Unit 3
sensory areas of cerebral cortex
-conscious awareness of sensation -occur in parietal, insular, temporal, and occipital lobes
auditory association area
-posterior to primary auditory cortex -memories of sounds
somatosensory association cortex 3
-posterior to primary somatosensory cortex -integrates sensory input from primary somatosensory cortex for understanding of object -determines size, texture, and relationship of parts of objects being felt
myelin sheath function
Protect and electrically insulate the axon Increase speed of nerve impulse transmission
microglial cells function
Small cells that wander CNS and replicate in infection Phagocytic cells of immune system Engulf infectious agents and remove debris
overall function of the central nervous system
The central nervous system is the body's processing centre. The brain controls most of the functions of the body, including awareness, movement, thinking, speech, and the 5 senses of seeing, hearing, feeling, tasting and smelling.
primary visual cortex
extreme posterior tip of occipital lobe; receives visual information from retinas
process of spilling acid eyes
eyes goes into lateral geniculate goes into primary visial goes into association cortex goes into posterior association area goes into anterior association area goes into pre motor cortex goes into primary motor cortex goes into midbrain peduncles goes into pyramids goes into spinal cord goes into muscles
ventricles of the brain
filled with cerebrospinal fluid lined by ependymal cells connected to one another and to central caal of the spinal cord
primary somatosensory cortex 4
in postcentral gyri of pareital loves recieves general sensory informarion from skin and prophocerptors of skeletal muscle hoinys and tendos sptail discrimination somatosensory homonuculus
Define depolarization.
increase in membrane potential
electrical properties of neurons 2
ion channels electrochemical gradient
primary motor cortex made up of 2
large pyramidal cells of precentral gyri long axons -pyrmaidls tracts of sinal cords motor homoncols
functional brain systems
limbic and reticular formation
action potentials 7
long distance axon and muscle cells voltage gated all or none dependent on graded principle way neurons send signlas doesnt decay like graded
association cortex provides
meaning
hippocampis
memory
brain stem made up of 3
midbrain pons medulla
What effect on the RMP would increasing the number of K+ ion leak channels in an unstimulated cell's plasma membrane have?
more potassium leake channels means more potassium will leave, making the rmp more negative on the inside
olives of medulla oblongata control
muscle
oligodendrocytes function
myelinate axons in the CNS
primary visual cortex found
occipital lobe
examples of sensory areas of cerebral cortex 8
primary somatosensory cortex somatosensory association cortex visual areas auditory areasa vestibular cortes olfactory cortex gustatory cortex visceral sensory area
visual areas
primary visual cortex and visual association area
What is the function of the primary somatosensory cortex?
processing afferent somatosensory input and contributes to the integration of sensory and motor signals necessary for skilled movement.
transport proteins through
pumps channels
medulla oblangata
pyramids olives
multimodal association areas
receive input from multiple senses and send output to multiple areas, makes up most of the cerebral cortex
What is the function of multimodal association cortex?
receive inputs from multiple sensory modalities.
dendrites function
receive messages from other cells
What is the function of the somatosensory association cortex?
receives tactile information from the body, including sensations such as touch, pressure, temperature, and pain.
axon terminals function
releases neurotransmitters
pons
respiratory center
reticular formation
reticular activating system (cortex)
The normal extracellular (outside the cell) K+ concentration of electrically excitable cells is about 5 mmol/L and the intracellular (inside the cell) K+ concentration is approximately 160 mmol/L. Predict the likely effect on RMP if extracellular K+ concentration climbed to 200 mmol/L.
rmp changes because potassium will be more concentrated on the outside of the ceel and the potassium ions will want to go to the inside
premotor cortex job
send instructions
axon function
send signal from the neuron to the next cell
process to get to the multimodal association area
sensory receptors primary sensory cortex senosry association center multimodal association cortex
graded potentials 5
short distance dendtrites/cell body ligand-gated vary by size triggered by stimulus that opens gated ion channels
process of spilling acid skin
skin (pain) goes into the VPL goes into primary somatic sensoey goes into association cortex goes into posterior association area goes into anterior association area goes into pre motor cortex goes into primary motor cortex goes into midbrain peduncles goes into pyramids goes into spinal cord goes into muscles
What are the two main divisions of the motor division of the peripheral nervous system
somatic nervous system and autonomic nervous system
gray and white matter of the central nervous system
spinal cord central cavitry surrounded by gray matter external white matter composed of myelinated fiber tracts brain similar pattern outer gray matter called cortex inner scatter gray matter necleiamid whute matter
ans process
sypathetic parasympathetic controls smooth cardiac glands
primary auditory cortex found
temporal lobe
primary auditory cortex
temporal lobe interprets ubformation from inner ear as pitch rouchness and location
what is the senosry receptor
thalamus
cerebral cortex 3
thin superficial later of gray matter 40 percent mass of brain sit of consious mind
plasma membrane of nuerons contain
transport proteins
visual association area
uses past visual experiences to interpret visual stimuli
Inside the thalamus 4
vetral posterior lateral vetral anterior/ventral later medial deniuclate lateral geniculate
superior colliculi
visual reflexes
When the resting membrane potential of a neuron reaches threshold what ions channels are opened
voltage-gated sodium channels
four general considerations of cerebal cortex
ymotor sensory and association each hemisphere concerned with contralater side of the body lateralization of cortical function in hempishperes conscious behavior incolbes either the cortex in some way
The puffer fish is considered a delicacy in Japan, but it harbors a deadly neurotoxin, known as tetrodotoxin, or TTX. Prepared by a trained chef this neurotoxin may provide a satisfying tingling sensation with the meal, but in larger doses, the toxin is deadly. TTX binds to and blocks voltage-gated sodium channels so that sodium ions cannot pass through the channels. Using the blank graph below, predict how the action potential of a neuron would be altered by the presence of TTX. Create a line for the action potential graph. A normal action potential is illustrated for reference.
you will still be able to have a graded potential but never an action potential because you wont reach threshold
Assuming TTX impacts all voltage-gated sodium channels in the central nervous system and on skeletal muscles, hypothesize why the toxin is deadly.
you wont be able to sigal anything to happen in your body
What are the two main divisions of the peripheral nervous system?
