five were Class IV. In terms of clinical phase, one study classified as Phase III, 10 as Phase II, and 15 as Phase I.

CONCLUSIONS

Among the interventions for apraxia of speech, articulatory kinematic treatments have become prominent over the last 8 years. Focusing on self-administrated therapies, use of technology for therapy administration and development of treatments that focus on apraxia of speech and aphasia simultaneously were identified as new advancements in the apraxia of speech literature. The methodological quality, clinical phase, and level of evidence of the studies have improved within the past 8 years. Large-scale randomized controlled trials for articulatory kinematic approaches and future studies on other treatment approaches are warranted.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.22223785.

Behavioral interventions for poststroke aphasia

There is a long history of behavioral interventions for poststroke aphasia with hundreds of studies supporting the benefits of aphasia treatment. However, interventions for aphasia are complex with many interacting components, and no one treatment is appropriate for all persons with aphasia. We present a novel, simple framework for classifying aphasia interventions. The framework is incorporated within the overarching International Classification of Functioning, Disability, and Health (ICF) model and is consistent with the commonly-held definition that aphasia is a multimodality disorder that impairs, in varying degrees, the understanding and expression of both oral and written language modalities. Furthermore, within the language impairment level, it distinguishes between the linguistic areas of phonology, semantics, and syntax that may be impaired individually or in combination. We define the terminology of the proposed framework and then categorize some common examples of behavioral interventions for post-stroke aphasia. We describe some of these interventions in greater detail to illustrate the extensive toolbox of evidence-based treatments for aphasia. We address some key issues that clinicians, usually speech-language pathologists, consider when selecting interventions for their specific patients with aphasia, including dose. Finally, we address various models of service delivery for persons with aphasia such as Intensive Comprehensive Aphasia Programs (ICAPs) and Aphasia Centers.

Use of ultrasound visual feedback in speech intervention for children with cochlear implants

The purpose of the present study was to evaluate the efficacy of ultrasound visual feedback in speech intervention for young children with cochlear implants. Although ultrasound technology has been used for intervention in children with speech sound disorders, there is little systematic evidence regarding relative efficacy of ultrasound visual feedback for young children with cochlear implants. Two children with cochlear implants participated in this study. The children's articulation was tested using Goldman-Fristoe Test of Articulation-2 and probes. Therapy was provided semi-weekly for 30-minute sessions over the course of nine to 10 weeks. Visual inspection showed an increasing trend in production accuracy to the criterion accuracy of 80% for target sounds. Maintenance of skills were observed at two weeks and two months post-intervention. The results of this study indicated that ultrasound visual feedback is likely an effective intervention tool for treating speech sound disorders in children with cochlear implants. Future studies including a larger sample size should be conducted to verify these findings.

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.

Acquired Apraxia of Speech: Comparison of Electropalatography Treatment and Sound Production Treatment

Purpose This investigation compared 2 treatment approaches for acquired apraxia of speech. The effects of a treatment that uses an articulatory-kinematic approach in conjunction with visual biofeedback (VBFB) via electropalatography (EPG) were compared to Sound Production Treatment (SPT), an established behavioral treatment that is also an articulatory-kinematic approach. Method A multiple baseline design across behaviors and participants was used with 2 participants with chronic apraxia of speech and aphasia. Accuracy of target speech sounds in treated and untreated words or phrases in probe sessions served as the dependent variable. The effects of 2 treatments based on an articulatory-kinematic approach were compared: (a) VBFB via EPG and (b) SPT. The order of treatments was counterbalanced across participants. Results Positive changes in articulatory accuracy were observed for SPT and VBFB treatment via EPG. Generalization to untreated stimulus items composed of treated speech sounds was also positive for both treatments. However, participants achieved greater articulatory accuracy with SPT during treatment and better long-term maintenance. Discussion Both treatment approaches resulted in improved speech production accuracy, but gains were greater for SPT. However, further research with additional participants is needed due to the small sample size included in this investigation.

Perceptual Characteristics of Consonant Production in Apraxia of Speech and Aphasia

Purpose This retrospective analysis examined group differences in error rate across 4 contextual variables (clusters vs. singletons, syllable position, number of syllables, and articulatory phonetic features) in adults with apraxia of speech (AOS) and adults with aphasia only. Group differences in the distribution of error type across contextual variables were also examined. Method Ten individuals with acquired AOS and aphasia and 11 individuals with aphasia participated in this study. In the context of a 2-group experimental design, the influence of 4 contextual variables on error rate and error type distribution was examined via repetition of 29 multisyllabic words. Error rates were analyzed using Bayesian methods, whereas distribution of error type was examined via descriptive statistics. Results There were 4 findings of robust differences between the 2 groups. These differences were found for syllable position, number of syllables, manner of articulation, and voicing. Group differences were less robust for clusters versus singletons and place of articulation. Results of error type distribution show a high proportion of distortion and substitution errors in speakers with AOS and a high proportion of substitution and omission errors in speakers with aphasia. Conclusion Findings add to the continued effort to improve the understanding and assessment of AOS and aphasia. Several contextual variables more consistently influenced breakdown in participants with AOS compared to participants with aphasia and should be considered during the diagnostic process. Supplemental Material https://doi.org/10.23641/asha.9701690.

