Anatomy, Neuroanatomy, and Physiology of the Speech Mechanism (Chapter 1)

Question 1

What supplies the energy for speech? It is the exchange of gas between an organism and its environment. It is also called breathing and involves the cycle of inhalation (inspiration) and exhalation (expiration). It involves the lungs, bronchi, trachea, spinal column, sternum, and rib cage. The medulla oblongata in the brainstem fires impulses to the respiratory muscles.

Answer 1

Respiration

Question 2

What includes voicing with the structures and processes that help produce voice?

Answer 2

Phonation

Question 3

What is the modification of the voice produced at the laryngeal level, due to the dynamics of the various supralaryngeal cavities and structures? It is the modification of laryngeal tone by selective dampening or enhancement of specific frequencies. The resonant frequency is the frequency at which a cavity best vibrates and is dependent on the size and shape of the cavity. The resonators that modify laryngeal tone are the pharynx, the nasal cavity, and the oral cavity.

Answer 3

Resonation

Question 4

What is the production of speech sounds in isolation as well as in connected speech? It is the movement of speech structures to produce speech sounds. It may also imply saying something clearly.

Answer 4

Articulation

Question 5

inhalation > chest and lungs expand > diaphragm lowers > air flows in through the nose and mouth > air goes down the pharynx and between the open vocal folds > air continues downward through the trachea and bronchial tubes > air reaches final destination of the lungs

Answer 5

Framework of Respiration

Question 6

Where is the exchange of gas in respiration accomplished? They should be soft, spongy, porous, elastic, and pink. They are located in the thoracic cavity.

Answer 6

Lungs

Question 7

What are the tubes that extend from the lungs upward to the trachea? They are composed of cartilaginous rings bound together by fiberelastic tissue. They subdivide into bronchioles, forming what is known as the bronchial tree. They ultimately communicate with alveolar ducts that open into tiny air sacs in the lungs.

Answer 7

Bronchi

Question 8

What is the tube through which air goes into the lungs? It is about 11 centimeters long and is formed by approximately 20 rings of cartilage.

Answer 8

Trachea

Question 9

What consists of 32-33 individual vertebrae?
7 cervical vertebrae
12 thoracic vertebrae
5 lumbar vertebrae
5 sacral vertebrae
3-4 coccygeal vertebrae

Answer 9

Spinal Column

Question 10

What is located on the superior, anterior thoracic wall? It is also called the breastbone. It is made up of three parts.
Manubrium - the uppermost segment of the sternum and provides the attachment for the clavicle and the first rib.
Corpus - the body of the sternum.
Xiphoid process - a small cartilaginous structure found at the bottom of the body of the sternum.

Answer 10

Sternum

Question 11

What is the thoracic cage? It consists of twelve pairs of ribs that articulate posteriorly with the vertebral column and anteriorly with the sternum to form a cylindrical structure. It houses and protects organs such as the heart and lungs.

Answer 11

Rib Cage

Question 12

What is the floor of the chest cavity? It is a thick, dome-shaped muscle that separates the abdomen from the thorax. It plays a major role in breathing and is considered the primary muscle of inspiration. Muscle fibers insert into the central tendon and contract to pull the central tendon down and forward to expand the thoracic cavity.

Answer 12

Diaphragm

Question 13

What houses structures such as the intestines, liver, and kidneys? Various abdominal muscles are critical in providing support for breathing.

Answer 13

Abdomen

Question 14

What are the muscles between the ribs which are critical for respiration? The 11 paired internal intercostals pull the ribs downward to decrease the diameter of the thoracic cavity for exhalation, and the 11 paired external intercostals raise the ribs up and out to increase the diameter of the thoracic cavity for inhalation. The external intercostals and other inspiratory muscles also perform a checking action to control the flow of air leaving the lungs during speech.

Answer 14

Intercostal Muscles

Question 15

The serratus posterior superior, levator costarum brevis, levator costarum longis, and external intercostal muscles are all involved in…

Answer 15

Rib Cage Elevation

Question 16

Three of the key neck muscles are the sternocleidomastoid, the trapezius, and the scalenes. The sternocleidomastoid elevates the sternum and thus, indirectly, the rib cage. The trapezius controls the head and elongates the neck, thus indirectly influencing respiration. The scalenes stabilize and rotate the head. These muscles are attached to the first two ribs, and therefore indirectly enlarge the vertical dimension of the thorax.

