Anatomy, neuroanatomy, and Physiology of the Speech Mechanism Flashcards
When oxygen is needed, what part of the brain fires impulses to the respiratory muscles?
Medulla Oblongata.
Framework of Respiration
inhalation –> chest and lungs expand –> diaphragm lowers –> air flows thru nose and mouth –> air goes down pharynx thru the open vocal folds –> air continues down to trachea and bronchial tubes –> air gets to lungs
When respiratory system is at rest, how much are the lungs inflated?
40%
which lung is shorter, broader and bigger?
the right lung
What are the three structures that are key to adequate respiration?
Lungs: this is where the exchange of gas is accomplished
Bronchi: these are tubes that extend from trachea into lungs, communicate with alveoli that open to tiny air sacks in the lungs
trachea: as person inhales-air goes through larynx to the trachea to the lungs which expand. when exhale, air goes upward through trachea-cartilage rings.connects larynx to the bronchi
internal intercostals
pull ribs down to to decrease the diameter of the thoracic cavity for exhalation
external intercostals
raise the ribs up and out for inhalation
3 biological functions of the larynx
- cough
- close trachea so food doesn’t enter the lungs.
- Adduct VFs to build up pressure for lifting
what are the Intrinsic muscles of the larynx
thyroarytenoid lateral cricoarytenoid transverse aryetenoid oblique arytenoid cricothyroid posterior cricoarytenoid
What muscle makes up the vocal folds
vocalic muscle
thyroarytenoid
which muscle lengthens and tenses the vocal folds?
cricothyroid
Which muscle increases medial compression of the vocal folds?
lateral cricoarytenoid
What muscle increases pitch?
cricothyroid
What is the only abductor of the vocal folds?
posterior cricothyroid
what are the adductor muscles of the vocal folds
lateral cricoarytenoid
transverse arytenoid
oblique arytenoid
which muscles depress the larynx?
(4) thyrohyoid omohyoid sternothyroid sternohyoid
what muscles elevate the larynx?
(6) digastric geniohyoid mylohyoid stylohyoid hyoglossus genioglossus
What are the three Layers of the vocal folds?
- epithelium
- Lamina propia
- Vocalic muscle -thyroarytenoid - body
what are the three layers of the lamina propia
- superficial
- intermediate
- deep lamina propia
What is the cover?
the cover is the epithelium and the superficial layer and much of the intermediate layer of the lamina propia
What is the body of the vocal fold
the remainder of the intermediate layer , the deep layer and the thyroarytenoid muscle
What is the cover body theory of phonation
the cover vibrates while the body is stationary
what is composed of a ring of connective tissue and muscle extending from the tips of the arytenoids to the larynx
aryepiglottic folds
What are the functions of the aryepiglottic folds
they seperate the larngeal vestibule from the pharynx and help preserve the airway
what folds usually compress during coughing or heavy lifting?
ventricular, false folds
What is the myoelastic- aerodynamic theory
the vocal folds vibrate due to the forces and pressure of the air and the elasticity of the vocal folds
Myoelasticity: once the VF have been forced apart, they begin to recoil back to midline, due to their natural elasticity. (elastic recoil- similar to the lung-thorax unit)
bernouli effect
air travels towards less pressure
what direction does the mucosal wave travel
back to front
The primary cortical areas involved in speech-motor control
primary motor cortex
brocas area
somatosensory cortex
supplementary motor cortex
function of the cerebellum
regulates motor movement
coordination
what branch of the superior laryngeal nerve innervated he cricothyroid muscle?
the external branch of the SLN
what are the 3 branches of the Vagus nerve
superior laryngeal
recurrent laryngeal
pharyngeal
What happens if there is damage to the superior laryngeal branch?
difficulties managing the pitch
What happens if there is damage to the recurrent laryngeal branch?
paralysis of the vocal folds
What happens if there is damage to the pharyngeal
hypernasality
what branch innervates the cricothyroid?
superior laryngeal
what branch innervates all intrinsic muscles of the larynx beside the cricothyroid?
recurrent laryngeal branch
What are the resonators that modify laryngeal tone?
pharynx
nasal cavity
oral cavity
What are the muscles needed for velopharyngeal closure.?
