Learning Objectives 11: Nervous System Flashcards
Describe the levels of organization of the nervous system
Central vs. Peripheral
central=brain and spinal cord
peripheral=everything outside CNS-cranial and spinal nerves
Afferents vs. Efferents
afferent=information coming from periphery and moving toward CNS
efferent=carrying motor information away from central nervous system
Somatic vs. Visceral
somatic=skin/body; things responding to external environment
visceral=internal organs; internal environment
What is the autonomic nervous system? What are the two divisions of the autonomic nervous system?
the combination of sympathetic and parasympathetic nervous systems
sympathetic-fight or flight
parasympathetic-rest and digest
What are dendrites? What are axons?
dendrites=the part of a neuron that collects electrical signals and sends it to the cell body
axons=the long trunk that sends nerve impulses away from the cell body to other neurons
What is the difference between neurons and neuroglial cells?
neurons=nerve cells that conduct electrical impulses
neuroglial cells=neuron support cells with multiple purposes; protecting from disease, helping speed up electrical impulses, getting rid of debris
What is gray matter mostly composed of? What is white matter mostly composed of?
gray matter is mostly cell bodies of neurons
white matter is mostly the myelinated axons of neurons
How is the organization of gray and white matter different in the brain and spinal cord?
in the brain white matter is mostly the center and grey matter mostly line the outside of the brain
in the spinal cord it is the opposite, the outer layer (cortex) is the grey matter and the inside is the white matter
Give the general functions of each of the 8 structures of the brain
cerebrum=higher order processing
corpus callosum=connects cerebral hemisphere and facilitates communication
cerebellum=coordination and voluntary movement
thalamus=relay station for senses-decided where sensory information goes to in the brain
hypothalamus=controls release of hormones from pituitary gland and temperature regulation
midbrain=processing visual and auditory information
pons=relays sensory information from brainstem to cerebellum and thalamus
medulla oblongata=maintain vital body functions etc-breathing
What structures make up the brainstem?
the midbrain, pons, and medulla oblongata
Identify and give the general function of each of the 4 lobes of the cerebrum.
frontal lobe=higher order mental and cognitive functioning, personality, voluntary motor, regulation of emotion and behavior
parietal=somatic sensory processing
temporal lobe=auditory processing
occipital lobe=visual processing
What is Broca’s area? What lobe of the brain is it located in? What type of information does it process?
The area of the brain located on the left frontal lobe that processes speech production
What is Wernicke’s area? What lobe of the brain is it located in? What type of information does it process?
An area of the brain located on the left temporal lobe that is involved with speech comprehension
What is the difference between expressive and receptive aphasia?
expressive=issues with producing speech, damage to broca’s area (left frontal lobe)
receptive=issues with comprehending speech and creating responses, damage to wernicke’s area (located on left Temporal lobe)
What are the meninges? What three layers make up the meninges? What is their function?
connective tissue covering brain and spinal cord (CNS) that are for protection
layers
outermost=duramater
middle layer=arachnoid
inner layer= PIA mater
What is within the subarachnoid space?
filled with cerebrospinal fluid that protects and nourishes the brain
Where do arachnoid granulations extend into?
into the venous sinus
What are dural venous sinuses? What layer of the meninges are they within? What is their function?
They are located in the space created by the outer and inner layer of the dura. Their function is to collect venous blood from the brain and then are drained into the superior vena cava
Why might an individual suffer from an epidural hematoma? How does it develop?
An epidural hematoma is a collection of blood pertaining to above the dura mater. Result from traumatic head injury like falling off a bike-rupture of meningeal artery causing leak of blood causing separation of dura from skull
What causes meningitis? What are the common “hallmark” symptoms of meningitis? What type of meningitis is an urgent medical emergency?
common symptoms are headache,fever, and stiff neck
usually viral, sometimes bacterial infection causing inflammation of meninges
bacterial is more urgent
How does meningococcal bacteria spread? What is the result if meningococcal bacteria infect the meninges? What is the result if meningococcal bacteria infect the bloodstream?
spread by direct exchange of respiratory/throat secretions. The result of infection of the meninges is meningitis, and an infection by this bacteria of the blood stream is meningococcemia
How can you prevent meningococcal disease?
vaccination is the best method of prevention, others are not sharing drinking utensils and other things that enter the mouth with others, washing hands regularly, and be mindful of who you kiss
What type of information is carried in dorsal (posterior) roots?
sensory afferents sent to spinal cord
What is a dorsal root ganglion?
a collection of cell bodies of sensory neurons; part of the peripheral nervous system
What type of information is carried in ventral (anterior) roots?
carries motor efferents away from spinal cord to body and viscera
What type of neurons are found in a spinal nerve?
Spinal nerves have 4 neurons that carry somatic and visceral afferents and somatic and visceral efferents
What is shingles? Explain what causes it and why it only occurs over a specific area of skin.
painful itchy rash caused by the reactivation of the varicella virus(causes chickenpox as well)
the specific area affected is the area enervated by the spinal nerve in which the dormant virus was located and reactivated
What are the five regions of the spinal cord?
cervical
thoracic
lumbar
sacral
coccygeal
Why is the spinal cord shorter than the vertebral column?
it stops growing at around 4 years of age, while the vertebral column continues growing as long as we do
What is the cauda equina? What is it composed of?
the end of the spinal cord-anterior and posterior roots
At what vertebral level does the spinal cord end? What is the end of the spinal cord specifically called?
the conus medullaris
between Lumbar vertebrae L1 and L2
Why is the spinal cord enlarged in both the cervical and lumbar regions?
innervation to upper extremities-cervical
innervation to lower extremities-lumbar
What is the purpose of a lumbar puncture? At what level of the spinal cord is it performed? Why is the level of the lumbar puncture very important?
diagnostic procedure for serious infections like meningitis, CNS disorders, or cancers of the brain or spinal cord
performed between lumbar vertebrae 3 and 4-cerebrospinal fluid is sucked in using an aspiration needle
inserted the needle too high may cause the needle to hit the spinal cord, too low is not possible because the sacral vertebrae are fused together
What is spina bifida? What causes it? What are the different types of spina bifida?
hernia of the meninges and spinal cord, caused by an incomplete formation of the vertebral arch. The root causes are believed to be a combination of genetic and environmental risk factors, possibly a folic acid deficiency
the types from least harmful to most harmful
Spina bifida occulta
small opening in vertebral arch, nothing dangerous is protruding, does not cause many problems
spina bifida cystica
hernia or swelling in the meninges-meningocele filled with fluid
can be easily fixed with surgery
fluid and spinal cord/nerves within a meningomyelocele
may cause severe compromised function of functions controlled by lower nerves
What are the ventricles of the brain? What are they filled with?
they are fluid filled spaces in the brain filled with cerebrospinal fluid
What is the function of CSF? Where is it produced?
fills ventricles of brain and subarachnoid space (produced in ventricles)
supports and cushions brain
sampling for lumbar puncture and other diagnostic procedures to diagnose nervous system disease
What is hydrocephalus? What are two possible causes of hydrocephalus? How is it treated?
condition of water head; back up f fluid causing enlarged brain ventricles and increased pressure on brain structures
two possible causes
problem with CSF drainage to dural sinus from damage to subarachnoid granulations
obstruction of flow of CSF from ventricles of subarachnoid space, may be from tumor or developmental abnormality
treatment is surgically implanting a ventriculoperitoneal shunt to drain excess CSF fluid from ventricles through the abdominal cavity or another area
Label parts of spinal cord (nerves, regions, ect)
Label parts of the brain