Answer 16

Accessory Muscles of the Neck

Question 17

What do the two posterior thoracic muscles involved in respiration do? The subcostal muscle depresses the thorax. The serratus posterior inferior muscles, when contracted, pull the rib cage down and thus aid in exhalation.

Answer 17

They support exhalation

Question 18

Most muscles involved with breathing assist with inhalation. However, muscle action is also needed for exhalation of air. These muscles include the latissimus dorsi, rectus abdominis, transverse abdominis, internal oblique abdominis, and quadratus lumborum.

Answer 18

Abdominal Muscles of Expiration

Question 19

What lies at the top of the trachea in the anterior portion of the neck and houses the vocal folds, which vibrate to produce voice? It produces sound that is shaped into speech. It is a valving mechanism that opens and closes. It is commonly known as the voice box. It also closes the trachea so that food and other substances do not enter the lungs, produces the cough reflex to expel foreign substances that accidentally enter the trachea, and closes the vocal folds to build subglottic pressure necessary for physical tasks such as excretion and lifting of heavy items.

Answer 19

Larynx

Question 20

What vibrates to produce speech? They adduct (move toward the midline) and abduct (move away from the midline) as they vibrate.

Answer 20

Vocal Folds

Question 21

What floats under the mandible, or lower jaw? The muscles of the tongue and various muscles of the mandible, skull, and larynx are attached to this.

Answer 21

Hyoid Bone

Question 22

What is the leaf-shaped piece of cartilage medial to the thyroid cartilage and hyoid bone? It is a protective structure. During swallowing, it drops to cover the orifice of the larynx.

Answer 22

Epiglottis

Question 23

What is the largest laryngeal cartilage and forms the anterior and lateral walls of the larynx? It protects the larynx. It is open posteriorly and has two pairs of horns, known as cornu.

Answer 23

Thyroid Cartilage

Question 24

What is linked with the thyroid cartilage and the paired arytenoid cartilage? It completely surrounds the trachea and is larger in the back than in the front.

Answer 24

Cricoid Cartilage

Question 25

What are the small, pyramid-shaped cartilages connected to the superior posterior cricoid through the cricoarytenoid joint, which permits sliding and circular movements? Many intrinsic laryngeal muscles connect to the vocal process and the muscular process. The vocal folds are attached to the arytenoids at the vocal process. Muscles that both abduct and adduct the vocal folds attach to the arytenoids at the muscular process.

Answer 25

Arytenoid Cartilages

Question 26

What are the small, cone-shaped cartilages that sit on the apex of the arytenoids? They assist in reducing the laryngeal opening when a person is swallowing.

Answer 26

Corniculate Cartilages

Question 27

What are the tiny cone-shaped cartilages that are located under the mucous membrane that covers the aryepiglottic folds? They serve to stiffen or tense the aryepiglottic folds.

Answer 27

Cuneiform Cartilages

Question 28

What are the muscles that are primarily responsible for controlling sound production? They are the thyroarytenoid, lateral cricoarytenoid, transverse arytenoid, oblique arytenoid, cricothyroid, and posterior cricoarytenoid.

Answer 28

Intrinsic Laryngeal Muscles

Question 29

These muscles are paired and each one is attached to the thyroid and arytenoid cartilages and is divided into two muscle masses: the internal thyroarytenoid and the external thyroarytenoid.

Answer 29

Thyroarytenoid Muscles

Question 30

What is the primary portion of the thyroarytenoid muscle, which vibrates and produces sound? It is generally referred to as the vocalis muscle, or more commonly, vocal folds.

Answer 30

Internal Thyroarytenoid

Question 31

These muscles include the lateral cricoarytenoid, transverse arytenoid, and oblique arytenoid. They act to bring the vocal folds together. The lateral cricoarytenoid increases medial compression of the vocal folds by rotating the arytenoids medially.

