chapter 7 Flashcards
on the ventral side of skull, there is more risk for damage because..
divots and holes. sensitive part of brain
main issue with concussions…
pressure
contra coup hit
when you get hit on one side of the head and the brain gets injured on the opposite side
why are circles used to carve into skulls
symmetry, it won’t all out
ventricular system
fluid filled caverns and canals inside the brain. its extension of neural tube.
gives nutrients to brain
hollow ball of cells
blastula (this is how humans are formed)
endoderm turns into
internal organs
mesoderm
bones and muscle
i you dont seal up on bottom side
spineadephia
if you dont heal up on top side…
anasephly
neurotubes form into
brain and spinal cord
know mammalian brain
enter pic here
dermatomes
what the strip of skin that spinal root is linked to
hindbrain controls..
homeostasis. it controls our physiological needs
cerebellum means..
little brain
what species have the largest cerebellum
humans and birds
cerebellum controls.
accuracy, luidity of fine motor movement, and balance
taxion
disruption of motor function to do goal directed behavior
midbrains purpose helps with..
visual orientation (helps with peripheral vision)
pons
allows for better communication with cerebellum
reticulatar formation
a diffuse network of nerve pathways in the brainstem connecting the spinal cord, cerebrum, and cerebellum, and mediating the overall level of consciousness.
tectum
means roof. it”s in midbrain
what are the two “textum roofs”
superior colliculi
inferior colliculi
what is the super colliculi for
visual orienting
what is the inferior colliculi for
auditory
what is the purpose of the midbrain
to keep us safe
floor of midbrain
tegmentum (motor reflexes)
what is tegmentum used for
motor reflexes
what is the moto reflex used for (when babies fall)
to make you bigger so mom can grab you
test used for infant reflexes
apgar
thalmus looks like..
big lump on brain stem
what part of brain regulates pubetry
hypothalmus
hypothalamus releases..
hormones and oxytocin
what hormone is the mediator of prejudice
oxytocin
hypothalamus sends messages to..
pituitary
hypothalamus does what to hearing / seeing
enhances it
where vision is processed
lateral geniculate nucleus
limbic system allows for..
shortcuts for intuitive responses
what parts of the forebrain supports emotions, learning and movement?
limbic system and basal ganglia
what does basal ganglia mean
bottom and clump of cell bodies
gyrus/gyri means..
bump
sulcus/sulci means…
crack
longitudinal fissure
separates left and right parts of the brain
part of brain with internal map
parietal lobe
contact mediated attraction/contact mediated repulsion
how cells move toward/ move away from certain things
whats the first stage of wiring the brain
generation of neurons from the neural tube
steps of wiring the brain
neurogenesis
migration
differentiation
what trimester does neurogenesis occur
first trimester
what trimester does cell differentiation happen
second
what trimester does neuronal maturation happen
third
why is there so much neurogenesis happen in first trimester
an increase in human growth factor
stages of cell types/maturation
stem
progenitor
blast
specialized
two types of blast cells
neural and glial
arboration
when neurons are trying to connect to ll cells (arborize-uncontrolled growth)
what predisposes cells to migrate to certain cortical locations
subvascular zone
what distinctly differentiates the cortex’s cellular makeup?
organized into layers and grows off of subvacular zone
what acts like a scaffold for new neurons
glial
ventricles are what part of the brain?
the empty spaces
what happens during further differentiation
when cells reach their destination they go from precursor to neuron
they extend their axons to find appropriate target
what begins differentiation
neurites sprouting off cell body
when is the neurons fate determined
before migration
what does architecture depend on
intercellular signals
optic chiasm
where neurons cross left and right eyes
steps of making connections
pathway selection
target selection
address selection
axons and dendritic process appear_____
similar. they are both called neurites in cell differentiation
what is the growing tip called
growth cone
what did hubel and wiesel work on (and got nobel prize)
ocular dominance (whether neurons go to contralateral vs ipsilateral) it showed how cats only respond to certain angels/placements depending on what they were exposed to during the critical period
od
right eye
os
left eye
when do we become accustomed to new angles
critical period/critical wiring
motor visual recalibrations
adjusting speed of walking to make vision go at certain speed
synapse formation in cna steps
insert pic here
part of brain when you make analogies
temporal parietal junction
booba vs keke is based off of..
