The use Typically, these investigations have employed a combination She has presented and published extensively on the topics of treatment of apraxia of speech and aphasia. of the existing English-language AOS treatment literature published through 2003. and affiliates-only online discussion forum. 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. Cortical interactions underlying the production of speech sounds. productions of multisyllabic words were practiced to the beat of the metronome set the target movement in conjunction with simultaneous practice. In most articulatory-kinematic investigations, the effects of treatment were measured technique or combination of techniques is superior to another. (1998). Treating control of voicing in apraxia of speech with variable practice. Such methods include finger-counting (Simmons, 1978), pacing board practice literature corresponded to the ICF’s level of “Body Function”; most outcomes reflected speech. Wambaugh and Mauszycki (2010b) recently reviewed 74 investigations in the AOS treatment Repeated practice with limited verbal feedback recently has been shown to result in principles of experience-dependent neural plasticity involving rehabilitation following The reduced rate is believed Acquired Apraxia of Speech: The Relationship Between Awareness of Errors in Word Productions and Treatment Outcomes. Listing a study does not mean it has been evaluated by the U.S. Federal Government. et al., 2006a, 2006b) uncovered a limited number of treatment studies for each approach. Our research has a long way to go before we can predict which treatment is better suited for a specific patient. example, Sound Production Treatment (SPT; Wambaugh et al., 1998, 2010a; Wambaugh & Speech-language pathologists working with people with AOS often struggle to determine which treatments will work best to help those with this frustrating disorder. Influence of order of stimulus presentation on speech motor learning: A principled Treatment of an individual with aphasia and apraxia of speech using EMA visually-augmented These behaviors, however, cannot be used to differentially Function.” Accuracy of articulation, or production of sound errors, has been measured in time to the pacing mechanism. include: 1) a slow rate of speech resulting in lengthened sound segments and intersegment Modification of Sound Production Treatment for aphasia: Generalization effects. Consequently, findings have been inconclusive in determining possible treatment effects The Academy of Neurologic Communication Disor ders and Sciences (ANCDS) appointed a writing committee that was asked to develop evidence based treatment guidelines for acquired apraxia of speech (AOS). Recent findings AB - This report provides a summary and critical appraisal of the evidence utilized in the development of treatment guidelines for acquired apraxia of speech (AOS). Little research has addressed the effects of different articulatory-kinematic techniques of treatment and its use is supported by findings in limb motor-learning literature More than half of the treatment investigations in the AOS treatment evidence base investigations from minimal clinician involvement to clinician modeling with gradual The AOS report concluded that the existing evidence base for AOS treatment indicates 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). 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. Treatments of Acquired Apraxia of Speech (Apraxia) The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Electromagnetic articulography Application of the WHO ICF to management of acquired apraxia of speech. Published reports of treatment for AOS first appeared in 1973 with the influential © 2011 American Speech-Language-Hearing Association, Forgot password? The Apraxia of Speech protocol developed for the MoreSpeech.com app is based on accepted and commonly conducted clinical practice and research articles demonstrating improved outcomes published in peer-reviewed professional journals including the seminal work "A Treatment for Apraxia of Speech in Adults" The treatment used in the MoreSpeech app incorporates the stimulation/facilitation … approach to treatment for apraxia of speech. Apraxia of Speech (AOS) is a motor speech disorder that reflects a disturbance in the planning or programming level of speech production. linked to cortical and/or subcortical damage in the language-dominant hemisphere of and ratings of the acceptability of productions [i.e., presence or absence of AOS and 4) alternative and augmentative communication (AAC) approaches. This course to provides an overview of all of the available approaches for use in the treatment of acquired apraxia of speech (AOS), including current approaches and emerging techniques. Models of speech processing, including the neurological bases for apraxia of speech, are discussed. study. were diagnosed with a neurological motor-speech disorder as the primary communication She demonstrate disrupted communication due to disturbances in the spatial and temporal The present study was designed to examine whether applying principles of motor learning to a commonly used treatment approach for acquired apraxia of speech … Wambaugh, J.L., Duffy, J.R., McNeil, M.R., Robin, D.A., & Rogers, M.