Answer 31

Adductor Muscles

Question 32

What is the muscle attached to the cricoid and thyroid cartilages? It lengthens and tenses the vocal folds, resulting in pitch change.

Answer 32

Cricothyroid Muscle

Question 33

Most intrinsic laryngeal muscles are innervated by the _____________(RLN) branch of cranial nerve X, the vagus nerve. The RLN supplies all motor innervation to the interarytenoid, posterior cricoarytenoid, thyroarytenoid, and lateral cricoarytenoid muscles. It receives all sensory information below the vocal folds.

Answer 33

Recurrent Laryngeal Nerve (RLN)

Question 34

The Cricothyroid is innervated by the external branch of the ___________________(SLN) branch of the vagus. The SLN has internal and external branches. The internal branch receives all sensory information from the larynx, and the external branch supplies motor innervation solely to the cricothyroid muscle.

Answer 34

Superior Laryngeal Nerve (SLN)

Question 35

What is the name of the small opening that forms when the vocal folds are abducted? It is the name of the (opened) space between the vocal folds.

Answer 35

Glottis

Question 36

What muscles have the primary function of supporting the larynx and fixing its position? They have one attachment to a structure within the larynx and one attachment to a structure outside the larynx. All extrinsic muscles are attached to the hyoid bone and lower or raise the position of the larynx within the neck.

Answer 36

Extrinsic Laryngeal Muscles

Question 37

What muscles attach above the hyoid bone and have the primary function of elevation of the larynx? These muscles are the digastric, geniohyoid, mylohyoid, stylohyoid, hyoglossus, and genioglossus.

Answer 37

Elevators (Suprahyoid Muscles)

Question 38

What muscles attach below the hyoid bone and have the primary function of depressing the larynx? These muscles are the thyrohyoid, omohyoid, sternothyroid, and sternohyoid.

Answer 38

Depressors (Infrahyoid Muscles)

Question 39

These have three layers:
(a) the epithelium, or outer cover
(b) the lamina propria, or middle layer
(c) the vocalist muscles, or body, which provides stability and mass

Answer 39

Vocal Folds

Question 40

What is composed of a ring of connective tissue and muscle extending from the tips of the arytenoids to the epiglottis? They separate the laryngeal vestibule from the pharynx and help preserve the airway.

Answer 40

Aryepiglottic Folds

Question 41

The ______________ vibrate only at very low fundamental frequencies and usually not during normal or typical phonation. They compress during such activities as coughing and lifting heavy items.

Answer 41

Ventricular (False) Vocal Folds

Question 42

This theory states that the vocal folds vibrate because of the forces and pressure of air and the elasticity of the vocal folds. The air flowing out of the lungs is temporarily stopped by the closed vocal folds. This builds up subglottal air pressure, which eventually blows the vocal folds apart. During this process, the folds are set into vibration, as well. The air then moves with increased velocity through the glottal opening. As the air moves swiftly through the open, but still somewhat constricted, vocal folds, the pressure between the edges of the vocal folds decreases, and, consequently, the folds are sucked together. This cycle of opening and closing is repeated more than 100 times per second during vocalization.

Answer 42

Myoelastic-Aerodynamic Theory

Question 43

This occurs when the velocity of a gas or fluid increased when it passes through a constriction, decreasing the pressure of the gas or fluid. In phonation, it is caused by the increased speed of air passing between the vocal folds. The resulting decrease in pressure between the vocal folds causes the “sucking” motion of the vocal folds toward one another.

Answer 43

Bernoulli Effect

Question 44

During this action, the cover (epithelium and superficial lamina propria, also called Reinke’s space) and the transition (intermediate and deep layers of the lamina propria) over the vocalist muscle slide and produce a wave. This wave travels across the superior surface of the vocal fold about two-thirds of the way to the lateral edge of the fold. Without this wave, there is no vibration and thus no phonation.

Answer 44

Mucosal Wave Action

Question 45

What functions to regulate motor movement? It is critical in the control of speech movement. It is key to the coordination of the laryngeal muscles for adequate phonation. It is also key to the affection function of other speech systems, such as respiration.

