Phonatory Physiology, Neuroanatomy, and Differential Diagnosis Flashcards
Glottal Tone Initiation:
5 steps
A. VF approximation
◦ B. Tense and elongate the VF’s
◦ C. Airflow from the lungs
◦ D. Bernoulli effect
◦ E. Vibration entails Bernoulli effect to close VF’s, and a
positive pressure when you wish to open them.
Mechanisms of Vocal Frequency Change
3 factors
Mechanisms of Vocal Frequency Change
◦ Vocal Fold Length and Fundamental frequency
◦ Vocal Fold Mass and Fundamental frequency
◦ Vocal Fold Tension and Fundamental Frequency
Mechanisms of Loudness Change
What makes the loudness mechanism ?
What is sound ?
Mechanisms of Loudness Change
◦ Variation in the size and shape of the vocal tract
◦ Muscular activity in combination with airflows and
pressures.
◦ Vocal intensity measured in decibels of sound pressure
level.
◦ Sound is a pressure disturbance-expect that increased
pressure below the VF’S when eventually released
produces a high intensity (volume).
Mechanisms of quality Variation
What type of control ?
Our voluntary control center of the laryngeal
muscles takes place in the brain.
Many connecting points within the brain:
◦ Cortex-conceptualization, planning and
execution of speech and phonation.
◦ Subcortical areas
◦ Midbrain
◦ Brain stem
Cortex:
Penfield and Roberts identified what ?
Responsible for what ?
Cortex:
Penfield and Roberts (1959) identified 3 major
areas of the cortex responsible for vocalization:
◦ Precentral and postcentral gyrus (Rolandic area)
◦ Anterior area (Broca’s)
◦ Supplementary motor area
Research has shown
Research has shown that vocalization takes place
when certain spots in the discussed areas of the
cortex are stimulated in dominant and non
dominant hemispheres.
Brain Stem
What is in the brainstem that is important for phonation and what does it do?
What type of control and did why ?
The major bilateral structures in the brain stem
responsible in neuro control of phonation include:
◦ Nucleus ambiguus
◦ Nucleus tractus solitarrii
◦ Nucleus parabrachialis
Vagus Nerve cranial nerve 10
What are the branches relevant for phonation?
What does the nerve do ?
Where are bodies if the vagus nerve located ?
Nerve that supplies the larynx and other parts of
the body
◦ Motor and sensory in function
◦ Cell bodies of the vagus located in the nucleus ambiguus.
◦ Major portions of the vagus serving the larynx:
Superior laryngeal nerve-External branch(cricothyroid)
Superior laryngeal nerve-internal branch(mucous
membrane of larynx, true vocal folds)
Vagus Nerve cranial nerve 10
Recurrent laryngeal nerve-(remaining intrinsic
laryngeal muscles)
Differential Diagnosis
Diagnosis
Diagnosis:
Book uses term diagnosis in two ways:
◦ A. process to determine the nature of the problem
◦ B. decision to the end product of the diagnosis process
When we analyze voice problems we must look at:
When we analyze voice problems we must look at:
◦ Statement of the problem
◦ Symptoms
◦ Case history
◦ Signs observed and measured by the SLP
To get this information we need
To get this information we need:
◦ Interview
◦ Medical records
◦ Perceptual characteristics (subjective-perceived by the
listener)
◦ vibratory, acoustic, aerodynamic, and muscle
measurements
◦ Treatment probing
Determine the etiology
Determine the etiology:
◦ Etiology=cause of problem.
◦ Incorrect etiology may result in improper treatment
Symptoms
Symptoms (some symptoms can be verified, some cannot):
◦ Pain on one or both sides of neck (cannot feel pts pain)
◦ Soreness of throat
◦ Hoarseness
Sign
Sign (can be observed or tested):
◦ Hoarseness (low fundamental frequency, reduced variability of fundamental frequency, increased frequency perturbation, increased spectral noise, and large s/z ratio.
◦ Provide objective information-how signs relate to each other and underlying pathology will help SLP and otolaryngologist evaluate its significance.