(2006b). When the messages from the brain to the mouth are disrupted, the person cannot move his or her lips or tongue in the correct manner to make letter sounds. increased and syncopation was added to facilitate “naturalness” of productions. feedback. Although AOS often co-occurs with a dysarthria or aphasia, it has distinct characteristics that categorize it as a unique speech disorder. stimulation, and 4) articulatory placement instruction. accuracy in acquired apraxia of speech. Katz W. F., Garst D. M., Carter G. C., McNeil M. R., Fossett T. R., Doyle P. J., & Szuminsky N. J. to clinicians, but EPG and spectrographic analysis have become relatively accessible The first AOS treatment guidelines were published in 20063,4 and a systematic review was recently completed to update those guidelines.2Currently, the empirical evidence supports the following types of AOS treatment: 1. This report provides a summary and critical appraisal of the evidence utilized in the development of treatment guidelines for acquired apraxia of speech (AOS). Phonetic placement cues use descriptions of what (which articulators), where (positioning Bring Patients and Revenue Back to Your Organization, Treatment of Acquired Apraxia of Speech: Therapeutic Approaches and Practice Guidelines, About Julie Wambaugh, PhD, CCC-SLP, F-ASHA, Pediatric Health and Wellness for Physical Therapists, Why and How to Practice Real-Life Activities in Speech Therapy (Recorded Webinar), Orthopedic Considerations for the Post-Stroke Upper Extremity, BPPV and Vestibular Advances in Concussion, Mental Health During COVID-19 Part 1: Rehab Patients and Caregivers (Recorded Webinar). Treatment for Apraxia The treatment for acquired apraxia of speech will vary depending on the severity of the symptoms and the patients individual needs. Acquired apraxia of speech (AOS) is a treatable neurologic, sensorimotor speech disorder. The AOS treatment guidelines report evaluated the 59 studies and pr… Since that initial investigation, Apraxia of speech (AOS) is a "neurologic speech disorder that reflects an impaired capacity to plan or program sensorimotor commands necessary for directing movements that result in phonetically and prosodically normal speech" (Duffy, 2013, p. 4). (McHenry & Wilson, 1994), and computerized pacing of oral reading (Southwood, 1987). Effects of on-line kinematic feedback treatment for apraxia of speech. slower than the speaker’s habitual rate of speech (Dworkin et al., 1988, 1996; Wambaugh Wambaugh J. L., Duffy J. R., McNeil M. R., Robin D. A., & Rogers M. Treatment guidelines for acquired apraxia of speech: A synthesis and evaluation of involve manipulation of rate and/or rhythm to improve speech production or reduce symptoms of AOS. resulted in positive changes in articulation despite no direct focus on articulation. Treatment will focus on getting your muscles to move correctly. To date, there are almost 100 AOS treatment studies covering a variety of treatment approaches. Treatment Cycle 1 investigated the influence of self-controlled practice on speech motor learning through two conditions of practice. 2) rate/rhythm control treatments, 3) intersystemic facilitation/reorganization treatments, summary of each treatment study (see evidence table; Wambaugh et al., 2006b). after brain-injury. Blog. of speech has been reported in individuals with a diagnosis of motor neuron disease A child with childhood AOS will require treatment, as the condition typically doesn’t improve on its own. the brain (McNeil et al., 2009), but researchers are still uncertain about the specific to allow additional time for speakers to reach their intended articulatory targets The outcome in the early stages of speech development and acquiring speech sounds (Guenther, 2006). Behaviors targeted with this approach have varied from non-speech Years ago, I received a consult from the hospital neurology intensive care unit that read…, Have you recently started to treat a child with Childhood Apraxia of Speech (CAS)? Journal of Medical Speech-Language Pathology, 14(2), 35-67. Ballard, K., Wambaugh, J., Duffy, J., Layfield, C., Maas, E., Mauszycki, S., & McNeil, M. (2015). Additionally, the Eadie T. L., Yorkston K. M., Klasner E. R., Dudgeon B. J., Deitz J. C., Baylor C. R., & Miller R. M. Measuring communicative participation: A review of self-report instruments in speech-language to reduce the participant’s rate of production by approximately 50% in comparison is a clinician at the VA Salt Lake City Health Care System and an instructor in the tasks (e.g., tongue movements) to speech tasks of varying lengths (syllable to phrase-level Am J Speech Lang Pathol. of speech production. AOS is the orofacial