18 - Disordered Acoustics Review

Question 1

What are the 5 voice measures that we use to quantify dysarthric speech?

Answer 1

• jitter
• shimmer
• harmonic-to-noise ratio
• voice breaks (spasms)
• tremor of F0 and intensity

Question 2

Name 2 of the 5 ways that dysarthric speech might affect vowel formants

Answer 2

• F1 range: restrictions in elevation and/or lowering
• F2 range: restrictions in retraction and/or advancement
• Centralized F1 and F2: formants converge toward a central schwa
• F1 and F2 variability: variable formants especially during prolonged vowels
  
  • irregular (i.e. chorea/dystonia) or regular (i.e. tremor) variation
• diphthong formants restricted and/or slow: reduced F2 slope

Question 3

Name 2 of the 5 ways that dysarthric speech might affect stops

Answer 3

• spirantization: prolonged fricative-like noise replaces transient burst
• voicing throughout closure: continuous voicing replaces stop gap
• nasalized stops (i.e b becomes m)
• voice onset time variability
• maximum plosive repetition rate reduced and/or variable

Question 4

Name the 3 ways that dysarthric speech might affect fricative noise

Answer 4

• fricative noise is weak or absent
• peak and average frequency of ‘s’ and/or ‘sh’ is abnormal
• difference between average frequency of ‘s’ and ‘sh’ is restricted

Question 5

Name 2 of the 6 ways that dysarthric speech might affect prosodic measures (intonation, tone, stress, rhythm, etc)

Answer 5

• abnormal utterance durations (fast or slow rate of speech; words per minute)
• reduced average utterance intensity (quiet/hypophonic speech)
• reduced speech/noise (S/N) ratio
• reduced intensity variability across sentences (monoloudness)
• reduced fundamental frequency variability across sentences (monopitch)
• reduced declination of F0 across sentences (monopitch)

Question 6

To identify the source of a tremor, we can do isolation tasks, like blocking the jaw open to see if it goes away. How would a tremor originating from the ABDOMEN affect F1, F0, and intensity?

Answer 6

F1 - steady
F0 - steady
Intensity - variable

Question 7

To identify the source of a tremor, we can do isolation tasks, like blocking the jaw open to see if it goes away. How would a tremor originating from the JAW affect F1, F0, and intensity?

Answer 7

F1 - variable
F0 - steady
Intensity - variable

Question 8

To identify the source of a tremor, we can do isolation tasks, like blocking the jaw open to see if it goes away. How would a tremor originating from the LARYNX affect F1, F0, and intensity?

Answer 8

F1 - steady
F0 - variable
Intensity - variable