Investigation of Feedback Schedules on Speech Motor Learning in Older Adults

BACKGROUND

The principles of motor learning (PML) emerged from studies of limb motor skills in healthy, young adults. The applicability of these principles to speech motor learning, and to older adults, is uncertain.

AIMS

The purpose of this study was to examine one PML, feedback frequency, and its effect on retention and generalization of a novel speech and comparable tracing task.

METHODS

Sixty older adults completed a speech motor learning task requiring the production of a novel phrase at speaking rates 2 times and 3 times slower than habitual rate. Participants also completed a limb motor learning task requiring the tracing of a sine wave 2x and 3x slower than habitual rate. Participants were randomly assigned to receive feedback every trial, every 5th trial, or every 10th trial. Mean absolute error was measured to examine immediate generalization, delayed generalization, and 2-day retention.

FINDINGS

Results suggested that feedback frequency did not have an effect on the retention and generalization of the speech or manual task, supporting the small but growing literature highlighting the constraints of generalizing the PML to other modalities and populations.

Combined aphasia and apraxia of speech treatment (CAAST): Systematic replications in the development of a novel treatment

PURPOSE

The purpose of this investigation was to examine the effects of a modified version of a newly developed therapy for aphasia and acquired apraxia of speech (AOS), Combined Aphasia and Apraxia of Speech Treatment (CAAST).

METHOD

Four speakers with chronic AOS and aphasia received CAAST in the context of multiple baseline designs. Dependent variables included language measures (i.e. production of correct information units (CIUs)) and speech production measures (i.e. speech intelligibility and percent correct consonants (PCC) in sentence repetition).

RESULT

Three of the participants demonstrated improved CIU production with treated picture sets and two also demonstrated generalization to untreated sets. All participants achieved substantially increased CIU production in an untrained discourse context. Speech intelligibility increased for three of the participants and increases in PCC were observed for all of the participants at two weeks post-treatment. However, PCC improvements were maintained for only two of the speakers at six weeks post-treatment.

CONCLUSION

The revised CAAST protocol was associated with improved changes in speech and generalization across contexts in comparison to the previous iteration of CAAST. However, focus on sentence production in generalization practice may have been detrimental to CIU production for one participant.

Effects of Blocked and Random Practice Schedule on Outcomes of Sound Production Treatment for Acquired Apraxia of Speech: Results of a Group Investigation

PURPOSE

The purpose of this investigation was to compare the effects of schedule of practice (i.e., blocked vs. random) on outcomes of Sound Production Treatment (SPT; Wambaugh, Kalinyak-Fliszar, West, & Doyle, 1998) for speakers with chronic acquired apraxia of speech and aphasia.

METHOD

A combination of group and single-case experimental designs was used. Twenty participants each received SPT administered with randomized stimuli presentation (SPT-R) and SPT applied with blocked stimuli presentation (SPT-B). Treatment effects were examined with respect to accuracy of articulation as measured in treated and untreated experimental words produced during probes.

RESULTS

All participants demonstrated improved articulation of treated items with both practice schedules. Effect sizes were calculated to estimate magnitude of change for treated and untreated items by treatment condition. No significant differences were found for SPT-R and SPT-B relative to effect size. Percent change over the highest baseline performance was also calculated to provide a clinically relevant indication of improvement. Change scores associated with SPT-R were significantly higher than those for SPT-B for treated items but not untreated items.

CONCLUSION

SPT can result in improved articulation regardless of schedule of practice. However, SPT-R may result in greater gains for treated items.

SUPPLEMENTAL MATERIALS

https://doi.org/10.23641/asha.5116831.

Identification and Remediation of Phonological and Motor Errors in Acquired Sound Production Impairment

Purpose

This study aimed to test whether an approach to distinguishing errors arising in phonological processing from those arising in motor planning also predicts the extent to which repetition-based training can lead to improved production of difficult sound sequences.

Method

Four individuals with acquired speech production impairment who produced consonant cluster errors involving deletion were examined using a repetition task. We compared the acoustic details of productions with deletion errors in target consonant clusters to singleton consonants. Changes in accuracy over the course of the study were also compared.

Results

Two individuals produced deletion errors consistent with a phonological locus of the errors, and 2 individuals produced errors consistent with a motoric locus of the errors. The 2 individuals who made phonologically driven errors showed no change in performance on a repetition training task, whereas the 2 individuals with motoric errors improved in their production of both trained and untrained items.

Conclusions

The results extend previous findings about a metric for identifying the source of sound production errors in individuals with both apraxia of speech and aphasia. In particular, this work may provide a tool for identifying predominant error types in individuals with complex deficits.

