what are nerves
collection of axons
another name for sensory
afferent
which direction do sensory nerves move
toward to CNS
another name for motor
efferent
which direction do motor nerves move
away from the cns
what are the two types of motor nerves
somatic and autonomic
where do somatic nerves go
away from the cns to the skeletal muscle
where do autonomic nerves go
away from the cns to the cardiac muscle, smooth muscle and glands
what are the two autonomic nerves called
sympathetic and parasympathetic
what do sympathetic nerves do
increase activity
what do parasympathetic nerves do
decreases activity
how many pairs of spinal nerves are there
31
what is a ganglion
collection of neuron (nerve) cell bodies located outside the cns
what makes up the CNS
brain and spinal cord
the brain has how many major parts
6
the cerebrum is divided by a
longitudinal fissure
what does the longitudinal do to the cerebrum
divides it into 2 cerebral hemispheres
what do each hemisphere have
gyri or gyrus
fissure
sulci
what is a gyri or gyrus
convolution, raises area
what is a fissure
deep furrows
what is a sulci
shallow furrows
what are the major sulci/fissures
central sulcus
parieto-occipital fissure
lateral fissure
another name for central sulcus
fissure of rolando
another name of lateral fissure
fissure of sylvius
what are the five lobes of the cerebrum
frontal
parietal
occipital
temporal
olfactory
what does the precentral gyrus contain
primary motor cortex
what does the parietal gyrus contain
primary sensory cortex
what does the occipital contain
primary visual cortex
what does the temporal contain
primary auditory cortex
what does the olfactory contain
primary olfactory cortex
the two cerebral hemispheres are connected by what kind of matter
white
the two kinds of white mater are
corpus callosum and fornix
the thicker, white part of the matter is the
corpus callosum
the smaller thinner white matter is the
fornix
the cavity of the cerebrum is the
lateral ventricle
how many lateral ventricles are there
2
what are the cranial nerves originating from the cerebrum
I and II
what are cranial nerves I and II
olfactory and optic
areas that moves have a bigger or smaller presentation on the precentral gyrus
bigger
where is the insula
its a lobe that is deep within the brain
what is responsible for the communication between the cerebral areas and between the cerebral cortex and lower cns centers
cerebral white matter
what are the fiber types in cerebral white matter
association, commissural and projection
function of association fibers
connects different parts of the same hemisphere. connect adjacent gyri. bundled into tracts and connect different cortical lobes.
function of commissural fibers
connect corresponding gray areas of the two hemispheres
function of projection fibers
tie the cortex to the rest of the nervous system and the to body receptors and effectors.
what are the three basic regions of the cerebral hemisphere
cerebral cortex, white matter, basal nuclei
location of basal nuclei
island of gray matter situation deep within the white matter
what is considered the executive suite
cerebral cortex
function of cerebral cortex
where our conscious mind is found. it enables us to be aware of ourselves and our sensations, to communicate, remember, understand, and initiate voluntary movements.
each hemisphere is chiefly concerned with the sensory and motor functions of which side of the body
the contralateral side
what are the motor areas
primary motor cortex, premotor cortex, ,broca's area, and the frontal eye field
function of premotor cortex
helps the plan movements
location of brocas area
lies anterior to the inferior region of the premotor area
function of brocas area
special motor speech area that directs the muscles involved in speech production
function of frontal eye field
the cortical region controls voluntary movement of the eyes
where do the sensory areas of the cortex occur
parietal, insular, temporal and occipital lobes
function of primary somatosensory cortex
receive information form the general (somatic) sensory receptors in the skin and from proprioceptors (position sense receptors) in the skeletal muscles, joints and tendons.
which area controls spatial discrimination
primary somatosensory cortex
what are the sensory areas
primary somatosensory cortex, somatosensory association cortex, visual areas, auditory areas,, vestibular cortex, olfactory cortex, gustatory cortex, visceral sensory area
function of somatosensory association
integrate sensory inputs (temperature, pressure and so forth) relayed to it via the primary somatosensory cortex to produce an understanding of a object being felt, it's size, texture and the relationship of its parts
what area perceives upset stomach, full bladder, etc
visceral
which cortex is responsible for taste
gustatory
which cortex if responsible for balance
vestibular
part of the basal nuclei
caudate nucleus, putamen, globus pallidus
function of basal nuclei
plays a role in cognition and emotion
parts of the diencephalon
epithalamus, thalamus, subthalamus, hypothalamus
what contains the pineal gland
epithalamus
function of epithalamus
control of onset of puberty
sleep wake cycle
what is a cluster of nuclei that is a dumb bell shape
thalamus
function of thalamus
synapse of auditory, visual and other sensory impulses.
influences mood
influences body movements associated with emotions
what is connected to the pituitary gland
hypothalamus
function of hypothalamus
produces ADH, Oxytocin and other hormones that control secretion of hormones from the pituitary gland.
controls heart rate, movement of food down the digestive tract, blood vessel diameter.