Answer 45

Cerebellum

Question 46

Key neuroanatomical structures involved in ______________ include cortical areas, the cerebellum, and cranial nerves VII (facial nerve) and X (vagus nerve).

Answer 46

Vocalization

Question 47

What is part of the upper airway, extending from the nasal cavity to the vocal folds? It is located superiorly and posteriorly to the larynx. Its size and shape are modified by the position of the tongue in the mouth and the vertical positioning of the larynx in the neck.

Answer 47

Pharynx

Question 48

What has an important role in resonation? Only three sounds in English are produced with nasal resonance. During the production of those sounds, the soft palate (velum) is relaxed and lowered, coupling the nasal and oral cavities; they are not separated from one another.

Answer 48

Nasal Cavity

Question 49

This structure is elevated and retracted for all oral sounds in English. The raising and the retraction during the production of those sounds help make contact with the posterior pharyngeal wall, separating the oral cavity form the nasal cavity. The cavities are thus uncoupled, and the sounds are produced primarily with oral resonance.

Answer 49

Velum

Question 50

What is the primary resonating structure for all English sounds, except /m/, /n/, and /ng/?

Answer 50

Oral Cavity

Question 51

What theory states that energy from the vibrating vocal folds (the source) is modified by the resonance characteristics of the vocal tract (the filter)? It depicts the vocal tract as a series of linked tubes: the oral cavity, the pharynx, and the nasal cavity. The vocal folds generate a voicing source. This voicing source is routed through the vocal tract, where it is shaped into speech sounds. Those speech sounds may be vowels when the source is phonation, and consonants when the sources include the turbulence of friction or combinations of turbulence and voicing. Structures within the oral cavity are shaped and moved to provide specific resonance for each sound.

Answer 51

Source Filter Theory

Question 52

This cavity is divided into three segments:
(a) The Laryngopharynx, which begins immediately superior to the larynx and ends at the base of the tongue
(b) The oropharynx, which extends up to the soft
(c) The nasopharynx, which ends where the two nasal cavities begin
The laryngopharynx and the oropharynx add resonance to the sounds produced by the larynx. However, the nasopharynx adds noticeable resonance only to the nasals, /m/, /n/, and /ng/.

Answer 52

Pharynx

Question 53

What is formed by the joining of cranial nerves X and XI and supplies the upper pharyngeal musculature?

Answer 53

Pharyngeal Plexus

Question 54

What is the flexible muscular structure at the juncture of the oropharynx and the nasopharynx? It is also called the velum. It is located in the posterior area of the oral cavity and hangs from the hard palate. It is a dynamic structure of muscles that can be elevated or lowered. It is composed of a number of muscles; the musculus uvulae, levator veli palatini, the tensor veli palatini, the palatoglossus, and the palatopharyngeus muscles.

Answer 54

Soft Palate

Question 55

What is the small, cone-shaped structure at the tip of the velum?

Answer 55

Uvula

Question 56

What is the sphincter-like action that closes the nasal port? This occurs when the soft palate is raised and retracted and the muscles of the pharynx move inward to meet the muscles of the soft palate.

Answer 56

Velopharyngeal Closure

Question 57

What forms the roof of the mouth and the floor of the nose? It is part of the maxillae. They are the largest bones in the face and form the entire upper jaw. The front portion of the maxillary bone is called the premaxilla. The premaxilla houses the four upper front teeth known as the incisors. The portion of the maxillary bone that forms three-quarters of the hard palate is called the palatine process; it is the floor of the nasal cavity. The palatine process consists of two pieces of bone that grow and fuse at the midline during the fetal stage. The outer edges of the maxillary bone are called the alveolar process, which houses the molar, bicuspid, and cuspid teeth. Posteriorly, the maxillary bone joins with the palatine bone. It comprises the remaining quarter of the hard palate and the soft palate attaches to it.

Answer 57

Hard Palate

Question 58

What houses the lower teeth and forms the floor of the mouth? It is known as the lower jaw and is an important facial bone. It is formed by the fusion of two bones in the midpoint of the chin but is considered to be one bone in adults. The alveolar arch is the part of the mandible that houses the teeth. It is attached to the temporal bone of the skull by a joint called the temporomandibular joint. The muscles of the mandible serve two major functions: (a) opening and closing of the mouth, and (b) chewing food.