The Use of Electropalatography in the Treatment of Acquired Apraxia of Speech

PURPOSE

This investigation was designed to examine the effects of an articulatory-kinematic treatment in conjunction with visual biofeedback (VBFB) via electropalatography (EPG) on the accuracy of articulation for acquired apraxia of speech (AOS).

METHOD

A multiple-baseline design across participants and behaviors was used with 4 individuals with chronic AOS and aphasia. Accuracy of target speech sounds in treated and untreated phrases in probe sessions served as the dependent variable. Participants received an articulatory-kinematic treatment in combination with VBFB, which was sequentially applied to 3 stimulus sets composed of 2-word phrases with a target speech sound for each set.

RESULTS

Positive changes in articulatory accuracy were observed for participants for the majority of treated speech sounds. Also, there was generalization to untreated phrases for most trained speech sounds. Two participants had better long-term maintenance of treated speech sounds in both trained and untrained stimuli.

CONCLUSIONS

Findings indicate EPG may be a potential treatment tool for AOS. It appears that individuals with AOS can benefit from VBFB via EPG in improving articulatory accuracy. However, further research is needed to determine if VBFB is more advantageous than behavioral treatments that have been proven effective in improving speech production for speakers with AOS.

Sound production treatment for acquired apraxia of speech: Effects of blocked and random practice on multisyllabic word production

PURPOSE

This study was designed to examine the effects of practice schedule, blocked vs random, on outcomes of a behavioural treatment for acquired apraxia of speech (AOS), Sound Production Treatment (SPT).

METHOD

SPT was administered to four speakers with chronic AOS and aphasia in the context of multiple baseline designs across behaviours and participants. Treatment was applied to multiple sound errors within three-to-five syllable words. All participants received both practice schedules: SPT-Random (SPT-R) and SPT-Blocked (SPT-B).

RESULT

Improvements in accuracy of word production for trained items were found for both treatment conditions for all participants. One participant demonstrated better maintenance effects associated with SPT-R. Response generalisation to untreated words varied across participants, but was generally modest and unstable. Stimulus generalisation to production of words in sentence completion was positive for three of the participants. Stimulus generalisation to production of phrases was positive for two of the participants.

CONCLUSION

Findings provide additional efficacy data regarding SPT's effects on articulation of treated items and extend knowledge of the treatment's effects when applied to multiple targets within multisyllabic words.

Consolidating behavioral and neurophysiologic findings to explain the influence of contextual interference during motor sequence learning

Motor sequence learning under high levels of contextual interference (CI) disrupts initial performance but supports delayed test and transfer performance when compared to learning under low CI. Integrating findings from early behavioral work and more recent experimental efforts that incorporated neurophysiologic measures led to a novel account of the role of CI during motor sequence learning. This account focuses on important contributions from two neural regions-the dorsal premotor area and the SMA complex-that are recruited earlier and more extensively during the planning of a motor sequence in a high CI context. It is proposed that activation of these regions is critical to early adaptation of sequence structure amenable to long-term storage. Moreover, greater CI enhances access to newly acquired motor sequence knowledge through (1) the emergence of temporary functional connectivity between neural sites previously described as crucial to successful long-term performance of sequential behaviors, and (2) heightened excitability of M1-a key constituent of the temporary coupled neural circuits, and the primary candidate for storage of motor memory.

Sound Production Treatment: Synthesis and Quantification of Outcomes

PURPOSE

This investigation was designed to provide a quantification and synthesis of a series of single-case experimental design investigations into the effects of sound production treatment, an articulatory-kinematic treatment for acquired apraxia of speech (AOS). The main purpose was to perform a meta-analysis of aggregated sound production treatment data in order to provide benchmarks to serve as indicators of magnitude of change. Additional analyses explored various factors influencing effect sizes and level of performance.

METHOD

Effect sizes were calculated for treated and untreated items for 24 participants across 10 investigations. Benchmarks were calculated as the quartiles of the distributions of the effect sizes. Correlational analyses were performed to examine (a) end-of-treatment performance relative to follow-up performance, (b) response of trained items relative to untrained items, and (c) effect size relative to participant variables.

RESULTS

Effect sizes were predominantly large and positive; benchmarks for treated items were larger than those for untreated items. End of treatment and follow-up performance were positively correlated, and response generalization was positively correlated with AOS severity.

CONCLUSION

These benchmarks may assist in evaluating the effects of interventions for individuals with AOS utilizing similar outcome measures in both clinical and research settings.

The Application of Motor Learning Concepts to the Treatment of Children with Compensatory Speech Sound Errors

Children with cleft palate frequently present with compensatory speech sound errors, which are generally targeted in treatment. Often, treatment consists of different phonetic teaching methods and procedures that are delivered via an operant learning paradigm; however, there are other theoretical models of learning that may prove more efficacious for modifying compensatory errors. Motor learning is a teaching/learning methodology that has an extensive body of research to support its use in the acquisition and development of motor skills. Currently, researchers are using motor learning paradigms in the treatment of different speech disorders and evidence on efficacy is being collected. This paper will discuss motor learning as a methodology for treating compensatory speech sound errors in an effective and efficient manner.