title: Dissociating oral motor capabilities: Evidence from patients with movement disorders.
abstract: Abnormal articulation rate is a frequent symptom in neurogenic speech disorders. Performance rates in speech-like or nonspeech tasks involving the vocal motor apparatus are commonly accepted predictors of speech motor function in general and of articulation rate in particular. However, theoretical arguments and behavioral observations in populations with disordered speech indicate that different oral motor behaviors may be governed by distinct mechanisms. The objective of the present study was to expand our knowledge of the relationship between speech movements, on the one hand, and speech-like and nonspeech oral motor behaviors, on the other, by using a rate paradigm. 130 patients with neurological movement disorders of different origins and 130 neurologically healthy subjects participated in the study. Rate data was collected in a speech task (oral reading/repetition), in speech-like tasks (rapid syllable repetitions), and in nonspeech tasks (rapid single articulator movements of the tongue/lips). The main analyses involved a multiple single-case method, by which we tested for differences among each patient's performance rates on the three task types. The results disclosed statistically significant (classical and strong) dissociations between movement rates obtained from the speech task and those obtained from speech-like and nonspeech oral motor tasks in a number of patients. The findings can be interpreted as reflecting major differences in task demands and underlying control mechanisms. The validity of diagnostic indices for speech obtained from speech-like or nonspeech tasks must thus be called into question.
authors.affiliation: Clinical Neuropsychology Research Group, Institute of Phonetics and Speech Processing, Ludwig-Maximilians-University München, Schellingstr. 3, 80799 Munich, Germany. Electronic address: anja.staiger@ekn-muenchen.de.
authors.forename: Anja
authors.initials: A
authors.lastname: Staiger
authors.affiliation: Clinical Neuropsychology Research Group, Institute of Phonetics and Speech Processing, Ludwig-Maximilians-University München, Schellingstr. 3, 80799 Munich, Germany.
authors.forename: Theresa
authors.initials: T
authors.lastname: Schölderle
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Tübingen, Calwer Str. 14, 72076 Tübingen, Germany; Institute for Clinical Epidemiology and Applied Biometry, University of Tübingen, Silcherstr. 5, 72076 Tübingen, Germany.
authors.forename: Bettina
authors.initials: B
authors.lastname: Brendel
authors.affiliation: Clinical Neuropsychology Research Group, Institute of Phonetics and Speech Processing, Ludwig-Maximilians-University München, Schellingstr. 3, 80799 Munich, Germany.
authors.forename: Wolfram
authors.initials: W
authors.lastname: Ziegler
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D015331:Cohort Studies; D004401:Dysarthria / Q000175:diagnosis / Q000503:physiopathology; D005260:Female; D006801:Humans; D008046:Lip / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D009069:Movement Disorders / Q000175:diagnosis* / Q000503:physiopathology*; D011932:Reading; D015203:Reproducibility of Results; D012727:Sex Characteristics; D013060:Speech; D013068:Speech Production Measurement; D014059:Tongue / Q000503:physiopathology; D055815:Young Adult
keywords: Alternating motion rates; Articulation rate; Diadochokinesis; Dysarthria assessment; Oral motor control; Single case dissociations