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Marshall, R. C., Gandour, J., & Windsor, J. (1988). Selective impairment of phonation: A case study. Brain and Language, 35 , 313-339. What to get from this case?. Methods of diagnosis Use of sound displays - time-pressure waves and spectrograms
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Marshall, R. C., Gandour, J., & Windsor, J. (1988). Selective impairment of phonation: A case study. Brain and Language, 35, 313-339.
What to get from this case? • Methods of diagnosis • Use of sound displays - time-pressure waves and spectrograms • Components of speech production -- phonation in particular • Separation (dissociation) of elements in production • Interaction of processes in normal speech • Consequently, difficulty in diagnosis & treatment
Visual displays of DT speech • Time waveform p. 327 • Fo trace (Fo plot) p.327 • Spectrograms (many e.g. Fig. 7, p.325) • Relative peak Intensity or stress (Fig.8) • VOT (voice onset time)
Terms and concepts to know • Dissociation • Decorrelation between symptoms or processes; used to support autonomous functions or modules • Apraxia • Motor disorder- an impairment of selecting, planning, executing movements in normal fashion. • CVA • Cerebral vascular accident • Crainiotomy • Skull surgery
Dysarthria • A speech disorder due to weak and poorly coordinated speech muscles. Speech may be slow and imprecise. It is basically symptom of many problems including cerebral palsy, various degenerative diseases, poisons, and strokes.
Summary- apparent Broca's aphasia with speech apraxia • Verb shifted right, stressed syllables only • Abnormal fundamental frequency (Fo) • DT could whisper and use electrolarynx without error
Causal factors in patient's apraxia • Lesion • Efforts to compensate • Interaction among components
Various diagnostic procedures used • Brain scan • Various language tests (p.317) including the BDAE • Assessment of specific speech deficits (below)
Phonation • Larynx - glottis, supraglottal, subglottal • Electrolarynx and its function • Whispering
Stroke • Infarct (tissue death due to restricted circulation) • TIA- transient ischemic attack:
Prosodics • Fundamental frequency, F0 pattern
Specific deficits • Phonation • Articulation --phonological analysis of errors p.321 • Syntax • Dissociation of phonology and articulation
Keys to diagnosis • Whispering, writing, and use of electrolarynx
H.E. 's TIA (transient ischemia attack) • Symptoms- depend on brain region with blockage • Evaluation - MRI, carotid arteries, heart, clinical exam • Cause -- generally uncertain • Treatment • Prognosis
Time-pressure wave showing disruptive effects on encoding thoughts
Schulz, G. M., Varga, M., Jeffires, K., Ludlow, C. L., & Braun, A. R. (2005). Functional neuroanatomy of human vocalization: An H215O PET study. Cerebral Cortex, 15(12), 1835-1849. • Thus, when voiced speech (oral articulatory movements plus vocalization) is contrasted with whispered speech (oral articulatory movements alone) the differences should selectively reflect the demands associated with vocalization. We hypothesized that these would include activation of the midline visceromotor circuit — the set of regions that comprise the species specific call system in lower mammals — as well as neocortical motor areas.
Schulz 2 • We also hypothesized that functional connections between these systems would be observed only the during voiced speech condition, suggesting a neural substrate for neocortical modulation of the midline circuit during human phonation.
Schulz 3 • our results suggest that human vocalization is not exclusively regulated by neocortical or visceromotor mechanisms, but by a combination of both.
Schulz 4 • The greater degree of voluntary control that humans have over phonation can be explained by neocortical regulation of these visceromotor structures. • (See Keith Hayes video bits- Vicki and voluntary vocalization?)
Vicki learns to talk! • Keith Hayes and his wife spent lots of time teaching Vicki.
Voluntary vocal control in chimps? • Chimps unlike some dogs and all children have little or no voluntary control over their vocal tracts.
Voluntary control in 17 month old Kate • She’s certainly vocalizing something!
Schulz 5 • Finally, there are areas in the temporal lobe and cerebellum that are coactivated and functionally coupled to both visceromotor and neocortical systems during voiced speech production. • These regions may support vocal self-monitoring, providing crucial information for regulation of the motor areas, i.e. complex on-line adjustments of pitch and airflow that depend upon perception of one's vocal output.