SH 565- Instrumentation in Communicative Disorders Spring ‘02

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.

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

Course Design Lectures Laboratory exercises Demonstrations

Laboratory Assignments Handouts in class Some labs will involve: –Independent calculations –Instrumentation to complete 70% of grade

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

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

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 function…So, must understand system functioning

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.

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

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!!

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

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

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 ?

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

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.

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

Reading Oscillograms Comfortable Pitch / a / t (sec)=.0083 F o (Hz)= 120 Amp (volts)= 25 6 cycles in 50 ms 50/6= 8.33 ms or.0083 sec F 0 (Hz)= 1/t (sec) 1/.0083= 120 Hz

Reading Oscillograms