Autonomic nervous system (ANS): Controls involuntary bodily functions and regulates glands. Somatic nervous system (SNS): Controls muscle movement and relays information from ears, eyes and skin to the central nervous system.
What substance is found in the ventricles of the brain?
Cerebrospinal fluid
What happens as a result of the opening of voltage gated sodium channels?
In the open state, voltage-gated sodium channels form a pore in the cytoplasmic membrane that allows sodium ions to flow into the cell, depolarizing the cell and generating the upstroke of the action potential;
structure of cerebral cortex
Lying right under the meninges, the cerebral cortex divides into four lobes: frontal, temporal, parietal and occipital lobes, each with a multitude of functions. It is characteristically known for its bulges of brain tissue known as gyri, alternating with deep fissures known as sulci
Astrocytes function
Support and brace neurons Anchor neurons to their nutrient supplies Guide migration of young neurons Control the chemical environment
How is the function of the somatic nervous system different than the autonomic?
The somatic nervous system has sensory and motor pathways, whereas the autonomic nervous system only has motor pathways. The autonomic nervous system controls internal organs and glands, while the somatic nervous system controls muscles and movement.
overall function of the peripheral nervous system
Your PNS feeds information into your brain from most of your senses. It carries signals that allow you to move your muscles. Your PNS also delivers signals that your brain uses to control vital, unconscious processes like your heartbeat and breathing.
The sensory division of the peripheral nervous system is also known as the __________ division.
afferent
What is the function of the primary motor cortex?
allows conscious control of precise, skilled, voluntary movements
limbic
amygdala hippocampus
premotor cortex
ataging area for skilled motor activities
inferior colliculi
auditory reflexes
cerebral peduncles
axons of motor neurons
Two divisions of the nervous system
central and peripheral
What are the 3 basic regions of the cerebrum?
cerebral cortex, white matter, basal nuclei
three basic regions of the cerebral hemispheres
cerebral cortex, white matter, basal nuclei
midbrain contains 3
cerebral deuncles superior colliculli inferior colliculi
adult brain regions 4
cerebral hemishperes diencephalon brain stem cerebellum
What are the 4 main regions in the adult brain?
cerebrum, cerebellum, diencephalon, brainstem
Define hyperpolarization
change in the membrane potential to a more negative value
membrane potential changes used as communication signals
changes produce two types of signals-graded and action changes in membrane potentials used as signals to recieve integrate and send information
ependymal cells function
circulate cerebrospinal fluid
hypothalamus jobs 7
control autonomic nervois system emotions body temp food intake water balance and thirst regulate sleep controls endocrine system
frontal eye fluid
control voluntary eye movements
premotor cortex function
controls leabed repetitions or patterbed motor skills coordinates stimularRIOYS or sequential actions controls voluntary actions that depend on secnsory feedback
resting membrane potential definition 2
creator of everything how t stays positive and negative
What structures of a neuron are graded potentials generated in?
dendrites
process of apilling acid ears
ears goes into medial geneciate goes into primary auditory goes into association cortex goes into posterior association area goes into anterior association area goes into pre motor cortex goes into primary motor cortex goes into midbrain peduncles goes into pyramids goes into spinal cord goes into muscles
The motor division of the peripheral nervous system is also known as the __________ division.
efferent
Five lobes of the cerebral hemispheres
frontal, parietal, temporal, occipital, insula
Name the 5 lobes of the cerebral hemispheres.
frontal, parietal, temporal, occipital, insula
Neuron A and Neuron C both fire action potentials every millisecond. How will the firing rate compare to the situation described in Question A. where only Neuron A is firing?
go down because you are releasing more inhibatory neortramirrory not allowing an action potentiL FROM B AND NOT HITTING THRESHOLS
If Neuron C fires every millisecond and Neuron A does not fire any action potentials, what will happen to the firing rate of Neuron B?
goes down or wouldnt fire wouldnt touch threshould making the frequency of action potentials to go own
If Neuron A fires every millisecond and Neuron C does not fire any action potentials, what will happen to the firing rate of Neuron B?
goes up when a is added the esps will be larger going past threshold
cell body function
performs cellular metabolism and receives messages
What is the function of the pre-motor cortex?
planning and movement
where is the primary somatosensory corte found
post central girus
role of ion leak channels in creating the rmp
potassiu will leak out of the cell (a lot) sodiu leake in removing more positive ions from thw inside then brining in will cause a more negative inside
what makes the rmp 3
potassium and sodium leak channels sodium potassium pump negative charged proteins inside
Where in the cerebral cortex is the primary motor cortex found?
precentral gyrus
process to get to cerebellum
premotor primary motor cortec cerebellum
brocas area
presnt in one hemisphere left motor speech area
motor aeas if cereral cortex
primary (somatic) motor cortex in precentral gyrus premotor cortex borcas area frontal eye field
auditory areas
primary auditory cortex and auditory association area
Name the 4 motor areas of the cerebral cortex.
primary motor cortex; premotor cortex; Broca's area; frontal eye field
