Speech Science Test 2

Central Nervous system (CNS)

brain and spinal cord

Peripheral Nervous System (PNS)

cranial nerves (12 prs), spinal nerves (31 prs)

Neurons

highly specialized structures that receive, process, and transmit information to, from, and within the nervous system

How do neurons function?

They are wrapped together in bundles that form nerve pathways or tracts

Afferent Nerves

Ascending - bringing sensory information to brain, and carry information from sensory receptors

Efferent Nerves

sending motor commands out from brain

Mixed nerves

Some afferent nerves, some efferent nerves bundled together

Interneurons

within the nervous system (communication)

Dermatome

Area of body served by a spinal nerve

Teleceptors

sensory information from distant environment

Eye, Ear

Proprioceptors

position of body in space

Inner ear, muscles, tendons, joints

Chemoreceptors

taste, smell

tongue, nose

Mechanoreceptors

pressure/deformation

tissue, inner ear

Which cranial nerves are used for speech?

Trigeminal Nerve (CN V)

Facial Nerve (CN VII)

Vestibulocochlear

Glossopharyngeal Nerve (CN IX)

Vagus Nerve (CN X)

Hypoglossal Nerve (CN XII)

Trigeminal nerve function

sensory: face

motor: chewing

Facial nerve function

motor: facial expression, sensory: taste

Vestibulocochlear nerve function

sensory: hearing motor: damping for muscles

glossopharyngeal nerve function

Sensory: back of the mouth motor: pharynx

Vagus nerve function

Senory and motor for the body

Hypoglossal Nerve (CN XII)

Controls tongue muscles, which are essential for articulation and speech

dendrites

receive stimuli

soma

generates AP at Axon hillock

axon

transmits impulses

Terminal end button

Synapse

The synapse

junction/space

presynaptic neuron

conducts impulses toward the synapse

synaptic cleft

The narrow gap that separates the presynaptic neuron from the postsynaptic cell.

postsynaptic neuron

transmits impulses away from the synapse

Neurons at rest are

NEGATIVE

How do neurons keep this negative attitude?

Na/K pump is trying to maintain this negative attitude

moves 3 Na IN and 2 K OUT

Electrical synapse

Faster, direct connection of cytoplasms

Less common

Retina, olfactory, cortex

Chemical Synapse

most common, and use neurotransmitters

2 hemispheres of the brain

right and left, cortex/subcortex

brainstem

midbrain, pons, medulla

cerebellum

A large structure of the brain that controls fine motor skills

gray matter (cerebral cortex)

outermost area of the cerebral hemispheres that contains the cell bodies of neurons

LEFT hemisphere

language & Broca's area for speech production

What parts of the brain are involvedin speech and language?

Perisylvian areas, bilaterally

Frontal lobe

motor strip

Broca's area

speech production -formulates language, then sends to motor strip to execute language

Motor strip

muscle movement, voluntary movement

White matter

Blood Supply to the Brain

Middle Cerebral Artery

nutrients to many speech areas

Blood-brain barrier

Keeps brain safe

Astrocytes

take glucose from blood & deliver it to neurons

Oxygen diffuses into CSF

Functional MRI

Functional MRI shows regional cerebral blood flow, where is blood going in the brain

EEG & ERP

Event-related potentials (ERP)

Measure of electrical activity of brain over time, via electrodes on skull

Neurogenic Conditions impacting speech/language

Parkinson's Disease (PD)

Multiple Sclerosis (MS)

Amyotrophic Lateral Sclerosis (ALS)

Alzheimer's Disease

Cerebral Palsy

Traumatic Brain Injury

Motor speech disorders

Dysarthria, Apraxia, Aphasia

Dysarthria

impaired speech production due to motoric disability

Apraxia

impaired speech production despite motoric ability

Aphasia

Impaired speech/language following brain damage CVA (stroke), head trauma, tumor

Respiration

gas exchange between an organism and its environment

speech production requires airstream

Vertebrae

Cervical, thoracic, lumbar, sacrum, coccyx

Pectoral girdle

Clavicle, scapula

Pelvic girdle

illium, ischium, pubis

Soft Tissues

Trachea and bronchial tree

Lungs (asymmetrical, 2 left, 3 right)