controls swallowing and shivering
controls body temperature
controls emotions
what cavity is the hypothalamus located in
cavity of diencephalon in the third ventricle
cranial nerves originating from the diencephalon
none
which part of the brain has a roof and a floor
midbrain
what is the roof of the midbrain called
tectum
what does the tectum contain
four neclei bodies, each called colliculs and together called corpora quadrigemia
function of superior colliculus
visual reflex
function of inferior colliculus
hearing reflex
another name for the floor of the miadbrain
tegmuntum
what is the tegmuntum
has two trucks called cerebral peduncle passing through it
the cavity of the midbrain is
cerebral aquedcut
cranial nerves originating from the midbrain
III and IV
what are the nerves of III and IV
oculomotor and trochlear
how many parts of the cerebellum
three
what are the parts of the cerebellum
2 lateral cerebellar hemispheres
2 flocullonodular lobes
1 vermis
function of cerebellum
maintenance of posture
coordination of muscular movements
what is the cavity of the cerebellum
fourth ventricle
cranial nerves originating from the cerebellum
none
function of the pons
relays information from cerebrum and cerebellum
ascending and descending nerve tracts pass through it
has center for sleep
has center for respiration
cavity of pons
fourth ventricle
cranial nerves originating from the pons
V, VI, VII, and part of VIII
names of nerves V, VI, VII, VIII
trigeminal, abducen, facial, auditory
what makes up the brain stem
mid brain, pons and medulla oblongata
what does the medulla oblongata have
2 pyramids and 2 olives
description of pyramids
medial bulges that taper down-contain descending nerve tracts that cross over
description of olives
lateral bulges-contain nuclei of balance
function of medulla oblongata
ascending and descending nerve tracts pass through it
has center for respiration
has center for reflexes-vomiting, sneezing, coughing
controls blood vessel diameter
controls heart rate
cavity of medulla
central canal
cranial nerves originating from the medulla
part of VIII and all of IX, X, XI, and XII
nerves of VIII, IX, X, XI, AND XII
auditory, glossopharyngeal, vagus, accessory, hypoglossal
what is the connective tissue that surrounds the brain and spinal cord
meninges
function of meninges
protection of brain and spinal cord
what are the layers of the meninges
duramater, arachnoid mater and piamter
outermost layer of the meninges
duramater
middle layer of meninges
arachnoid mater
innermost layer of meninges
piamater
which meninges layer is strongest
duramater
what are the tow sublayers of the duramater
periosteal and meningeal
where do the periosteal and meningeal separate
dural venous sinus
what are the spaces of the meninges
extradural, subdural, subarachnoid
another name for extradural
epidural
function of meninges
cover and protect the cns
protect blood vessels and enclose venous sinuses
contain cerebrospinal fluid
forms partitions in the skull
function of the dural venous sinuses
collect venous blood from the brain and direct it into the internal jugular veins of the neck
where does the periosteal layer attach
the inner surface of the skull
what does the meningeal layer form
the true external covering of the brain and continues caudally in the vertebral canal as the spinal dura mater
what separates the two dural maters
dural venous sinuses
purpose of the dural septa
limit excessive movement of the brain within the cranium
what are the three dural septas
falx cerebri
falx cerebelli
tentorium cerebeli
a large sickle shaped fold the dips into the longitudinal fissure between the cerebral hemispheres. anteriorly, it attaches to the crista galli of the ethmoid bone.
falx cerebri
the vermis of the cerebellum
falx cerebelli
fold that extends into the transverse fissure between the occipital lobe of the cerebral hemispheres and the cerebellum
tentorium cerebelli
knoblike projections of the arachnoid mater that protrude superiorly through the dura mater and into the superior sagittal sinus. these absorb cerbrospinal fluid into the venous blood of the sinus
arachnoid villi
watery broth similar in composition to blood plasma, from which it is formed. However, it contains less protein than plasma and its ion concentrations are different
cerebrospinal fluid (CSF)
what forms the CSF
choroid plexuses
total amount of CSF
150ml
how often is CSF replaced
every 8 hours
what are the components of the nervous system
sensory input, integration and motor output
sensory receptors monitor changes to both external and internal stimuli
sensory input
process of interpretation of the sensory stimuli and decision of what needs to be done
integration
effector organ that causes a response
motor output
two types of cells of the nervous system
neuron and neuroglia
function of neuroglia
protect, nourish and insulate the neuron
neuroglia cells in the cns
astrocytes, microglia, ependymal, oligodendrocytes
Two kinds of Neuroglia in the PNS
satelite and schwann
most abundant neuroglia cell in CNS
astrocytes
types of neurons
multipoloar, bioploar, unipolar
most abundant type of neuron
multipolar
neurons especially seen in retina of eye and olfactory mucosa
biopolar
neuron mainly seen in the gangilon
unipolar
two types of neurons based on function
sensory neuron and motor interneuron
most abundant neuron in CNS based on function
motor interneuron