Answer 58

Mandible

Question 59

What structure has the primary function of mastication? They also help produce some speech sounds. Deciduous teeth are temporary teeth that appear in a baby, usually around 6 - 9 months of age. Babies normally have 20 deciduous teeth, 10 in each arch. Adults have 32 teeth, 16 in each arch.

Answer 59

Teeth

Question 60

What refers to the way the two dental arches come together when a person “bites down?” It is normal if (a) the upper and lower dental arches meet each other in a symmetrical manner, and (b) if the individual teeth in the two arches are properly aligned.

Answer 60

Occlusion

Question 61

What refers to deviations in the positioning of individual teeth and the shape and relationship of the upper and lower dental arches?

Answer 61

Malocclusions

Question 62

What structure plays an important role in eating and speech production? The taste buds help people taste their food, and the muscles move food around in the oral cavity for efficient mastication and swallowing. Movements of this structure are critical to articulation. For example, tongue movement is necessary to produce several classes of sounds, including the linguadentals, lingua-alveolars, and lingua-palatal. The tongue also constricts the air passage to create the friction needed to produce fricatives. Anatomically, the tongue is divided into four major parts: tip, blade, dorsum, and root.

Answer 62

Tongue

Question 63

What is the thinnest and most flexible part of the tongue and plays an important role in articulation?

Answer 63

Tip (of the tongue)

Question 64

What is a small region adjacent to the tip; in a resting position, it is the portion of the tongue that lies just inferior to the alveolar ridge.

Answer 64

Blade (of the tongue)

Question 65

What is the large area of the tongue that lies in contact with both the hard and soft palates? This is the area of the tongue that is visible upon protrusion.

Answer 65

Dorsum (of the tongue)

Question 66

What is the very back and bottom portion of the tongue?

Answer 66

Root (of the tongue)

Question 67

What structure connects the mandible with the inferior portion of the tongue? This band of tissue may stabilize the tongue during movement.

Answer 67

Lingual Frenulum

Question 68

These muscles are within the tongue itself. They are responsible for fine movements.

Answer 68

Intrinsic Muscules of the Tongue

Question 69

These muscles connect the tongue to a structure outside the tongue. They are named based on the structures they attach to (e.g., hyoglossus connects the hyoid bone to the tongue). These muscles are responsible for gross movement of the tongue.

Answer 69

Extrinsic Muscles of the Tongue

Question 70

What muscle forms the bulk of the tongue and allows it to move freely? It has both anterior and posterior fibers.

Answer 70

Genioglossus Muscle

Question 71

The primary muscle of the lips is the orbicularis oris muscle. The cheeks are primarily composed of the buccinator muscle, a large flat muscle whose inner surface is covered with a mucous membrane. Most of the facial muscles are innervated by either the buccal branches or the mandibular marginal branch of cranial nerve VII, the facial nerve.

Answer 71

Lips and Cheeks

Question 72

What is the study of neurological disorders and diseases and their diagnosis and treatment?

Answer 72

Neurology

Question 73

What is a branch of neurology concerned with the study of structures of the nervous system?

Answer 73

Neuroanatomy

Question 74

What is a branch of neurology is concerned with the study of the function of the nervous system?

Answer 74

Neurophysiology

Question 75

What neurons carry sensory impulses from the peripheral sense organs toward the brain? They are also called sensory neurons.

Answer 75

Afferent Neurons

Question 76

What neurons transmit impulses away from the CNS or the brain? They are also called motor neurons. These neurons cause glandular secretions or muscle contractions (movement).

Answer 76

Efferent Neurons

Question 77

What cells do not transmit nerve impulses and mainly support and protect the nerve cells? These types of cells include astrocytes, oligodendroglia, ependymal cells, and microglia. The glia cells of the peripheral nervous system (PNS) are called Schwann cells and satellite cells.

Answer 77

Glial Cells (or Neuroglia)

Question 78

What is the most important type of nerve cells? They receive information from other neurons, process that information, and then transmit the information to other neurons. They have two parts: (a) nerve fibers and (b) the soma, or cell body, which contains the nucleus.