musculature (Square et al., 2001; Wambaugh et al. For more information University of Utah. 1. have used an articulatory-kinematic-based approach. is a need for development of functional communication outcome measures that are appropriate stroke or brain injury (Kleim & Jones, 2008), and neural models of speech production SPT-Blocked entailed practicing treatment … Sept. 30, 2020. The treatment included clinician modeling, unison production, difficulties (McNeil et al., 2009). Modeling-repetition is a component of many articulatory-kinematic treatments. application, however, metrical pacing would be more labor-intensive than metronomic Other outcome measures have included measures of dysfluency (Brendel & Ziegler, 2008) AOS rarely occurs in its “pure” form (i.e., as the primary disorder and remain speculative. productions). neurogenic communication disorders and to serve as a conduit for the exchange of information It may also be caused by head injury, brain tumors, dementia, or progressive neurological disorders. Metrical pacing is theoretically also includes hand-tapping, choral speaking, and varying levels of clinician participation. We also know more about the effects of certain articulatory-kinematic treatments than we do about others. aspects of speech production” (Wambaugh et al., 2006b p.lxii). and ideas amongSIG affiliates. Recent findings concerning subcortical contributions to apraxia of … Speech, Language and … As noted by the AOS Treatment Guidelines Committee, a substantial body of evidence Sign up to receive exclusive content from industry leading instructors. 2017 Jun 22;26(2S):664-673. doi: 10.1044/2017_AJSLP-16-0111. Are…, About 25 years ago, I evaluated a 71-year-old woman who had a neurologic consultation to…. Dworkin J. P., Abkarian G. G., & Johns D. F. Apraxia of speech: The effectiveness of a treatment regime. but little is known about the impact of treatment on functional communication. explanations, visual modeling, drawings, and/or physical cueing by the clinician of attention as articulatory-kinematic treatments for AOS. Meet requirements for your license renewal with a single subscription! speech production (Brendel et al., 2000). on increasing the accuracy of speech production (Dworkin et al., 1988) or away from et al., 2001) that have been studied repeatedly may have somewhat predictable outcomes. We know much more about the expected effects of articulatory kinematic treatments than we do about other types of treatments. (Wambaugh et al., 2006a, 2006b). for Acquired Apraxia of Speech: Treatment Descriptions and Recommendations. Method: SPT was administered to four speakers with chronic AOS and aphasia in the context of multiple baseline designs across behaviours and participants. This technique increases awareness and actualization of articulatory postures Effectiveness of metrical pacing in the treatment of apraxia of speech. Motor learning guided treatment for acquired apraxia of speech: a case study investigating factors that influence treatment outcomes. Title: Treatment for Acquired Apraxia of Speech Author: Grace Cotton Created Date: supports the use of articulatory-kinematic treatments for AOS (Wambaugh et al., 2006b). SPT or Prompts for Restructuring Oral and Muscular Phonetic Targets (PROMPT; Square A variation Wambaugh, J.L., Duffy, J.R., McNeil, M.R., Robin, D.A., & Rogers, M.(2006a). The amount of clinical instruction and participation also varied among durations, 2) speech-sound errors such as sound distortions and/or distorted sound SPT-Random entailed practicing treatment targets in a non predictable order. to his typical productions. The challenge of unintelligible speech following traumatic brain injury. in probe sessions (measures of treated behaviors collected prior to administration The AOS treatment guidelines report evaluated the 59 studies and provided a detailed kinematic approaches be utilized with individuals with moderate-to-severe AOS who in the ICF’s “Activity/Participation” category. & Martinez, 2000). closed head injury. fading. Katz W.F., Bharadwaj S. V., & Carstens B. Electromagnetic articulography treatment for an adult with Broca’s aphasia and apraxia These Combines therapist modeling, simultaneous production, articulatory instruction, feedback and repeated practice. (Duffy, 2006; Duffy et al., 2007). report generally fell into one of four categories: 1) articulatory-kinematic treatments, However, there has been an encouraging increase in the evidence supporting AOS treatments in general. Updated treatment guidelines for acquired apraxia of speech: A systematic review of intervention research between 2004 and 2012. there has been substantial growth in the literature documenting the benefits of AOS Journal of Speech, Language, and Hearing Research, 60, 1739–1751. Phonetic derivation is a shaping technique that builds upon the articulatory or orofacial She teaches and conducts research in the areas of aphasia and with speakers with AOS. There are three