Stability Over Time of Word Syllable Duration for Speakers With Acquired Apraxia of Speech.

PURPOSE: Neurogenic speech and language disorders-such as acquired apraxia of speech (AOS) and aphasia with phonemic paraphasia (APP)-are often misdiagnosed due to similarities in clinical presentation. Word syllable duration (WSD)-a measure of average syllable length in multisyllabic words-serves as a proxy for speech rate, which is an important and arguably more objective clinical characteristic of AOS and APP. This study reports stability of WSD over time for speakers with AOS (and aphasia). METHOD: Twenty-nine participants with AOS and aphasia (11 women and 18 men, Mage = 53.5 years, SD = 13.3) repeated 30 multisyllabic words (of three-, four-, and five-syllable lengths) on three occasions across 4 weeks. WSDs were calculated for each word and then averaged across each list (i.e., word length), as well as across combined lists (i.e., all 30 words) to yield four WSDs for each participant at each time point. Stability over time was calculated using Friedman's test for the group and using Spearman's rho for the individual level. Effects of time and word length were examined using robust mixed-effects linear regression. RESULTS: Friedman's tests and correlations indicated no significant difference in WSDs across sampling occasions for each word length separately or combined. WSD correlated positively with AOS severity and negatively with intelligibility but was not correlated with aphasia severity. Regression analyses confirmed WSD to be stable over time, while WSD calculated from only five tokens (i.e., WSD-5) was less stable over time. CONCLUSIONS: Results indicate that WSD can be a stable measure over time, at the individual and group level, providing support for its use in diagnosis and/or as an outcome measure, both clinically and for research. In general, WSD outperformed WSD-5, suggesting that it may be better to calculate WSD from more than five tokens. Stability of WSD in other populations and suitability for differential diagnosis need to be determined. Currently, differentiating disorders by speaking rate, alone, is not recommended. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.25438735.

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.

Stability of Speech Intelligibility Measures Over Repeated Sampling Times in Speakers With Acquired Apraxia of Speech.

Purpose The purpose of this investigation was to measure the test-retest stability of single-word intelligibility in a group of 28 speakers with chronic apraxia of speech and aphasia. Method The Assessment of Intelligibility of Dysarthric Speech was administered twice to each participant, with samples separated by 1 week. Scoring of recorded samples was completed independently by three expert listeners using transcription and multiple-choice scoring formats. Results Percent intelligible words was very similar for the group over the two sampling times for both scoring formats (i.e., within 1.5%), with no statistically significant differences found between times. Statistically significant, very strong, positive correlations were found between sampling times for intelligibility scores. Transcription and multiple-choice scores were strongly, positively correlated, with multiple-choice scores being statistically higher. There was a statistically significant difference between mean transcription and multiple-choice scores for the group at Time 1 and Time 2. Individual performance was similar to group performance for the majority of participants. Conclusions These findings indicate that single-word intelligibility measures are stable over repeated sampling occasions. Stability was evident for transcription and multiple-choice scoring methods. Supplemental Material https://doi.org/10.23641/asha.14226737.

Further Study of the Effects of Treatment Intensity on Outcomes of Sound Production Treatment for Acquired Apraxia of Speech: Does Dose Frequency Matter?

Purpose The aim of this study was to examine the effects of dose frequency, an aspect of treatment intensity, on articulation outcomes of sound production treatment (SPT). Method Twelve speakers with apraxia of speech and aphasia received SPT administered with an intense dose frequency and a nonintense/traditional dose frequency (SPT-T). Each participant received both treatment intensities in the context of multiple baseline designs across behaviors. SPT-Intense was provided for 3 hourly sessions per day/3 days per week; and SPT-T for 1 hour-long session per day/3 days per week. Twenty-seven treatment sessions were completed with each phase of treatment. Articulation accuracy was measured in probes of production of treated and untreated words. Results All participants achieved improved articulation of treated words with both intensities; there were no notable differences in magnitude of improvement associated with dose frequency. Positive response generalization to untrained words was found in 21 of 24 treatment applications; the cases of negligible response generalization occurred with SPT-T words. Conclusions Dose frequency (and corresponding total intervention duration) did not appear to impact treatment response for treated items. Disparate response generalization findings for 3 participants in the current study may relate to participant characteristics such as apraxia of speech severity and/or stimuli factors.

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.

Reliability and stability of the metrical stress effect on segmental production accuracy in persons with apraxia of speech.