Tensor veli palatini.
Levator veli palatini.
Palatoglossus.
Palatopharyngeus.
what is the primary elevator of the velum?
levator veli palatini
what tenses the velum and dilates the eustachian tube?
tensor veli palatini
What are the two functions of the muscles of the mouth?
- chewing food
2. opening and closing mouth
What is the primary muscle of the lips?
orbicularis oris muscle
What muscle are the cheeks primarily made of?
buccinator
What nerves primarily supplies the facial muscles
buccal branches and mandibular marginal branch of the facial nerve (VII)
What do the intrinsic muscles of the tongue do?
shorten and turn up
what do the extrinsic muscles of the tongue do?
bulk tongue, depress, down and retract
What are the cranial nerves most associated with articulation?
trigeminal V facial VII Vagus X Spinal accessory VI hypoglossal VII
pneumonic for remembering the cranial nerves
On Old Olympus’ Towering Top, A Finn and German Viewed Some Hops
What cranial nerve functions as sensory for the face and motor for the jaw?
Trgeminal V
Taste sensation to anterior 2/3 of the tongue
Facial VII
If damage to this nerve theres a mask like facial expression
Facial VII
Nerve primarily for balance and equilibrium
Acoustic VIII
Lesions on this nerve create difficulty in swallowing, unilateral loss of the gag reflex, and loss of taste in the posterior 2/3 of the tongue
Glossopharyngeal IX
Lesions to this nerve can result in tongue paralysis, diminished intelligibility and swallowing problems.
Hypoglossol XII
What are the three key structures of the brain stem
midbrain, pons and the medulla
contains descending motor fibers and is involved with hearing and balance. houses the nuclei for the trigeminal V and facial nerve VII
The Pons
most important part of the brainstem for speech production
the medulla
pyramidal tracts start here
the medulla
lesions here, result in unusual body posture, dysarthria, changes in body tone, and dyskinesias that interfere with a persons ability to walk, speak and many other activities
Basal Ganglia
damage to this part of the brain causes ataxia
cerebellum
Area around this fissure are critical in speech language and hearing
sylvian fissure
What lobe is important in planning, executing and attention
the frontal lobe
which lobe is important in perception and processing of visual, tactile and proprioceptive inso
parietal lobe
think right hemisphere disorder
lobe that houses auditory skills
temporal lobe
what is located on the the precentral gyrus and controls voluntary movements of the skeletal system on the opposite side.
primary motor cortex/motor strip
Wernickes area is located in what lobe?
temporal lobe
what is the direct motor activation pathway that is primarily responsible for facilitating voluntary muscle movements
the pyramidal system
The pyramidal system is composed of what two tracts
corticospinal and corticobulbar
where do the projection fibers of the corticospinal and corticobulbar tract originate?
cerebral cortex
corticospinal is contralateral of ipsilateral
contralateral
Which tract from the pyramidal system is critical to speech production
corticobulbar
cerebral ventricles are filled with
cerebral spinal fluid
Function of Cerebral spinal fluid is
nourish the the neural tissue, remove waste product, cushion the brain and regulate intracranial pressure
there are ___ cerebral ventricles
4
(2) lateral (biggest)
the third
and the fourth
How many layers protect the brain and what are they called?
3 the meninges
describe the three meninges
- dura =outermost, thick and tough
- arachnoid = spider web =semitransparent, thin delicate, weblike, CSF fills the space between arachnoid and pia matter
- Pia matter= delicate thin membrane that adheres to the brain surface like plastic wrap,
Major blood suppliers of the brain =
the aorta, vertebral arteries, carotid arteries, and the circle of willis
damage to the middle cerebral artery may result in:
strokes, aphasia
What will happen if an artery is blocked above the circle of willis?
brain damage, because the brain has no alternate source of blood
What will happen if an artery is blocked below the circle of willis?
brain damage may be minimal because alternate channels may be available
Which pyramidal tract is more of the indirect activation system?
extrapyramidal
it helps maintain posture and tone
what cranial nerves innervate the pharynx
IX and X
glossopharyngeas and Vagus
What type of neuron carries signals away from the brain?
efferent