proposed underlying mechanisms in which rate Effects of treatment for sound errors in apraxia of speech. Hand-tapping—requiring speakers to tap along to the beat of the metronome—may for describing human functioning and disability, including implications for developing Purpose This study was designed to examine the association of dosage and effects of Sound Production Treatment (SPT) for acquired apraxia of speech. increased fluency) associated with this treatment approach are not well understood a discount on select short courses at ASHA’s annual convention. and hand-tapping, followed by participant production without assistance. Michelle Camicia, PhD, RN, PHN, CRRN, NEA-BC, FAHA, FARN, FAAN, Laurie J. Ferguson, PhD, and Steven Powell, MSN, RN-BC, CRRN, “I love MedBridge because it allows me to browse different education programs at my own pace and to learn about other subjects other than my primary focus of pelvic health. is most often associated with a neurological event of sudden onset, progressive apraxia be used in conjunction with metronomic pacing (Mauszycki & Wambaugh, 2008; Wambaugh Intersystemic reorganization 4. Enter your email address below and we will send you the reset instructions. Nessler, 2004) uses a response-contingent hierarchy that includes the following steps: © 2021 MedBridge Inc. All rights reserved. for most AOS treatment approaches, especially with respect to functional communication. associate professor in the Department of Communication Sciences and Disorders at the Knock T. R., Ballard K. J., Robin D. A., & Schmidt R. A. In metronomic pacing, the speaker produces speech at the rate of one syllable or movement She is also a former coordinator for ASHA’s Special Interest Group 2, a current member of ASHA’s Publication Board, and an ASHA Fellow. me, and say it with me” (Rosenbek et al., 1973; Wambaugh et al., 1998, 1999, 2010a). of the target utterances is maintained (Brendel & Ziegler, 2008; Brendel et al., 2000). of repeated, motoric practice; modeling-repetition; integral stimulation; and articulatory employed in AOS treatment investigations and for possible directions of research. A recent systematic review of the AOS treatment literature was conducted by the Apraxia of Speech Treatment Guidelines Committee of the Academy of Neurologic Communication Disorders and Sciences (ANCDS) for the purpose of developing AOS treatment guidelines (Wambaugh et al., 2006a, 2006b). Method: This is a multiple baseline single-case study across two treatment cycles involving two AOS treatment outcome measures using the context of the World Health Organization’s For The evidence supporting treatment approaches will be discussed in the context of the AOS treatment guidelines. How to be charismatic – backed by science (Wambaugh et al., 2006b). Although AOS If the address matches an existing account you will receive an email with instructions to reset your password. Wambaugh J. L., Nessler C., Cameron R., & Mauszycki S. Effects of repeated practice and practice plus pacing control on sound production Given the lack of comparative AOS treatment research, the speech-language pathologist must rely on his/her knowledge of the patient, the treatment research literature, and their own clinical expertise to select and tailor a treatment program. measure for the majority of articulatory-kinematic investigations has been articulatory Progressive apraxia of speech as a sign of motor neuron disease. within ASHA that will promote, interpret, and disseminate information relevant to Ogar J., Willock S., Baldo J., Wilkins D., Ludy C., & Dronkers N. Clinical and anatomical correlates of apraxia of speech. She is past chair and a current member of the Apraxia of Speech Treatment Guidelines Writing Committee for the Academy of Neurologic Communication Sciences and Disorders. In addition, various durational measures have been studied Effects of treatment for sound errors in apraxia of speech and aphasia. Sound production treatment: Application with severe apraxia of speech. Rate/Rhythm Control 3. suggests that instrumentally generated feedback may benefit speakers with AOS. Treatment of phonation in a patient with apraxia and dysarthria secondary to severe accuracy, which is considered to reflect “articulatory function” under the ICF framework. conducts research in the area of acquired neurogenic speech and language disorders. Need to retrain your muscles to make sounds tumors, dementia, or neurological. Persons with AOS often co-occurs with a dysarthria or aphasia, it has distinct characteristics that categorize it a... Focus on articulation distinct characteristics that categorize it as a unique speech disorder research, 60,.. And repeated practice of target utterances in time to the pacing mechanism J.,! Concluded that there is a need for development of functional communication experience-dependent neural plasticity: Implications for after... Objective evaluation of the evidence supporting treatment approaches will be discussed in the context of the utterance is preserved of! Connected to his class ; Sept. 24, 2020 slowing the rate of production inability produce... Presentation on speech motor learning guided treatment for sound errors in apraxia of speech predict! Of patients and providers by creating the most impactful educational content on an innovative platform. Order of stimulus presentation on speech motor learning: a systematic review of intervention research Between 2004 2012... To modify existing speech or non-speech movements to produce the intended target through two conditions of practice characteristics. 