BACKGROUND: Acquired apraxia of speech (AOS) involves speech-production deficits on both the segmental and suprasegmental levels. Recent research has identified a non-linear interaction between the metrical structure of bisyllabic words and word-production accuracy in German speakers with AOS, with trochaic words (strong-weak stress) being resistant to errors compared with iambic words (weak-strong). AIMS: To replicate previous findings in English speakers with AOS, to measure the test-retest reliability of the effect, and to examine the potential impact of different methods of word scoring. METHODS & PROCEDURES: Speech samples were collected from 27 speakers with AOS and aphasia. Participants were at least 12 months post-stroke or penetrating brain injury, and represented a large range of AOS and aphasia severities. Productions were elicited via verbal model. Sampling was conducted on three separate occasions: the initial data-collection session and then repeated samplings at 1- and 4-week intervals. Bisyllabic words with a CVCVC segmental structure were selected. The list was divided into sublists representing differing lexical stress patterns: A list of 42 trochees, and one of 37 iambs. All speech samples were phonetically transcribed and then aligned with canonical transcriptions via an edit distance algorithm that followed transcription alignment principles. Phonetic-level errors (distortions) were penalized less severely than phonemic-level errors. Per cent consonants correct and whole-word accuracy were also examined. Trochee and iamb lists were analysed separately. OUTCOMES & RESULTS: Paired samples t-tests indicated that the modified edit distance was significantly lower for the trochee lists than for the iamb lists. There was a lack of a significant effect of time on the absolute difference between modified edit distance for both lists. Intraclass coefficients suggested the list and procedures used are appropriate as an outcome measure for group research. CONCLUSIONS & IMPLICATIONS: The results suggest that in English, as in German, the trochaic structure is more resistant to segmental errors in persons with AOS and aphasia, providing replication of the findings of Aichert et al. in 2016. Further, this effect is stable over repeated sampling occasions. Implications for clinical management of AOS include possible ways to scaffold item difficulty and potentially improve stimulus generalization.

Interrater Reliability and Concurrent Validity for the Apraxia of Speech Rating Scale 3.0: Application With Persons With Acquired Apraxia of Speech and Aphasia.

Purpose This investigation was designed to provide interrater reliability data for the Apraxia of Speech Rating Scale 3.0 (ASRS 3.0; Strand, Duffy, Clark, & Josephs, 2014 ). Importantly, ratings were completed by investigators who were not involved with the ASRS development. Another aim was to evaluate the relationship of the ASRS 3.0 total score to word intelligibility. Method Two investigators independently completed ASRS 3.0 ratings for 28 participants with chronic apraxia of speech and aphasia. Intelligibility scores were obtained for all participants. Results Consistency of ratings for each feature and total score of the ASRS 3.0 was measured using intraclass correlation coefficients. Twelve of 13 intraclass correlation coefficients for feature ratings reached significance; clinical meaningfulness ranged from poor to excellent. Interrater reliability for the total scores was excellent. Similarly, absolute difference of ratings was minimal for the total scores, but varied across the 13 feature ratings. Correlations between the intelligibility scores and ASRS 3.0 total score were moderate to strong. Conclusion The total ASRS 3.0 score may be viewed as a reliable indicator of prevalence of apraxia of speech features. Although there was good to acceptable correspondence in ratings of the majority of the individual features, additional operationalization of rating procedures may be needed to improve interrater reliability for a few features.

Effects of Treatment Intensity on Outcomes in Acquired Apraxia of Speech.

Purpose: This investigation was designed to examine the effects of treatment intensity (i.e., dose frequency) on the outcomes of Sound Production Treatment (SPT) for acquired apraxia of speech. Method: Five men with chronic apraxia of speech and aphasia received both intense SPT (3 hr per day/3 days per week) and nonintense/traditional SPT (SPT-T; 1 hr per day/3 days per week) in the context of single-case experimental designs. Each treatment was applied separately to a designated set of experimental words with 1 treatment applied at a time. Twenty-seven treatment sessions were conducted with each phase of treatment. Accuracy of articulation of target sounds within treated and untreated experimental words was measured during the course of the investigation. Results: All participants demonstrated improved articulation with both treatment intensities. Better maintenance of gains for treated items was found with SPT-T for 2 participants as measured at an 8-week posttreatment retention probe. Superior maintenance of increased accuracy of production of untreated items was also observed with SPT-T for all participants. Conclusion: A less intense (distributed) application of SPT facilitated better maintenance of improved articulatory accuracy for untreated items, and in some cases treated items, than intense SPT. Supplemental Materials: https://doi.org/10.23641/asha.5734053.

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.

Acquired Apraxia of Speech: The Relationship Between Awareness of Errors in Word Productions and Treatment Outcomes.

