CNS Flashcards
how many regions are there?
4
name the regions
cerebral hemispheres
diencephalon
brain stem
cerebellum
gray matter
nonmyelinated
white matter
myelinated
basic pattern
gray matter inside, white matter outside (opposite on cerebrum and cerebellum)
number of ventricles
4
ventricles are lined with
ependymal cells
ventricles are filled with
cerebral spinal fluid
how much mass do cerebral hemispheres take up?
83%
gyri
ridge
sulci
shallow grooves
transverse
separates cerebellum from cerebrum
fissures
deep grooves
lobes
frontal
temporal
occipital
parietal
insula
sulci divide the
lobes
central sulcus divides
frontal and parietal
parieto occipital sulcus
divides parietal and occipital lobe
lateral sulcus
divides right and left hemispheres
3 regions
cerebral cortex - of gray matter
white matter - internally
basal nuclei - deep within white matter
the membrane must depolarize by
15 to 20 MV
for the threshold, Na permeability
increases
Na+ moves _____ K+ moves ______
in, out
AP are self
propogating
AP can only travel
in the forward direction
CNS tells difference of weak and strong based on the
frequency of impulses
refractory periods happen when a neuron cannot
trigger another action potential
during a refractory period, voltage gated na+ channels are
open
refractory periods enforce
one way transmission
relative follows
absolute refractory period
repolarizing is
occuring
threshold is
elevated
stimulus must be ______ to get a new AP
strong
velocity
axon diameter
degree of myelination
continuous conduction
continuous conduction
speed is slow
saltatory conduction
only generated in gaps
electrical signal jumps
cerebral cortex is the site of the conscious mind meaning
awareness
sensory reception
voluntary motor initiation
communication
memory storage
3 types of functional areas
motor
sensory
association
motor
voluntary movement
sensory
conscious awareness of sensation
association
integrate diverse information
lateralization can only occur
in one hemisphere
conscious behavior involves how much of the brain
both hemispheres
where are motor areas located
frontal lobe
primary motor cortex
-located in the precentral gyrus
-pyramidal cells allow precise control of muscle movement
-tracts project down spinal chord
premotor cortex
-helps plan movement
-controls learned, repetitious or patterned motor skills
-coordinates simultaneous or sequential actions
brocas area
left hemisphere
speech/speech production
damage to areas of primary motor cortex results in
paralysis/strokes
sensory areas occur in which lobes
temporal
occipital
parietal
insular
how many sensory areas are there
8
primary visual area
-located at the posterior tip of the occipital lobe
-receives visual info from retina
primary somatosensory
-located in parietal lobe
-sensory info from skin and proprioceptors
- spacial discrimination - ID of body region being stimulated
somatosensory association
-posterior to primary somatosensory cortex
-integrates sensory input in order to understand object
-determines what is being felt (junk drawer)
visual association area
-INTERPRETS visual stimuli
-complex PROCESSING
auditory areas
located near temporal lobes
interprets auditory info
auditory association area
stores memories of sounds
vestibular cortex
conscious awareness of balance
olfactory cortex
smell
gustatory cortex
taste
visceral sensory cortex
internal organs - bellyache
multimodal association areas
-receive input from multiple sensory areas
-sends output to multiple areas
-gives meaning and allows memory storage
-sensations, thoughts, and emotions become conscious
how could you disrupt a neuron?
if sodium channels do not open, sodium cannot get in therefore the neuron will not reach threshold, therefore no action potential will be sent and no message will be sent through the neuron
