SH 565 Instrumentation in Communicative Disorders

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SH 565- Instrumentation in Communicative Disorders

• Spring 02

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Text/Lab Books

• Text Clinical Measurements of Speech Voice by
  RJ Baken
• Laboratory Assignments Will be handed first day
  of class and some addendums may be handed out in
  class in terms of instruction on software to be
  used.

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Instrumentation Concepts

• CSL- Acoustic parameters (Frequency, Shimmer,
  Jitter, Intensity, Formants, Harmonics, Open
  Quotient)
• Sound Pressure Level- Intensity
• Aerophone- Intensity, Frequency, Subglottal
  pressure, Airflow, Vital capacity
• Nasometer- Nasalance
• Speechviewer Therapy for phonology, voice

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Course Design

• Lectures
• Laboratory exercises
• Demonstrations

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Laboratory Assignments

• Handouts in class
• Some labs will involve
• Independent calculations
• Instrumentation to complete
• 70 of grade

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Quizzes

• Quizzes will be given the presentation week and
  the content of each quiz is indicated on your
  syllabus.
• 20 of total grade

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Presentation

• Topics are listed on syllabi with number of
  participants
• Some topics may be changed in advance of the day
  of the presentation
• All presentations have specific criteria in which
  to address on syllabi
• 20 of grade

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Why Instrumentation?

• Speech voice are not a product of physiological
  processes
• Problem in a speech system is a symptom, not a
  disorder (Speech subsystems effected)
• Therapy involves getting rid of symptoms
• Must change functionSo, must understand system
  functioning

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How To Assess Symptoms?

• Pinpoint abnormality by listening?
• Sometimes? Most problems lie under the surface.
• Ears not as reliable as you think!
• Perception differs from function
• Auditory system creates a whole picture and we
  need to assess the parts of speech.

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True Assessment
Structure
Somatic Function
Physiological Assessment
Physical Assessment
Speech Assessment
Aerodynamics
Acoustics
Perceptual Features
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Objectives

• How speech production measures are taken
  accurately.
• Understanding what your data means.
• Being able to calculate measures by hand so you
  understand what the computer is doing
• Than use the computer!!

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Calibration

• Instruments produce outputs
• Output numerical value that the transducer is
  sensing
• Calibration is the process for determining the
  equivalence between the output of a system and
  standard units of measurement
• Ex. 1cm on a chart is 0.5 cm H20

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Calibration

• All instruments must be calibrated
• Even commercial instruments have to report final
  values in conventional units- Need to be
  periodically tested

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Calibration

• Calibration begins with a known value (we measure
  its output in volts, etc,)
• Inject 500 ml into a spirometer and note the pen
  movement
• 500 ml of air causes the pen to move 4 cm
• If 4 cm of pen motion 500 ml what is the value
  for 1 cm of movement?
• 500 ml 1cm
• 4 cm ?

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Calibration

• (500/4) 1 125 ml
• So, 1cm 125 ml
• Lab exercises
• Several problems
• Calibration of Aerophone for flow Nasometer for
  nasalence

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Oscilloscope

• Makes electrical waveforms and voltages visible
  on screen
• It allows us to see speech waveforms Airflow,
  Pressure, EGG
• Can be computerized or separate module for
  calibration, etc.

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Reading Oscillograms

• Utilize oscillograms of the acoustic signal to
  visualize amplitude and time based data
• Mean vocal period
• Fundamental frequency
• Peak-to-Peak amplitude
• Segment speech into phones based on their
  acoustic features

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Reading Oscillograms
Comfortable Pitch /a/
t (sec) .0083 Fo (Hz) 120 Amp (volts) 25
6 cycles in 50 ms 50/6 8.33 ms or .0083 sec F0
(Hz) 1/t (sec) 1/.0083 120 Hz
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Reading Oscillograms
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Reading Oscillograms