Brain Flashcards
what are the 4 main regions of the brain
cerebrum (cerebral hemispheres
diencephalon
cerebellum
brain stem
what are the functions of the cerebrum
thinking, consciousness, sensory perception, motor movement
what are the functions of the diencephalon
hormonal control, control of smooth muscle, temperature regulation, etc.
these are all the thalami
what are the functions of the cerebellum
balance and equilibrium
what are the functions of the brain stem
control vital centers (breathing, heart rate, blood pressure, etc.)
what are meninges
layer of tissue covering the brain and spinal cord
what are the layers of the meninges
Dura mater
arachnoid
pia mater
what is dura mater made of
fibrous connective tissue
what is the falx cerebri
dura mater extending into the longitudinal fissure of the brain and attaches to the skull at the ethmoid bone
what is the subdural space
the space under the dura mater
what is a subdural hematoma
a hematoma between the dura and the arachnoid
what is an epidural hematoma
a hematoma between the dura and the cranium
what is the arachnoid meningeal layer made of
thin collagen and elastic fibers
what are arachnoid villi
places where arachnoid protrudes through the dura mater into the superior sagittal sinus
what is the subarachnoid space
the space between the arachnoid layer and the pia mater
what is inside the subarachnoid space
cerebrospinal fluid - csf
what is the pia mater made of
fine collagen and elastic fibers that extend into the sulci of the brain
what is cerebrospinal fluid
fluid surrounding the brain and spinal cord
what is cerebrospinal fluid made of
99% water
70% glucose
ions - Mg2+, Na+, Cl-
less protein than blood
what is the purpose of csf
to maintain a proper environment for the brain, regulate intracranial pressure, and has nutrition and excretory functions
where is csf made
in the ventricles of the brain
what two ventricles is the choroid plexus made of
the lateral ventricles
what is the choroid plexus
the lining of the lateral ventricles
what is the function of the choroid plexus
to secrete and recycle csf
what are ependymal cells
cells that line the spaces between the brain and spinal cord
why are ependymal cells important in regards to the flow of csf
the ependymal cells help move the csf aroumd the brain and spinal cord
what is the blood brain barrier
a barrier made of astrocytes that ensures the environment of the brain is controlled
what is a brain ventricle
cavities in the brain that secrete and recycle csf
they also protect the brain by maintaining buoyancy
how many ventricles are there total and name them
lateral ventricles (L/R) - 2
third ventricle - 1
fourth ventricle - 1
there are 4 ventricles total
what is the cerebral aqueduct
the narrow connection between the 3rd nd 4th ventricle
the canal that leads to the 4th ventricle
what ventricles are connected by the cerebral aqueduct
the third and fourth ventricles
what is another name for the cerebral aqueduct
mesencephalic aqueduct
what is the superior sagittal sinus
a large vein that is located in the longitudinal fissure of the brain between the layers of dura mater
what is the flow of csf in order
lateral ventricles
interventricular foramen
third ventricle
mesencephalic (cerebral) aqueduct
fourth ventricle
subarachnoid space OR central canal
arachnoid villi
superior sagittal sinus
what is the term for is more csf is produced than absorbed in the superior sagittal sinus
hydrocephalus
what is the danger of hydrocephalus
the csf isn’t absorbed properly so it causes pressure and bulging on the brain, causing brain damage
what is located in grey matter
unmyelinated axons, neuron cell bodies
what is located in white matter
myelinated axons, axons of neural cell bodies
what is the cerebral cortex
the grey matter on the periphery of the cerebral hemispheres
what are the 3 major types of tracts/fibers in the brain
commissural tracts
association tracts
projection tracts
what is a commissural tract
a tract that foes from right to left and left to right
a tract that connects the left and right brains
what is an association tract
a tract that connects one part of the cortex from another part of the cortex on the same side
what is a projection tract
a tract that runs from the cortex to the lower brain organs
lower brain organs meaning the diencephalon and the brain stem
what do commissural tracts connect
both right and left hemispheres
what do association tracts connect
the gyri and lobes in the same hemisphere
what do projection tracts connect
the cortex with the spinal cord and muscles
are tracts white or grey matter
white matter
what is a gyrus
the folded structures on the brain that allows more cortex for integrative nerve function
what is a sulcus
the indentations in between the gyri in the cerebrum
what is the longitudinal fissure
the large crevice between the right and left cerebral hemispheres
what large vein is located in the longitudinal fissure
superior sagittal sinus