PURPOSE: Awareness of errors has been considered a clinical feature of acquired apraxia of speech (AOS). However, there is limited research examining error awareness in speakers with AOS. The purpose of this investigation was to examine awareness of errors and explore the relationship between awareness of errors and treatment outcomes in speakers with AOS. METHOD: Twenty speakers with AOS and aphasia produced mono- and multisyllabic words in a repetition task. Following each production, speakers were asked to judge the accuracy of their production (i.e., correct or incorrect). Then, speakers received Sound Production Treatment. RESULTS: Judgment accuracy of productions for the group ranged from 20% to 96%. There was a weak relationship between judgment accuracy and probe performance at posttreatment (r = .47) and a moderate relationship between judgment accuracy and probe performance at follow-up (r = .53). CONCLUSION: Findings indicate that speakers with AOS varied in their ability to judge the accuracy of their productions. For some speakers, the ability to judge the accuracy of their productions did not coincide with their production accuracy of treatment stimuli at posttreatment and at follow-up. Further research is needed to explore the relationship between error awareness and treatment outcomes.

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.

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.

Self-Judgments of Word Production Accuracy in Acquired Apraxia of Speech.

Purpose: The ability to recognize one's own speech errors has long been considered a clinical feature of acquired apraxia of speech (AOS) despite limited empirical data supporting this notion. This study was designed to (a) investigate the ability of speakers with AOS to self-judge the accuracy of their own word productions and (b) examine the test-retest stability of a measure to quantify the self-judgments of speakers with AOS. Method: Twenty-four speakers with AOS and aphasia repeated mono- and multisyllabic words. After each word, they indicated whether their production was correct or incorrect. This procedure was repeated 1 week later to examine performance stability. Results: Percentage of incorrect word productions was stable for the group across times. Accuracy of judgments ranged from 64% to 100% at Time 1 and from 56% to 100% at Time 2. Inaccurate judgments of error productions (false positives) occurred much more frequently than inaccurate judgments of correct productions (false negatives). Conclusions: Error production was remarkably stable in our participants. As a group, the participants failed to detect almost one third of words produced erroneously. However, accuracy and stability of judgments over sampling times varied across participants. Findings suggest that error awareness might be a worthwhile target for treatment in some individuals 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.

Treatment for Acquired Apraxia of Speech: A Systematic Review of Intervention Research Between 2004 and 2012.

OBJECTIVES: The aim was for the appointed committee of the Academy of Neurological Communication Disorders and Sciences to conduct a systematic review of published intervention studies of acquired apraxia of speech (AOS), updating the previous committee's review article from 2006. METHOD: A systematic search of 11 databases identified 215 articles, with 26 meeting inclusion criteria of (a) stating intention to measure effects of treatment on AOS and (b) data representing treatment effects for at least 1 individual stated to have AOS. RESULTS: All studies involved within-participant experimental designs, with sample sizes of 1 to 44 (median = 1). Confidence in diagnosis was rated high to reasonable in 18 of 26 studies. Most studies (24/26) reported on articulatory-kinematic approaches; 2 applied rhythm/rate control methods. Six studies had sufficient experimental control for Class III rating according to the Clinical Practice Guidelines Process Manual (American Academy of Neurology, 2011), with 15 others satisfying all criteria for Class III except use of independent or objective outcome measurement. CONCLUSIONS: The most important global clinical conclusion from this review is that the weight of evidence supports a strong effect for both articulatory-kinematic and rate/rhythm approaches to AOS treatment. The quantity of work, experimental rigor, and reporting of diagnostic criteria continue to improve and strengthen confidence in the corpus of research.

Combined Aphasia and Apraxia of Speech Treatment (CAAST): effects of a novel therapy.

PURPOSE: This investigation was designed to examine the effects of a newly developed treatment for aphasia and acquired apraxia of speech (AOS). Combined Aphasia and Apraxia of Speech Treatment (CAAST) targets language and speech production simultaneously, with treatment techniques derived from Response Elaboration Training (Kearns, 1985) and Sound Production Treatment (Wambaugh, Kalinyak-Fliszar, West, & Doyle, 1998). The purpose of this study was to determine whether CAAST was associated with positive changes in verbal language and speech production with speakers with aphasia and AOS. METHOD: Four participants with chronic aphasia and AOS received CAAST applied sequentially to sets of pictures in the context of multiple baseline designs. CAAST entailed elaboration of participant-initiated utterances, with sound production training applied as needed to the elaborated productions. The dependent variables were (a) production of correct information units (CIUs; Nicholas & Brookshire, 1993) in response to experimental picture stimuli, (b) percentage of consonants correct in sentence repetition, and (c) speech intelligibility. RESULTS AND CONCLUSIONS: CAAST was associated with increased CIU production in trained and untrained picture sets for all participants. Gains in sound production accuracy and speech intelligibility varied across participants; a modification of CAAST to provide additional speech production treatment may be desirable.

Sound production treatment: effects of blocked and random practice.