Answer 78

Neurons

Question 79

What is the core of the cell body called?

Answer 79

Nucleus

Question 80

What are the short fibers that extend from the cell body? They receive neural impulses generated from the axons of other cells, and they transmit those impulses to the cell body.

Answer 80

Dendrites

Question 81

What are longer fibers and have terminal, or end, buttons at the tip? They send out impulses generated within the neuron; these impulses are sent away from the cell body to other neurons. End buttons contain neurotransmitters. The end button of one neuron either makes close contact with or actually touches the dendrite of another neuron.

Answer 81

Axons

Question 82

What is the white insulating sheath around many axons, especially the larger axons of the CNS and those in the PNS? It has breaks at the junction between the cells to facilitate the impulse transfer.

Answer 82

Myelin

Question 83

What is an organization of nerves according to specific spatial, structural, and functional principles? The peripheral, autonomic, and central nervous systems are often collectively referred as the _______________.

Answer 83

Nervous System

Question 84

What allows neurons to communicate with each other through junctions? An axon branches out into several smaller fibers, which form terminals. These terminals connect to a ___________, although this neural junction includes a small gap or space. Thus, a ___________ consists of the terminal button of one neuron, the receptive site of another neuron, and the synaptic cleft or space between the two.

Answer 84

Synapse

Question 85

What is a chemical process of information exchange at the level of the synapse?

Answer 85

Neural Transmission

Question 86

What is a chemical contained within the terminal buttons that helps make contact between two cells by diffusing itself across the synaptic space? Such diffused neurotransmitters become bound to receptors in the postsynaptic membrane. The diffused neurotransmitter may cause the inhibition or excitation of the next neuron. Dopamine and acetylcholine are two important neurotransmitter sin the motor system.

Answer 86

Neurotransmitter

Question 87

What is the most common type of neuron in the nervous system? They link neurons with other neurons and play an important role in controlling movement.

Answer 87

Interneurons

Question 88

What are a collection of nerves that are outside the skull and spinal column? These nerves carry sensory impulses, which originate in the peripheral sense organs, to the brain, and motor impulses, which originate in the brain, to the glands and muscles of the body. The PNS contains three types of nerves: the cranial, the spinal, and the autonomic. There are 12 pairs of cranial nerves and 31 pairs of spinal nerves.

Answer 88

Peripheral Nervous System (PNS)

Question 89

What structures emerge from the brain stem and are attached to the base of the brain? They are part of the lower motor system, and they receive much of their innervations from the corticobulbar tract of the pyramidal system. They are numbered according to the vertical order in which they exit from the skull. There are 12 pairs.

Answer 89

Cranial Nerves

Question 90

Cranial nerve I is a sensory nerve originating in the nasal cavity. It is involved with smell.

Answer 90

Olfactory Nerve

Question 91

Cranial nerve II is a sensory nerve originating in the retina. It is involved with vision.

Answer 91

Optic Nerve

Question 92

Cranial nerve III and Cranial nerve IV are motor nerves that originate in the midbrain area and innervate muscles corresponding to eye movement.

Answer 92

Oculomotor Nerve and Trochlear Nerve

Question 93

Cranial nerve VI is a motor nerve that controls eye movement.

Answer 93

Abducens Nerve

Question 94

Cranial nerve V is a mixed (both motor and sensory) nerve. Its sensory fibers are composed of three branches: The ophthalmic, maxillary, and mandibular branches.
The ophthalmic branch has sensory branches from the nose, eyes, and forehead.
The maxillary branch has sensory branches from the nose, upper lip, maxilla, upper cheek area, upper teeth, maxillary sinus, nasopharynx, and palate.
The mandibular branch has sensory branches from the mandible, lower teeth, lower lip, tongue, part of the cheek, and part of the external ear. It transmits tactile, pain, and temperature stimuli from the anterior two-thirds of the tongue.
The trigeminal nerve is bilaterally innervated, so unilateral upper motor neuron lesions minimally impact motor function. Damage to cranial nerve V may also cause trigeminal neuralgia (sharp pain in the facial area).

Answer 94

Trigeminal Nerve