Intro to nervous Quiz 2 Flashcards
what is the central nervous system?
brain and spinal cord
functions in the integration of information - the brain is also the site of centers for intellect, emotions, behaviour and memory
what is the parasympathetic nervous system?
the peripheral nervous system connects the central nervous system to sensory receptors, muscles and glands
PNS is subdivided into:
somatic nervous system (SNS)
autonomic nervous system (ANS)
further subdivided into sympathetic division and parasympathetic division
c. enteric nervous system (ENS) – the brain of the gut
what are the two subdivisions of the efferent neurons of the peripherlal nervous system?
i) somatic motor division - controls skeletal muscles
ii) autonomic division - controls contraction and secretion in the various internal organs.
what are the 3 divisions of afferent neurons in the peripheral nervous system?
i) somatic sensory division
ii) autonomic sensory division
iii) enteric sensory division
what does white matter consist of?
concentration of myelinated axons; the myelin imparts a white color
what does grey matter consist of?
clusters of nerve cell bodies, dendrites, axon terminals, unmyelinated axons, and/or neuroglia; greyish color due to lack of myelin and presence of Nissl Bodies (ribosomes)
what is the orientation of grey matter and white matter in the spinal cord?
inner grey matter shaped like a butterfly & outer white matter
what is the orientation of grey matter and white matter in the brain?
opposite orientation; thin outer layer of grey matter & inner white region with nuclei of grey matter found in concentrations
what are nuclei?
masses of cell bodies and dendrites deep within the brain
what is the brain?
-registers sensations, analyses them, makes a decision, and initiates an action.
-also sites of the centres for intellect, emotions, behavior and memory
what is the cerebrum?
largest portion of the brain
what is the cerebral cortex?
outer gray matter (cell bodies, dendrites, unmyelinated axons, neuroglia)
well developed in humans where it expands and wraps around the midbrain
divided into left and right hemispheres
highly folded to accommodate an increased number of interneurons
what are the 4 lobes of the cerebrum?
frontal lobes: personality, intelligence, judgment, language Posterior part of the frontal lobe contains the motor cortex
parietal lobes: language and somatosensory
temporal lobes: hearing, language, and smell
occipital lobes: interpretation of visual stimuli
what are the functional areas of the cerebral cortex?
sensory areas - interpret sensory input
motor areas- determine the motor output
association areas- emotions, reason
what is the inner white matter?
-groups of myelinated axons called tracts
-convey information from one part of the brain to another
-include corpus callosum- “which communicates between the right and left hemispheres
what are the basal ganglia?
-involved in the control of large, automatic muscle movements and muscle tone
-cells of basal ganglia lose function with Parkinson’s
leads to shaking loss of facial expression and arm swing
what is the limbic system?
-emotional brain - pain, pleasure anger
-includes the amygdala. important in emotional response to stimuli like fear.
-note: hippocampus campus is important for the creation of new memories. these memories may be destroyed by alzeihmers
what is in the diencephalon?
thalamus and hypothalamus (pituitary gland)
what is the thalamus?
-major relay station for sensory impulses to sensory areas of the cerebral cortex from the spinal cord and brainstem
-contribute to motor function from the cerebellum and basal ganglia to motor areas of the cerebral cortex
-also relays impulses between different areas of the cerebrum
what is the function of the Pituitary Gland and Hypothalamus?
Both are involved in hormone secretion and storage
-pituitary gland releases hormones and is subdivided into the anterior pituitary and posterior pituitary each releasing different hormones
-hypothalamus is the communication center between the endocrine system and the nervous system; regulates the release of hormones from the pituitary gland
-Both work together to regulate hunger, thirst, sexual response, pleasure, body temperature (thermostat), and the relaxation state of the body versus the flight-or-fight response
what is the cerebellum?
-involved in unconscious regulation of balance and some locomotory movements such as hand-eye coordination
-involved posture and balance
what is the brainstem?
-midbrain, pons, and medulla oblongata
-three regions are involved in relaying nerves to and from the spinal cord to the brain
-Location of the nuclei of cranial nerves
what is the medulla oblangata?
-thickened stalk at the base of the brain which controls subconscious activities such as respiration, blood pressure, heart rate
-Damage to this area of the brain during a stoke leads to death
-Location of the reticular activating center that wakes up your cerebrum each morning
what are the functions of the spinal cord?
- integrates simple responses to certain stimuli (reflexes)
- relays information to and from the brain
what is the spinal cord composed of?
-Composed of outer white matter and inner gray matter (opposite to the brain);
-white matter contains myelinated axon tracts that ascend with sensory information or descend with motor information
-Gray matter possess many interneurons which synapse with sensory and motor neurons as well as other interneurons
what are reflexes?
fast, automatic, pre-programmed responses to internal or external stimuli
They control some skeletal muscle actions, breathing rate, heart rate, and secretions from sweat glands
May be learned or inborn
what are spinal reflexes?
the most basic form of response to stimuli and does not require brain input
what are the basic components of a reflex arc?