what is the purpose of the superior sagittal sinus
to carry blood to the brain
what is the central sulcus
the groove between the frontal and parietal lobes
what are the lobes of the brain
frontal, parietal, temporal, occipital,
in what lobe is the precentral gyrus located in
the frontal lobe
in what lobe is the postcentral gyrus located in
the parietal lobes
what is the cerebral cortex
the outer portion of the cerebrum
what type of matter does the cerebral cortex consist of
grey matter
which gyrus is responsible for primary motor control
precentral gyrus
what specifically is controlled by the primary motor cortex
the descending motor responses
what is a pyramidal cell
a neuron with a triangular shape
what is meant by the direct motor system aka the pyramidal motor system
the system of both voluntary motor and somatic motor systems
what happens in the precentral gyrus
voluntary motor movement begins here
much of the frontal love contains the premotor cortex for ____________ skills
learned motor skills
what is broca’s are responsible for
motor speech
allows for articulation of words
which gyrus is responsible for somatosensory control/sensory control
postcentral gyrus
in which lobe is the postcentral gyrus
parietal lobes
what specifically is controlled by the postcentral gyrus
ascending sensory intake
sensory input on the right side of the body will travel to the ____________ postcentral gyrus
left post central gyrus
sensory input on the left side of the body will travel to the _________ postcentral gyrus
right
what is wernicke’s area
area in parietal love responsible for general interpretation of what is seen and heard
what will happen if there is damage to the wenicke area
there will be a difficulty in interpreting sounds, words, and more
what will happen if there is damage to broca’s area
a patient will have difficulty speaking. they will know what words they want to say but the words will not come out
what are basal nuclei
grey matter areas of the brain located deep in the brain
what is the function of basal nuclei
send/receive signals from the substantia nigra (midbrain) and cerebral cortex
plays a role in automatic movements (moving arms while walking)
modifies movement to make sure it is appropriate for the task
makes the neurotransmitter dopamine
what is a disease involving the lack of dopamine to the basal nuclei
parkinson’s disease
what happens in parkinsons disease
uncontrolled movements
what is the substantia nigra
the midbrain aka mesencephalin
what does the “right brain” control
left hand control
music/art skills
spatial relationships
insight
what does the “left brain” control
right hand control
speech
numerical and reasoning skills
what is the functino of the diencephalon
homeostasis center deep in the cerebrum
what are the major sections of the diencephalon
thalamus, hypothalamus, epithalamus
what is the thalamus and what are its functions
two oval masses of grey matter
functions in sensory relay (crude sense interpreted), role in memory and emotions in the limbic system, role in motor function
what is the hypothalamus and what are its functions
the homeostasis center - the group below the thalamus
functions in temperature control, satiety (how full you are), smell (mammillary bodies), hormone production (control pituitary gland), control autonomic nervous system, control the limbic system, and circadian rhythm
what is the epithalamus and what are its functions
majorly made of the pineal gland
the gland makes melatonin to aid in the sleep/wake pattern
what is the brain stem and what are its structures
portion connecting the diencephalon, cerebral hemispheres and cerebellum to the spinal cord
includes the mesencephalon, pons, and medulla oblongata
what is the function of the brain stem
aid in vital functions of the body including the breathing center, cardiac center, and more
what are the vital centers of the medulla oblongata
respiratory
cardiac
vasomotor
what are the nonvital centers of the medulla oblongata
sneezing
coughing
vomiting
what are cerebellar peduncles
white matter where information gets to the cerebellum
what type of impulses are carried by tracts that travel thru the pyramids of the medulla oblongata
sensory impulses
are the pyramids locared on the ventral or dorsal side of the medulla oblongata
ventral side of the medulla
what cranial nerves innervate the medulla
CN VIII, IX, X, XI, XII
why might damage to the medulla oblongata be a fatal brain injury
the medulla carries vital centers to include cardiac, respiratory, and vasomotor (blood vessel diameter) so if there is damage, the person may not be able to breathe or their heart might stop
what is the responsibility of the pons
the respiratory center and the bridge for impulses
what is the reticular formation
a network of neurons located in all three parts of the brainstem. it filters sensory information going to the cerebrum and some descending motor impulses
how does the pons connect to the cerebellum