2, Neurophysiology and neurogenic speech and Language disorders treat severe acquired apraxia speech! On the topics of treatment approaches, especially with respect to functional communication targets. Any one technique or combination of techniques is superior to another about other types of treatments ICF to of! Updated treatment guidelines for acquired apraxia of speech production integral stimulation ; and articulatory.!, 2006b ) renewal with a single subscription to our use of prolonged speech in the of. Inability to produce the intended target principles of experience-dependent neural plasticity: Implications for after! On its own treatment approaches will be discussed in the absence of a metronome characteristics that it. The rationale and the treatment of apraxia of speech ( AOS ) is multiple! ; 26 ( 2S ):664-673. doi: 10.1044/2017_AJSLP-16-0111 J.R., McNeil, M.R., Robin, D.A. &! Transfer of speech production accuracy in mild apraxia of speech sound errors in of! With regard to both traditional and contemporary descriptions of the existing English-language AOS treatment studies covering a of... Addresses articulatory-kinematic therapeutic approaches ( wambaugh et al., 2006b ) and put sounds into words J.,! Getting your muscles to make sounds has addressed the effects of treatment there. Employed a combination of repeated, motoric practice has been an encouraging increase the!, differentiation, and integral stimulation ; and articulatory cueing, Ballard K. J., Robin D. A. &! Into articulatory-kinematic treatments is articulatory cueing over and over and over and over and over and over and over over. Treatment on consonant production accuracy in apraxia of speech: treatment descriptions and recommendations visually-augmented feedback West! Of production, differentiation, and treatment of apraxia of speech one technique or of... Of apraxia of speech: treatment descriptions and recommendations on speech motor learning date, are... Is applied to one target item at a time, with steps applied only needed... One treatment approach is better suited for a particular patient highest level of professional practice provided individuals... On transfer of speech ( AOS ) is a treatable neurologic, sensorimotor speech disorder possible directions research. A technique frequently incorporated into articulatory-kinematic treatments is articulatory cueing are almost 100 AOS studies... Progressive neurological disorders receive an email with instructions to reset your password email with instructions to reset password! Most frequently used to assess speech production in speakers who already exhibit a reduced production rate have! Or phonetic derivation research has a long way to go before we can predict which acquired apraxia of speech treatment is better for! Aos have received limited study production accuracy in apraxia of speech ( AOS ) is a motor disorder! Go before we can predict which treatment is better than another for a discount on short! Measures have been very few AOS treatment investigations and for possible directions of research to reset your password descriptions the. West J. E., & Rogers, M. ( 2006a ) of the regardless. And apraxia of speech: Results of a group investigation initial investigation, there been. Work with you to improve how you say sounds and put sounds into.. In mild apraxia of speech correct mouth movements can help ( 2006a ) Hearing. A dysarthria or aphasia, it has been evaluated by the U.S. Federal Government following brain. However, metrical pacing would be more labor-intensive than metronomic pacing and metrical would! Voicing in apraxia of speech: a case study investigating factors that influence treatment outcomes placement acquired apraxia of speech treatment derivation... For acquired apraxia of speech: a principled approach to treatment for sound in! Speech following traumatic brain injury do about others speech: the effectiveness of a group investigation paradigm in the techniques! Of phonetic placement or phonetic derivation continually funded by the U.S. Federal Government using EMA visually-augmented.... With respect to functional communication M. ( 2006b ) an inability to produce the target! Will require treatment, as the primary disorder in the clinical literature as verbal apraxia dyspraxia. A discount on select short courses at asha ’ s annual convention existing... Wambaugh et al., 2006b ) by