Requires: sensory organ or affector sensory neuron interneuron motor neuron effector such as muscle or gland
what are somatic reflexes?
external stimuli
effectors are skeletal muscles
i.e. stretch reflex, flexor or withdrawal reflex
what are autonomic reflexes?
internal stimuli
effectors are smooth muscle and glands
i.e. blood pressure, respiration rate, defecation
what are meninges?
connective tissue coverings of the brain and spinal cord
what are the 3 layers of meninges?
Dura Mater - tough, superficial layer containing venous sinuses draining the brain
- Arachnoid - middle layer, beneath which is found cerebrospinal fluid (in the subarachnoid space)
- Pia Mater - delicate layer with blood capillaries adhering to the brain’s surface
what is the somatic nervous system?
Somatic sensory neurons (afferent neurons) convey information from sense organs of the skin, head, body wall, and extremities
Somatic motor neurons (efferent neurons) convey information to skeletal muscles only, therefore responses are voluntary (conscious)
what are the two divisions of the autonomic nervous system?
Sympathetic and parasympathetic divisions of the autonomic nervous system work together to maintain homeostasis (feedback systems)
describe the sympathetic division.
Nerve impulses of this division promote energy expenditure
ie. fight-or-flight-or-freeze response
increased heart rate and respiratory rate
glucose formation from glycogen (glycogenolysis)
nerves arise from the thoracic and lumbar regions of the spinal cord (thoracolumbar outflow)
describe the sympathetic division.
Nerve impulses of this division promote energy expenditure
ie. fight-or-flight-or-freeze response
increased heart rate and respiratory rate
glucose formation from glycogen (glycogenolysis)
nerves arise from the thoracic and lumbar regions of thbe teh e spinal cord (thoracolumbar outflow)
describe the sympathetic division.
Nerve impulses of this division promote energy expenditure
ie. fight-or-flight-or-freeze response
increased heart rate and respiratory rate
glucose formation from glycogen (glycogenolysis)
nerves arise from the thoracic and lumbar regions of the spinal cord (thoracolumbar outflow)
describe the parasympathetic division.
Nerve impulses from this division promote energy conservation, relaxation response
ie. rest and digest/feed and breed
Salivation / Lacrimation (tearing) / Urination /
Digestion (includes the storage of energy: lipid and glycogen synthesis) / Defecation
decreased heart rate and respiration rate
nerves arise directly from the brain and from the sacral region of the spinal cord (craniosacral outflow)
an important parasympathetic nerve is the vagus nerve
what are visceral sensory neurons?
(afferent neurons) conduct information from receptors of the viscera (internal organs) to the central nervous system
what are visceral motor neurons?
(efferent neurons) conduct impulses from the CNS to smooth muscle, cardiac muscle, and glands
These motor responses are not under conscious control (involuntary); control heart rate, blood pressure, respiratory rate, digestion, excretion, glandular organs, and smooth muscle of blood vessels
what is the enteric nervous system?
“brain of the gut”
-once considered part of the autonomic nervous system
-considered an independent division that communicates with the central nervous system via parasympathetic and sympathetic fibers
Involves the involuntary enteric plexuses of many neurons that innervate the wall of the gut along its entire length
Sensory neurons of the enteric nervous system monitor the stretching of the gut walls and the chemical composition of the contents of the gut
Motor neurons of the ENS innervate the gut wall and stimulate smooth muscle contractions and innervate glands to regulate the production of secretions or gut hormones
what are cranial nerves?
arise from the brain directly and do not travel in the spinal cord
what are nerves?
bundles of axons (both sensory and motor) surrounded by connective tissue coverings
-can be dissected
what are nerve branches that leave the spinal cord called?
rami
what are the dorsal rami?
supplies dorsal portions of trunk
what are the ventral rami?
supplies ventral portions of the trunk and limbs
what are rami communicantes?
autonomic nervous system branches
what is the meningeal branch?
supplies vertebral column components
what are plexuses?
networks of ventral rami that join with adjacent ventral rami to form the final nerves that supply skeletal muscles and glands
what are the 4 principal plexuses?
- cervical plexus
- brachial plexus
- lumbar plexus
- sacral plexus
what is Alzheimer’s?
Progressive senile dementia due to widespread deterioration of brain tissue with a variety of signs
Loss of memory of recent events, confusion, violent mood changes, and loss of ability to read, talk, eat, walk
what is Amyotrophic Lateral Sclerosis (ALS or Lou Gehrig’s Disease)?
Central nervous system degeneration of motor neurons only
Results in atrophy of skeletal muscles, weakness, fatigue, and spasms
Massage is indicated
what is bells palsy?
Flaccid paralysis of one half of the face due to inflammation or damage to the facial (VII) nerve
One side of the lip droops, no expression, and unable to close the eyelid, possible pain, and hypersensitivity to sound
Massage indicated
what is carpal tunnel?