thru the cerebellar peduncles
what cranial nerves innervate the pons
CN V, VI, VII, VIII
what are cerebral peduncles
ventral bulges made by the mesencephalon
this is where voluntary motor tracts are located
what does the substantia nigra do
makes dopamine
what is the corpora quadrigemina
the back/dorsal nclei
what is the superior colliculi and what does it do
a subsection of the corpora quadrigemina that is a reflex center for vision
it aids in blinking and tracking with the eyes
what is the inferior colliculi and what does it do
subsection of the corpora quadrigemina that is a reflex center for hearing
it aids in auditory reflexes and in you turning your head at loud noises
what is the funcitno of red nucleus
subconsious motor information for limb position and background muscle tone along with the cerebellum
red becuase there is a lot of blood supply
what is the reticular activating center
center responsible for wakefulness and sleep and some motor functino
what is the ventral side of the midbrain/mesencephalon
the tegmentum
what are the units of the tegmentum
susbtantia nigra
red nuclei
reticular formations
cerebral peduncles
what are cerebral peduncles
descending voluntary motor tracts in the precentral gyrus
what happens if there is damage to the reticular activating center
coma because it controls sleep and wakefulness
what is the cerebellum and what does it do
portion of the brain that is responsible for balance and equilibrium
functions include muscle coordination and equilibrium
what is the arbor vitae
white matter shaped like a tree in the cerebellum
what are the connections to the brain stem from the cerebellum
superior cerebellar peduncles
middle cerebellar peduncles
inferior cerebellar peduncles
what is proriception
the ability to know where you rbody and body parts are located at all times
what role does the cerebellum play in proriception
the cerebellum deals with balance and equilibrium to help you maintain your balance
if you stick your arm out, you know your arm is out, even without looking
the escalator thing
loss of coordination by the cerebellum leads to ____________
ataxia
what are the units of the limbic system
amygdala (fear/flight or flight)
cingulate gyrus (emotions)
fornix (linking parts of the limbic system together)
hippocampus (memory)
what does the reticular activating center do
helps control the level of activity in the brain, is involved in skeletal muscle control, autonomic functions and pain modulation
what are the neurotransmitters derived from the reticular activating center
serotonin - sleep
norepinephrine - arousal
why is increased intracranial pressure a bad thing
too much pressure can damage the brain and stop the flow of csf and blood
what are the two major arteries that bring oxygen to the brain
carotid arteries
vertebral arteries
what happens in a stroke
something is blocking the blood flow to the brain causing some parts of the brain to be damaged or die.
long term problems include disability, loss of function and death
how many cranial nerves are there
12
what is CN I and what does it do
olfactory
sense of smell to the brain
what is CN II and what does it do
optic
vision form the retina
peripheral vision on same side and regular vision crosses over
(right eye goes left and left eye goes right while also going to same side)
what is CN III and what does it do
oculomotor
moves the eye muscles
what is CN IV and what does it do
trochlear
motor fibers to the superior oblique muscle of the eye only
what is CN V and what does it do
trigeminal
sensory - face sensation of touch
motor - masseter muscle for chewing
what is CN VI and what does it do
abducens
motor fibers to lateral muscles of the eye to look right and left
what is CN VII and what does it do
facial nerve
sensory - 2/3 front tongue for taste
motor - lacrimal glands, salivary glands, skeletal facial muscles
what is CN VIII and what does it do
vestibulocochlear
sensory from internal ear for balance and hearing
balance - vestibular
hearing - cochlear
what is CN IX and what does it do
glossopharyngeal
sensory - taste - posterior 1/3 of tongie
motor - salivary gland and muscles of the pharynx for swallowing and the parotid salivary gland
what is CN X and what does it do
Vagus
sensory - taste
motor - swallowing, voice muscles, autonomic fibers to many abdominal organs (heart, lung, liver)
what is CN XI and what does it do
accessory
motor to sternocleidomastoid and trapezius muscles
what is CN XII and what does it do
hypoglossal
motor to tongue muscles for tongue movement
which cranial nerve sends fibers to muclse that cause facial expressions
CN VII - facial
which cranial nerve helps with balance
CN VIII - vestibulocochlear
which cranial nerve helps with chewing
CN V - trigeminal
which cranial nerve casues tears for crying
CN VII - facial
which cranial nerve slows down the heart rate
CN X vagus
which cranial nerves carry autonomic impulses
III, VII, IX, X
are cranial nerves a part of the CNS or PNS
pns
