Lecture 24 Flashcards
What are the 4 different measures (non-imaging) that can be used to measure supralaryngeal structure and activities?
1) electromyography
2) Velotrace
3) Electropalatopgraphy
4) Electromagnetic Articulometer
What are the 3 imaging techniques?
1) ultrasound
2) magnetic resonance imaging
3) acoustic analysis
Electromyography is used to study ______ __________
Muscle contraction
Electromyography is used to study the underlying __________ of _________, __________, and __________
Movements; respiration, phonation, and articulation
Electromyography tells information about ________ activity by recording muscle ______ _______
Muscular; action potentials
What is the electrical activity that accompanies each muscle contraction called?
(Muscle) Action potentials
What are the two types of electromyography electrodes?
1) surface
2) inserted
Surface electrodes are not as ________ _______
Muscle specific
Hooked-wire electrodes are inserted ________ into the _______, and then the ______ is ________
Directly; muscle; needle; withdrawn
What are the two disadvantages of electromyography?
1) difficult to be certain that signal comes from muscle of interest
2) procedure is slightly uncomfortable for subject
Why can it be difficult to be certain what muscle the signal comes from during electromyography?
If the muscle is not singular, and is instead interconnected its hard to discern the signals source
What are the 3 major parts of a velotrace?
1) internal lever
2) external lever
3) push rod that connects the levers
How does the velotrace work?
It’s inserted through the nostril and the internal lever rests on the surface of the nasal passages and “traces” the velum. When the internal lever moves the external lever moves and the vertical movement of the velum can be tracked.
How does an electropalatography work?
A pseudopalate/ palatal prosthesis with electrodes is placed on the roof of mouth and when the tongue contacts them they are stimulated.
What are the 2 advantages of electropalatography?
1) can show coarticulation
2) provides visual feedback
What are 4 the disadvantages of electropalatography?
1) there are no electrodes (and therefore info) at the anterior of the alveolar, on the teeth, or on the velum
2) it is expensive to make the custom palate prosthesis for each subject
3) trouble with exact relaxation from one use to the next
4) if there is no contact there is no info
The electromagnetic articulometer (EMA) is a version of the _____________
Magnetometer
The EMA provides ___________ data
Articulatory
What are the 2 advantages of the EMA?
1) rapid tracking time
2) ability to track multiple articulators simultaneously
What is the disadvantage of the EMA?
Only points are measured so the behavior of the entire articulator is largely inferred
How does an ultrasound produce images?
By using reflective properties of sound waves
What are 4 advantages of ultrasound imaging?
1) non-invasive
2) small and portable
3) real-time data
4) no known biological hazards
What are the 2 disadvantages of ultrasound imaging?
1) tongue tip might not get imaged because the way the wave is reflected
2) creates a shadow when it hits bone
How does an MRI work?
Uses a magnetic field and radio waves to image a section of tissue
An MRI scanner consists of _______________ that _______ the body and create a _________ _____
Electromagnets; surround; magnetic field
MRI scanning detects ________ atoms, since they occur in abundance in _____ therefore they do in _______ as well
Hydrogen; water; tissue
What are 3 the advantages of MRI?
1) Can visualize the internal structures without risk
2) very effective in differentiating different types of tissue
3) can image any plane in the body
What are the 3 disadvantages of MRI?
1) it is intolerable for subjects who are claustrophobic
2) slow speed
3) expensive
Acoustic analysis looks at _______ __________
Formant frequencies
The first two formant structures determine _____ _______
Vowel identity
What is the physiological basis of vowel production?
Different shapes of the vocal tract
What is the acoustic representation of vowel production?
Formants, particularly F1 and F2
What are formants?
Frequency regions selectively amplified that result in spectral peaks
F1 is the _____ resonance peak and is related to _____ _____
Lowest; tongue height
F2 is the ______ _______ resonance peak and is related to the ______ ___________
Second lowest; tongue advancement
F1 and tongue height are an ________ relationship
Inverse
F2 and tongue advancement are a ________ relationship
Direct
Resonance is __________-selective transmission of _____ energy
Frequency; sound
What type of matter exhibits a resonant frequency?
Any type of matter