PURPOSE: This investigation was designed to further the development of a treatment for acquired apraxia of speech (AOS), Sound Production Treatment (SPT), by examining the effects of blocked and random practice. METHOD: A multiple-baseline design across participants and behaviors was used with 6 speakers with chronic AOS and aphasia. Accuracy of production of target sounds in treated and untreated words produced in probe sessions served as the primary dependent variable. Stimulus generalization was also measured to phrase production and sentence completion. Participants received SPT applied with blocked presentation of treatment words (SPT-blocked) and SPT applied with random presentation of treatment words (SPT-random). RESULTS: Increases in accuracy of articulation of target sounds in treated words were observed for all participants for both conditions of treatment. SPT-random appeared to be associated with better maintenance for 2 participants. Generalization to untreated words was positive for all participants for SPT-random and SPT-blocked. Stimulus generalization effects varied across participants and measurement conditions; patterns of generalization did not appear to be associated with treatment condition. CONCLUSIONS: There may be an advantage for SPT-random for some speakers with AOS. Findings from the nonspeech motor learning literature may not translate directly to the treatment of AOS.

Semantic feature analysis: incorporating typicality treatment and mediating strategy training to promote generalization.

PURPOSE: This investigation was designed to examine the generalization effects of semantic treatment for word retrieval deficits in people with aphasia. Semantic feature analysis (SFA; Boyle & Coelho, 1995), typicality treatment (Kiran & Thompson, 2003), and mediating strategy training were combined to maximize potential generalization effects. METHOD: Treatment, which included SFA and a semantic feature judgment task, was conducted with 9 participants with chronic aphasia in the context of multiple baseline designs across behaviors. Typical and atypical exemplars were trained across animate and inanimate categories. Treatment was sequentially modified to overtly train the use of SFA as a mediating strategy. RESULTS: Eight of the 9 participants demonstrated improvements in naming of trained stimuli. Positive generalization effects were limited overall; possible response generalization was evident for 5 participants. Instruction in the use of a mediating strategy resulted in improved naming of treated words for all participants; however, generalization to untreated words did not occur. CONCLUSION: Treatment using SFA resulted in improved naming of treated typical and atypical exemplars in both animate and inanimate categories for 8 of 9 participants. Training in a mediating strategy also resulted in improved retrieval of experimental words. Regardless of intervention approach, generalization to untreated items was limited.

Treatment for acquired apraxia of speech: examination of treatment intensity and practice schedule.

PURPOSE: The authors designed this investigation to extend the development of a treatment for acquired apraxia of speech (AOS)--sound production treatment (SPT)--by examining the effects of 2 treatment intensities and 2 schedules of practice. METHOD: The authors used a multiple baseline design across participants and behaviors with 4 speakers with chronic AOS and aphasia. Accuracy of production of trained and untrained words in phrases served as the dependent measure. Participants received 4 permutations of SPT (i.e., intensive-blocked, intensive-random, traditional-blocked, and traditional-random) applied sequentially to different lists of words. RESULTS: Positive changes in accuracy of articulation were observed for all participants for all phases of treatment. Two participants had a slightly poorer response to the traditional-random application of treatment. However, no clinically meaningful differences were noted among treatment applications when follow-up data were considered. CONCLUSIONS: Findings from this preliminary Phase II investigation suggest that similar outcomes may be achieved with SPT applied with different treatment intensities and different practice schedules. Extending treatment to achieve higher levels of accuracy may have improved maintenance effects, which may have revealed possible differences among conditions. In addition, overlap in methods used for random and blocked practice may have minimized distinctions between these conditions.

Apraxia of speech: perceptual analysis of trisyllabic word productions across repeated sampling occasions.

PURPOSE: Early apraxia of speech (AOS) research has characterized errors as being variable, resulting in a number of different error types being produced on repeated productions of the same stimuli. Conversely, recent research has uncovered greater consistency in errors, but there are limited data examining sound errors over time (more than one occasion). Furthermore, the influence of conditions of stimulus presentation (blocked vs. random) on sound errors remains uncertain. The purpose of this investigation was to examine the effects of repeated sampling and conditions of stimulus presentation on speech sound errors for 11 speakers with AOS/aphasia. METHOD: Trisyllabic words consisting of 7 target phonemes in the initial position served as stimuli. On 3 occasions, stimuli were elicited under 2 conditions: blocked (by phoneme) and randomized presentation. Speech productions were analyzed via narrow phonetic transcription. RESULTS: Findings revealed a similar overall mean percentage of errors in both conditions and across sampling occasions. Distortions were the dominant error type. CONCLUSION: There was no obvious pattern of responding across sampling occasions or conditions of stimulus presentation. The dominant error type differed among target phonemes, but there appeared to be some degree of consistency in the error types produced for the majority of target phonemes.