acceleration in TPJ
basis of synesthesia is located in..
temporal partiaa junction
steps of brain plasticy
arborization
pruning
(neurons that fire together wire together)
what parts of the brain myelinate last
frontal
parietal
Basic organization plan of CNS of call mammals
Telencephalon Diencephalon (thalamus) Midbrain Hindbrain Spinal cord
Rostal most and largest part of the brain
Cerebrum
What are the two cerebral hemispheres separated by
Sagittarius fissure
The berebellum contains as many neurons as____
Both cerebral hemispheres combined
Difference between hemispheres of cerebral hemispheres and cerebellum
Cerebellum-left side controls left side of body and right controls right
Function of brain stem
Relay information from cerebrum to start unaltered ford and cerebellum and Vice Versa
Also where vital functions are regulated (body temp, breathing, consciousness)
Most primitive part of brain.
Central nervous system
Part of nervous system that is encased in bone
Spinal cord and brain
Parts of the central nervous system
Cerebrum
Cerebellum
Brain stem
Spinal chord
How does the spinal cord communicate with rest of body? What are they part of?
Hey though spinal nerves which are part of PNS
Two spinal nerves are dorsal and ventral
What are the two spinal roots?
Dorsal and central (enter pic here)
Two parts of PNS
Somatic pns and visceral pns
Somatic pns
Spinal nerves that inner age the skin joints and muscles that are under voluntary control
Somatic motor axons
Command muscle contraction derived from motor neurons in central spinal cord
Cell bodies of motor neurons lie within CNS and their axons are in PNS
Dorsal root ganglion
Cell body of somatic sensory axons. They lie outside spinal cord
Somatic sensory axons collect information from skin muscles and joints
Somatic sensory axons
Innervate and collect info from skin, muscles, joints and enter the spinal cord via the dorsal root
Visceral pns
Also called autonomic nervous system. Consist of neurons that innervate the internal organs, blood vessels, and glands
Afferent vs efferent axons
Afferent-carry efferent-Cary from
Indicates weather axons are carrying information toward of from a particular point
How many cranial nerves are there
12
They each have a name and number
Some are part of CNS and others are part of PNS
Where do cranial nerves arise from
Brainstem and innervate mostly the head
Do cranial nerves only have one kind of axon
No
Protective layers that make sure brain does not come into direct c bract with bone
Meningies
How many meme goes are there? What are they?
3
Dura mater
Arachnoid membrane
Pia mater
Outermost covering menengie
Dura mater (means hard mother) has leather like consistency.
Forms tough inelastic bag that surrounds BRAIN AND SPINAL CORD
Meningie beneath dura mater. Tell me about it
Arachnoid membrane
(Greek work from spider) resembles spider web
There is no space between dura and arachnoid
What happens if blood vessels from dura rupture, how is it treated?
Blood can collect in between dura and arachnoid (this is called subdural hematoma)
Buildup of fluid in this can disrupt brain function by compressing parts of CNS
Fixed by drilling a hole in skull and draining the blood
Buildup of fluid in subdural space
Subdural hematoma. Caused by rupture of dura mater
Treated by drilling a hole in skull and draining blood
Pia mater
One of the menengies
Thin membrane that adhere closely to the surface of the brain
Marin many blood vessels that ultimately dive into substance of underlying brain
Separated from arachnoid by fluid filled space
What is the pia mater separated by
Fluid filled space called SUBARACHNOID (filled with salty clear liquid called cerebrospinal fluid)
Salty clear liquid that brain floats inside of
Cerebrospinal fluid
Enter pic of menengies
Pic here
Fluid filled caverns and canals inside of brain
Ventricular system
Contains cerebral spinal fluid
What fluid is used in ventricular system
Cerebral spinal fluid (CSF)
What is CSF produced by
Choroid plexus (a special tissue in the ventricles of the cerebral hemisphere)
How does CSF enter the subarachnoid space
Small openings near where cerebellum attaches to the brain stem
What is CSF absorbed by
Arachnoid villi
Hydrocyphalus
When CSF is backed up
Causes brain swelling
More serious in adults than babies since skull cannot expand
Causes severe headache and caused by distention of nerve endings in the menengies