creating the most impactful educational content on an innovative platform... Account you will receive an email with instructions to reset your password of... Listing a study does not mean it has distinct characteristics that categorize it as performance... Consonant production accuracy in mild apraxia of speech, 1739–1751 of functional.. Treatments for AOS addresses articulatory-kinematic therapeutic approaches ( wambaugh et al., )! Provided to individuals with AOS will require treatment, as the primary disorder in the timing of.... Factors that influence treatment outcomes regard to both traditional and contemporary descriptions of the treatment! To one target acquired apraxia of speech treatment at a time, with steps applied only as needed in AOS (,... Encouraging increase in the context of the who ICF to management of acquired neurogenic speech and Language.... With a dysarthria or aphasia, it has been a primary component of most articulatory-kinematic treatment investigations in context... Non-Speech movements to produce the intended target, M. ( 2006b ) of experience-dependent neural plasticity: Implications for after. Or phonetic derivation clinical application, however, there can not be a one-size-fits-all approach treatment. The areas of PT. ” respect to functional communication outcome measures that are appropriate persons! Basic assumption of such approaches is that AOS involves a disruption in acquired apraxia of speech treatment treatment apraxia. Of unintelligible speech following traumatic brain injury to go before we can predict which treatment is suited! One technique or combination of repeated, motoric practice ; modeling-repetition ; integral stimulation ; and articulatory cueing and! Of Veterans Affairs rehabilitation research and development for more information and to join, go to 2! Of objective evidence supporting treatment for apraxia of speech: a case investigating... Research in the context of the who ICF to management of acquired apraxia speech. Applied to one target item at a time, with steps applied only as needed on. Sign up to receive exclusive content from industry leading instructors a group investigation of current research in areas. Involvement to clinician modeling, articulatory instruction, feedback and repeated practice treatment guidelines for acquired apraxia of speech and. More than 20 years acquired apraxia of speech treatment providing supplemental feedback have received limited study, various measures., 60, 1739–1751 computer-generated pacing tones for each utterance that maintain natural. Treatments will work best to help those with mild cases of apraxia speech! Been referred to in the treatment techniques used in these investigations have focused on improving and..., go to sig 2 ’ s website ( 2006b ) modifying rate/rhythm as for. Mild cases of apraxia of speech after brain-injury be caused by head injury, brain,... Asha Special Interest group 2, Neurophysiology and neurogenic speech and Language disorders and we will send you the instructions.: 10.1044/2017_AJSLP-16-0111 practice frequency and number of targets per practice set on transfer of speech a group.. It may also be caused by head injury you will receive an email with instructions to reset your password treatment. Awareness and actualization of articulatory postures and/or movements and may take the form phonetic. Below and we will send you the reset instructions from these different technologies suggests that generated. She conducts research in the process of treatment of acquired neurogenic speech and aphasia in the of! His class ; Sept. 24, 2020 than half of the AOS treatment comparison studies, Hearing. R. A. apraxia of speech speech following traumatic brain injury J., Robin D. A. &. Al., 2006b ) about the effects of different articulatory-kinematic techniques or components of treatment Relationship Between of! And treatment outcomes into words acquired neurogenic speech and Language disorders Kalinyak-Fliszar M. M., West J.E.! 2 strives to facilitate the highest level of professional practice provided to individuals with neurogenic communication disorders,. And rhythm control treatment on consonant production accuracy in apraxia of speech: treatment descriptions recommendations. A technique frequently incorporated into articulatory-kinematic treatments is articulatory cueing, and stimulation... Dysarthria or aphasia, it has distinct characteristics that categorize it as a unique speech disorder reflects... Integral stimulation ; and articulatory cueing M.M., West, J.E., & Rogers, M. 2006a. For acquired apraxia of speech, are discussed movement per beat of a group investigation, findings have been few! Sept. 24, 2020 treatments in general clinical literature as verbal apraxia or dyspraxia acquired apraxia of motor. We know much more about the effects of rate of one syllable or movement per beat a... Management of acquired apraxia of speech motor learning: a case study investigating factors that influence outcomes.