Preparing an E-learning-based Speech Therapy (EST) efficacy study: Identifying suitable outcome measures to detect within-subject changes of speech intelligibility in dysarthric speakers

Abstract We explored the suitability of perceptual and acoustic outcome measures to prepare E-learning based Speech Therapy (EST) efficacy tests regarding speech intelligibility in dysarthric speakers. Eight speakers with stroke (n = 3), Parkinson’s disease (n = 4) and traumatic brain injury (n = 1) participated in a 4 weeks EST trial. A repeated measures design was employed. Perceptual measures were (a) scale ratings for “ease of intelligibility” and “pleasantness” in continuous speech and (b) orthographic transcription scores of semantically unpredictable sentences. Acoustic measures were (c) “intensity during closure” (ΔIDC) in the occlusion phase of voiceless plosives, (d) changes in the vowel space of /a/, /e/ and /o/ and (e) the F0 variability in semantically unpredictable sentences. The only consistent finding concerned an increased (instead of the expected decreased) ΔIDC after EST, possibly caused by increased speech intensity without articulatory adjustments. The importance of suitable perceptual and acoustic measures for efficacy research is discussed.

[1]  H. Scheffé.  An Analysis of Variance for Paired Comparisons , 1952 .

[2]  A. Aronson,et al.  Differential diagnostic patterns of dysarthria. , 1969, Journal of speech and hearing research.

[3]  L. Boves.  The Phonetic Basis of Perceptual Ratings of Running Speech , 1984 .

[4]  H. Ackermann,et al.  Articulatory deficits in parkinsonian dysarthria: an acoustic analysis. , 1991, Journal of neurology, neurosurgery, and psychiatry.

[5]  Dick R. van Bergem,et al.  Acoustic vowel reduction as a function of sentence accent, word stress, and word class , 1993, Speech Commun..

[6]  S. Rvachew.  Speech perception training can facilitate sound production learning. , 1994, Journal of speech and hearing research.

[7]  Martine Grice,et al.  The SUS test: A method for the assessment of text-to-speech synthesis intelligibility using Semantically Unpredictable Sentences , 1996, Speech Commun..

[8]  Raymond D. Kent,et al.  Quantification of motor speech abilities in stroke: Time-energy analyses of syllable and word repetition , 1999 .

[9]  G. Weismer,et al.  The effects of a flattened fundamental frequency on intelligibility at the sentence level. , 1999, Journal of speech, language, and hearing research : JSLHR.

[10]  Bronagh Blaney, John Wilson.  Acoustic variability in dysarthria and computer speech recognition , 2000 .

[11]  S. Countryman,et al.  Intensive voice treatment (LSVT®) for patients with Parkinson's disease: a 2 year follow up , 2001 .

[12]  Paul Boersma,et al.  Praat, a system for doing phonetics by computer , 2002 .

[13]  Marc S De Bodt,et al.  Intelligibility as a linear combination of dimensions in dysarthric speech. , 2002, Journal of communication disorders.

[14]  Raymond D. Kent,et al.  Toward an acoustic typology of motor speech disorders , 2003, Clinical linguistics & phonetics.

[15]  R. Teasell,et al.  Intensity of Aphasia Therapy, Impact on Recovery , 2003, Stroke.

[16]  M. Horstink,et al.  Improvement of voicing in patients with Parkinson’s disease by speech therapy , 2003, Neurology.

[17]  Kate Bunton,et al.  Perceptual effects of a flattened fundamental frequency at the sentence level under different listening conditions. , 2003, Journal of communication disorders.

[18]  Jack M Winters,et al.  A telehomecare model for optimizing rehabilitation outcomes. , 2004, Telemedicine journal and e-health : the official journal of the American Telemedicine Association.

[19]  R. R. Robey.  A five-phase model for clinical-outcome research. , 2004, Journal of communication disorders.

[20]  Stuart Cunningham,et al.  The Effect of Three Practice Conditions on the Consistency of Chronic Dysarthric Speech , 2004 .

[21]  A. Basso.  How intensive/prolonged should an intensive/prolonged treatment be? , 2005 .

[22]  Raymond D. Kent,et al.  Dysarthria associated with traumatic brain injury: speaking rate and emphatic stress. , 2005, Journal of communication disorders.

[23]  P. Boersma.  Praat : doing phonetics by computer (version 4.4.24) , 2006 .

[24]  H. Abdi.  The Bonferonni and Šidák Corrections for Multiple Comparisons , 2006 .

[25]  G. Kwakkel.  Impact of intensity of practice after stroke: issues for consideration. , 2012, Disability and rehabilitation.

[26]  R. Palmer,et al.  Methods of speech therapy treatment for stable dysarthria: A review , 2007 .

[27]  R. Schmidt,et al.  Principles of motor learning in treatment of motor speech disorders. , 2008, American journal of speech-language pathology.

[28]  Assessment of Acquired Neurogenic Communication Disorders in Adults using a Telerehabilitation Application , 2008 .

[29]  J. Jankovic.  Parkinson’s disease: clinical features and diagnosis , 2008, Journal of Neurology, Neurosurgery, and Psychiatry.

[30]  P. Boersma.  Praat : doing phonetics by computer (version 5.1.05) , 2009 .

[31]  Joost van Doremalen,et al.  Optimizing non-native speech recognition for CALL applications , 2009, INTERSPEECH.

[32]  A. Geurts,et al.  Evaluating the feasibility and the potential efficacy of e-learning-based speech therapy (EST) as a web application for speech training in dysarthric patients with Parkinson's disease: a case study. , 2010, Telemedicine journal and e-health : the official journal of the American Telemedicine Association.

[33]  Henk van den Heuvel,et al.  E-learning-based speech therapy: a web application for speech training. , 2010, Telemedicine journal and e-health : the official journal of the American Telemedicine Association.

[34]  L. Beijer,et al.  Auditory discrimination as a condition for E-learning based Speech Therapy: a proposal for an auditory discrimination test (ADT) for adult dysarthric speakers. , 2011, Journal of communication disorders.

[35]  Raymond D. Kent,et al.  An acoustic study of the relationships among neurologic disease, dysarthria type, and severity of dysarthria. , 2011, Journal of speech, language, and hearing research : JSLHR.

[36]  L. Beijer,et al.  Evaluating the suitability of orthographic transcription and intelligibility rating of semantically unpredictable sentences (SUS) for speech traning efficacy research in dysarthric speakers with Parkinson’s disease , 2012 .

[37]  M. Grossman,et al.  Tone discrimination as a window into acoustic perceptual deficits in Parkinson's disease. , 2012, American journal of speech-language pathology.

[38]  K. Atler.  An Argument for a Dynamic Interrelated View of Occupational Experience , 2015 .