Irritation of the median nerve in the wrist where it passes under the transverse carpal ligament
Pain, tingling, and weakness in the index finger, middle finger and thumb, and possibly forearm
Massage may be indicated
what is cerebral palsy?
A group of disorders diagnosed in early childhood characterized by impaired motor function and possibly cognitive and sensory dysfunction
Brain damage in utero, during birth, or early infancy
Hypertonic or hypotonic muscles, poor coordination and often display random, involuntary movements
Massage indicated
what is a cerebrovascular accident?
“strokes”
-Ischemic Stroke - deprivation of oxygen to brain tissue associated with blood clots that dislodged from another location called emboli
-Hemorrhagic Stroke - due to bleeding in the brain associated with a ruptured artery – aneurysm
-Signs of a stroke include unilateral (one-sided) loss of sensation, paralysis, jumbled speech
eg. Stroke in the left cerebral hemisphere leads to loss of function and sensation on right side as well as speech and language problems
absolute CI- get them to a hospital!
what is epilepsy?
A chronic disorder characterized by recurrent seizures, which are excessive discharges in cerebral neurons leading to transient impairment or loss of consciousness
Severe symptoms include loss of consciousness, a tonic (rigid) phase, and clonic (shaking phase)
what are headaches?
Migraines are unilateral, throbbing headaches associated with vascular changes within the brain brought on by different triggers
Massage is contraindicated during a migraine attack
Tension headaches are usually bilateral and steadily painful and respond well to massage
what is a herniated disc?
Protrusion of the intervertebral disk which puts pressure on the nerve root or other structures
Symptoms include shooting pain, numbness, muscle weakness eg. sciatica
massage indicated if not too painful
what is herpes zoster (shingles)?
Reoccurrence of the virus that causes chickenpox which had laid dormant in cell bodies of sensory neurons of one nerve until the immune system is compromised
Painful blisters unilaterally in one dermatome
Massage contraindicated in acute
state, but indicated in recovery
what is meningitis?
Inflammation of the coverings of the brain or spinal cord caused by bacteria or viruses
The Cardinal sign is a stiff neck, which can lead to death
Get the patient to a physician
what is multiple sclerosis?
Autoimmune attack of the myelin covering of motor and sensory axons within the central nervous system
Variety of symptoms including progressive loss of vision, sensory and motor function
Massage indicated in subacute stages (remission)
what is Parkinson’s disease?
Progressive degeneration of dopamine (neurotransmitter) liberating cells (of the substantia nigra in the midbrain) that act on the basal ganglia
Signs and symptoms include shuffling gait, loss of balance, loss of automatic muscle movements such as arm swing, mask-like expression, resting tremor (pill-rolling tremor)
Massage indicated
what is peripheral neuropathy?
Usually bilateral damage to peripheral nerves leads to stocking and glove loss of sensation (paresthesia) or burning (dysesthesia) and loss of movement (paralysis)
Due to systemic disorders such as diabetes, alcoholism, lupus
Massage indicated
what is polio?
Viral infection of motor neurons in the spinal cord leading to weak muscles and possibly paralysis; had pretty much been eradicated due to polio vaccines. Was making a comeback, and is again being pruned back, only 3 countries in the world have active polio cases in the last three years
Can lead to death via paralysis of the diaphragm (iron lung)
Does not affect sensation so massage is very appropriate!
what is post-polio syndrome?
Many people who had polio recover as unaffected motor neurons grew new axon collaterals to the muscles that lost their motor neurons
However, with age, these axon collaterals are “pruned back” and the muscle again loses innervation
Signs and symptoms are the same – weak muscles
Massage indicated
what is Raynaud’s syndrome?
Temporary loss of blood supply to fingers, toes, nose, ears, or lips leading to color changes in the skin and possible numbness or tingling
Massage indicated if there is no underlying pathology
what are sleep disorders?
Many different sleep disorders including insomnia, sleep apnea (stopping breathing), restless leg syndrome, narcolepsy (falling asleep at inappropriate times), circadian rhythm disruption (shift work)
This leads to excessive daytime sleepiness, weakened immune system, impaired memory, and concentration, and increased risk of accidents
massage indicated – correct any mechanical problems, reduce sympathetic response
what are spinal cord injuries?
Injuries to the vertebral column and/or spinal cord which lead to complete or incomplete loss of motor, sensory and/or autonomic function at the level of the lesion and below
Quadriplegia (paralysis of arms and legs) if spinal cord severed T1 or above
Paraplegia (paralysis of legs only) if spinal cord severed T2 or below
massage indicated if sensation intact
what is thoracic outlet syndrome?
An entrapment syndrome involving pressure on the brachial plexus and possibly the subclavian artery
Shooting pain, weakness, numbness, paresthesia, and loss of color in the affected arm
If caused by muscle tightness, massage is indicated