Treatment consist of inserting tube to drain fluid
Clarity
New method to study the brain
Sick brain in solution that repels light absorbing lipids with a water soluable gel
Reveals location of cells deep in the brain
Exposed neurons express green fluorescent protein
Uses information about hydrogen atoms in the brain that respond to perturbations of sting magnetic field
MRI
Computed tomography (CT)
Uses c rays
Showed organization of white and grey matter and position of ventricles
Pet and fmri
Detects changes in regional blood flow and metabolism within the brain
How does the embryo begin
It’s a flat disc with three distinct layers
Endoderm
Mesoderm
Ectoderm
Endoderm
Lining of many internal organs
Mesoderm
Bones of skeleton and muscles
Ectoderm
Nervous system and skin
Neural plate
Changes in part of ectoderm that give rise to nervous system
Early stage of humans (17 days old) that consist only a flat sheet of shells
Formation of neural tube and neural crest
Begins as a then sheet of ectoderm
Forms neural groove
Walls of groove (called neural folds) come together and fuse forming the NEURAL TUBE
buts of neural ectoderm that are pinched off when tube rolls up is called the NEURAL CREST (where pns develops) (somites are mesoderm)
ENTER PIC
When neural tube folds together, some of the ectoderm is pinched off and comes to lie lateral to neural tube..this is called
Neural crest
Where are all neurons within cell body derived from
Neural crest
Process by which the neural plate becomes the neural tube
Neurulation
Happens about 22 days after conception
Process by which structures become more complex and functionally specialized during development
Differentiation
What is the brain derived from
The three primary vesicles of the neural tube (the first step in differentiation of the brain happens at the ROSTAL end and develops the primary vesicles)
Three primary vesicles
Forebrain
Midbrain
Hindbrain
(Enter pic here)
The forebrain vesicles sprout off secondary vesicles which are
Optic vesicle
Telencephalic vesicle
Central structure that remains after security nasty vesicles sprout off forebrain
Diemcephalon
Where do optic nerves and retinas come from
The optic vesicle (it folds in to form optic stalks and optic cups)
These then become the optic nerves and the retinas
Telencephalon
Also called endbrain
CONSIST OF TWO CEREBRAL HEMISPHERES
How do olfactory bulbs develop
Sprout off ventricles that are on ventricle surfaces of cerebral hemispheres
Where are white and grey matter developed
Telencephalon
What is key landmark in adult brain
Paired lateral ventricles(fluid filled space within cerebral hemispheres)
Thirds ventricle (fluid filled space at center of diencephalon)
Corticle white matter
Contains all Axons that run to and from neurons in cerebral cortex
It’s continuous to the internal capsule
Internal capsule
Links cortex within the brain stem, particularly the thalamus
Why is the thalamus referred to gateway to cerebral cortex
Sensory pathways relays in the thalamus
Thalamus sends axons to internal capsule (internal capsule is where cross starts to happen)
Cortical neurons
Received sensory information and forms perception of outside world
Commands voluntary movements
Send axons through internal capsule back to the brain stem
Communicate with basal ganglia
Damage to basal ganglia results in
Disrupting the ability of voluntary movement
Corticle neurons also communicate with neurons of basal ganglia
Hypothalmus
Controls autonomic (visceral) nervous system
Primitive functions-heart rate, blood flow, motivates animals for food, drink and sex drive
Controls fight or flight response
Directs bodily responses via pituitary gland
Parts of midbrain
Tectum (derived from dorsal surface of midbrain vesicle)
Cerebral aqueduct
Constricts CSF (narrow channel)
Connects rostal with third ventricle of the diencephalon
Good landmarker for identifying midbrain
Two parts of the tectum
Superior culliculus
Inferior colliculus
Superior colliculus is also called..
Optic tectum
Optic tectum (superior colliculus)
Controls eye movements
Three important structures in the hindbrain
Pons
Medula oblongata
Cerebellum
CSF tube in hindbrain becomes..
Fourth ventricle
Why are the major white matter systems on each side of the medula called medullary pyramids
When cut in cross section, these bundles of axons appear somewhat triangular in shape