Muscles Of Inspiration

diaphragm and external intercostals

Forced expiration

abdominals

Pleural linkage

visceral and parietal with space for pleural fluid

Intrapleural pressure is negative

the lungs are LINKED - they are lifted even though the muscles don't touch them

VC at Rest (automatic)

10%

Boyle's Law

volume is the inverse of pressure

Respiratory measures

Adequate airflow required for normal speech production Spirometer

Inspiratory Muscle Function

diaphragm

lung expansion

Primary muscle of INSPIRATION

Intercostals

Boyle's law (negative pressure, air comes in)

Expiratory Muscle Function

Life breathing: passive - relies on gravity, muscles relaxing, elastic recoil

Speech Breathing

10% inspiration, 90% expiration

Respiratory Pressures

Adequate air pressure required for normal speech

Life breathing

exhalation is passive, but is too fast for making speech

Speech breathing

controlled recoil (checking forces to make sure lungs don't deflate too quickly)

Resting Expiratory Level (REL)

Refers to a state of equilibrium in the respiratory system

Conditions Affecting Speech Breathing

-Aging

-Increased ossification of costal cartilages

-Decreased strength of respiratory muscles

-Loss of alveolar surface tenson

-Decreased lung size

Spastic CP

-HYPERtonic & weak

-shallow inhalations

-forced/uncontrolled expiration

Athetoid CP

- Involuntary movements

- irregular/uncontrolled breathing

Respiratory Disorders

COPD (chronic obstructive pulmonary disease) Difficulty breathing due to bronchitis and/or emphysema

CF (cystic fibrosis) Genetic disorder that primarily affects lungs & breathing

Neuromuscular Disorders

ALS (amyotrophic lateral sclerosis) - death of neurons

Myasthenia gravis - neuromuscular disease; muscle weakness

Spinal cord injury - changes in function (e.g., loss of muscle function)

spinal accessory

larynx and motor muscle near spine

depolarization

The process during the action potential when sodium is rushing in (charge changes) the cell causing the interior to become more positive.

repolarization

Return of the cell to resting state, caused by reentry of potassium into the cell while sodium exits the cell. (Na/K pump)

Synapse

where the nuerotransmitters cross

Neurotransmitters

chemical messengers that cross the synaptic gaps between neurons

dendrite

the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body

How many sodium in and potassium out

3 Na in, 2 K out

action potential

a neural impulse; a brief electrical charge that travels down an axon

Things to talk about in action potential

synapse, neurotransmitter, dendrite, Na/K, depolarization, and repolarization

Pleural Linkage

Result of the 2 pleural linings of the lungs that are attached to other parts that pull the lungs down

visceral pleura

inner layer of pleura lying closer to the lung tissue

parietal pleura

outer layer of pleura lying closer to the ribs and chest wall

How does pleural linkage work?

Visceral (inner) and partial lining (outer) are surrounding the lung, the diaphragm is touching the pariteal lining, the diaphram is going to flatten and pull the lungs down, and volume is going to increase. Boyle's law=pressure and volume are inverse, and air will come in

Life breathing the diaphragm is

relaxing, passive, air pushes out

Speech breathing the diaphragm is

using muscles

Expiratory Muscle Activity (rest, speaking, singing)

Rest: passive (muscles relaxing)

Speaking/Singing: muscle activity

Lung volume % of vital capacity (rest, speaking, singing)

Rest: 10% at VC

Speaking: 25% of VC

Singing: 40% of VC

Inspiration/expiration % (rest, speaking, singing)

Rest: 40% Inspiration, 60% expiration

Speaking/Singing: 10% Inspiration, 90% expiration

Body part at rest air intake

nose

Speaking/singing air intake body part

mouth

CT vs MRI

CT: better at detecting bone, quick, less expensive, xray

MRI: better at detecting soft tissue diseases, long, magnetics

Both brain imaging, used for diagnosis, used in acute phase

Lobes and divisions of the brain functions

Frontal Lobe – Thinking, decision-making, voluntary movement, speech (Broca’s area), personality

Parietal Lobe – Touch, temperature, pain, spatial awareness

Temporal Lobe – Hearing, language (Wernicke’s area), memory, face/object recognition

Occipital Lobe – Vision (color, shape, motion)

Cerebellum – Balance, coordination, motor learning

Brainstem – Breathing, heart rate, digestion

blood-brain barrier

Network of cells (gliall cells) that let certain substances enter the brain tissue and keep other substances out