Acoustic:
  Magnitude and timing of F2 movements
  F2 slope
Some dysarthric speakers have been shown to have a reduced vowel space in which formant values for non-neutral vowels shit to a more neutralized pattern (schwa).  This compression indicates that speakers with dysarthria have reduced ranges of F1 and F2 frequencies.
 An F1 that is higher or lower in frequency than normal means that the tongue is not achieving the appropriate height for the vowel; a higher or lower than normal F2 frequency indicates that the tongue is too far forward or too far back.
Therapy implication:  Slowing rate is often used as a procedure to help dysarthric people achieve appropriate placement for vowels.  Using technology can tell you if your therapy is working because the F1/F2 space will increase (showing that tongue movements become more precise in reaching vowel targets) if it is working which will subsequently result in improved intelligibility.
F2 transitions:  F2 is related to place of articulation because it is linked to tongue advancement.  The portion of the formant that contains a transition is measured in terms of its slope.  That is, the duration of the transition is measured in milliseconds, and the extent of the transition is measured in Hz, resulting in a slope index (Measure of a formant transition based on the duration and frequency extent of the transition. Measured in hertz per millisecond) measured in Hz/ms.  A flatter slope reflects an articulatory movement that is made over a greater period of time.  This indicates that tongue movement is slower with less range of movement.
The slope index provides diagnostic information regarding whether tongue movement is close to or far from normal and provides ongoing information regarding the course of the disease and its effect on speech.  Women without neurological problems have a slope of 3.76 to 5.4 Hz/ms (a steep slope, showing that F2 frequency changes rapidly within a short period of time as the tongue makes quick adjustments for the particular sound.  A slope of 3.0 Hz/ms seem to distinguish normal speakers and those with ALS, and a slope index of 2.5 Hz/ms distinguish dysarthric patients with good and poor intelligibility.  Reduced slopes indicate: weaker and slower tongue movements and reduced range of articulatory motion.
Formant trajectories that tend to cluster around 500 and 1500 hz for many of the words reflect vowel centralization.
Vocal loudness is used to treat the voice of those with Parkinson’s. With increased intensity, if the degree of the frequency change of the F2 transitions increase, especially for high front vowels.  This shows that articulation movement is increased.

Diadochokinetic rate:  average rate, intensity variations during repetitions
   Alternating motion rates (AMRs) using /p,t, k/
Normal AMRs are about 6.5 Hz (or can complete 6.5 /p/ per second) and relatively regular in duration and amplitude.
    Looking for blurring of articulation, pace or rate
    Of abnormalities
VOT-time between the release of a stop consonant and the start of phonation.  Longer VOT values are associated with English voiceless stops while shorter VOT values are associated with English voiced stops.
  Pitch and intensity magnitude during sustained vowels
  Pitch and intensity variability during sustained vowels
Pitch: FoSD for normal conversation is around 20-35 Hz; 3-6Hz for ah;  Pitch sigma for normal speakers  2-4 semitones
   Amplitude variability- SD= 10dB SLP
   Unevenness in loudness or pitch
  Measures of nasal resonance (Nasometer)
Maximum phonational frequency Range (3 octaves is normal for adults  = 80Hz-700Hz for males; 135Hz-1000 Hz for females; probably average or 30 semitones or 2.5 octaves (normal 22.7 semitones; abnormal 16.4 semitones)
Dynamic range= soft (not whispered) to loudest= 50dB to about 115dB; minimum dynamic range is 30dBSPL
:
 Note the time required to complete the sentence “You wish to know all about my grandfather.”  It should be less than 2 seconds with normal variability in syllable duratin and amplitude (energy tracing), and normal variability and declination in fo across the sentence (pitch tracing)
 Physiologic
  Respiration:
The four respiratory features important for speech production:
Pressure: forces generated by the respiratory process, which form the power for speech
Volume: amount of air in the lungs and airway
Flow: change in volume of air over time
Chest wall shape:  the positioning of the chest wall (ribcage, diaphragm, and abdominal muscles) for speech breathing.  Because they are related, knowing the parameter of one, we can make inferences about the others.  I.e., knowing measurements of chest wall shape, we can estimate lung volume changes.
   Breathing rate (16-18 cycles/minute norm)
   Regularity of breathing
Respiratory driving pressure (differences between high and low    pressure areas that causes air to flow between these areas)
Air pressure needed for speech
    (goal = 5 sec with straw depth of 5 cm)
 
   Vital Capacity (5-6000ccs norm)
Sub glottal air pressure is consistent with the about of pressure inside the mouth during the closed portion of a stop consonant /p/.  The sub glottal and oral pressure is equal in this instant.
 

Overview of Instrumentation used in Motor Speech—
Respiration:
Pneumotachograph: A devise to measure airflow.  ml/s of airflow over the duration of an utterance; peak flow rates during production of stops and fricatives.
 Low peak: smaller vocal tracts, greater resistances, lower elastic recoil
 High airflow: inefficient valving
Spirometer (VC, TV)- Instruments that measures lung volumes (wet/dry spirometers)
Plethysmograph or linearized magnetometers:  measure movements of the rib cage and abdomen.  Plethysmograph: bands around the chest and abdomen.  As the chest and abdominal walls expand and contract, the changes in their areas are measured.  The rib cage and abdomen can be assessed independently or combined to calculate lung volume.
Magnetometer:  Electromagnet fields are generated by two coils.  The changes in the strength of the current between the coils is determined by the distance between the coils.  The distance changes because of the movement of the chest wall.  Volume of the lungs, rig cage or abdomen is measured at the beginning and end of an utterance.   The volume expended- the initiation values minus the termination values.

Breathing patterns for speech
a. abdomen is smaller, rib cage larger than during relaxation to allow for quick inspirations, the rib cage is more efficient than the abdominal wall at moving air from the lungs because a greater portion of the surface of the lungs is adjacent to the rib cage.
b. Kinematic analysis (lung volumes are estimated from rib cage and abdominal movement)
a. Speech is produced in midrange of the VC; about twice the volume of quiet tidal breathing
b. Lung volumes, pressures, and flows are influenced by linguistic considerations such as clause boundaries and number of clauses
i. Inspirations are timed with naturally occurring breaks in the linguistic message
ii. Complex speaking tasks result in smaller number of syllables per breath group, slower speaking rate, and greater average volume of air expended per syllable
iii. When speaking loudly, when inhale: a greater volume of air in a shorter amount of time; very soft speech at lower volumes.
iv. Voiceless stops and fricatives need high flow, voiced stomps and fricatives need lower
v. Whispered speech terminate breath groups at lower lung volumes, use fewer syllables per breath group, expend more air per syllable, lower sub glottal pressure.