Term
Are the dendrites of sensory neurons short or long? |
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Definition
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Term
are the axons of sensory neurons short or long? |
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Definition
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Term
where are sensory nerve cell bodies housed? |
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Definition
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Term
are the dendrites of motor neurons short or long? |
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Definition
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Term
are the axons of motor neurons short or long? |
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Definition
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Term
where and on what do motor neurons synapse |
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Definition
motor neurons send information down spinal cord, synapse on alpha motor neuron |
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Term
most neurons are what kind of neuron? |
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Definition
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Term
what is the function of astrocytes? |
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Definition
secretion and absorption of neural transmitters, maintenance of the blood-brain barrier |
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Term
astrocytes are a subtype of what type of cell? |
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Definition
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Term
where do astrocytes like to be? |
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Definition
around synapses made by neurons |
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Term
after coming in through the dendrites, where does information in a neuron go to be integrated? |
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Definition
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Term
once summation of information gets to a certain point within the cell, what will happen |
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Definition
it will generate an action potential that can go down the axon and to the terminal synapses |
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Term
what is used to transfer electrical signals through neurons? |
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Definition
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Term
what are some important positive ions in the nervous system |
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Definition
sodium, potassium, calcium |
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Term
what is an important negative ion in the nervous system? |
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Definition
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Term
do proteins have + or - charge? |
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Definition
different proteins are +, some are - |
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Term
describe the nerve cell membrane in one word |
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Definition
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Term
what is the resting potential of the cell? |
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Definition
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Term
are the neuron's membrane's ion channels open or closed at rest? |
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Definition
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Term
what is the major ion inside the neuron at rest? |
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Definition
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Term
what is the major ion outside the cell at rest? |
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Definition
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Term
what is inside the cell that gives it a negative resting charge? |
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Definition
negatively charged proteins |
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Term
what maintains the charge imbalance at rest? |
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Definition
sodium potassium pump that actively transport ions against their concentration gradients |
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Term
what do we call the places where ions are passed across the cell membrane? |
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Definition
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Term
what kinds of stimuli will cause the membrane potentials to change |
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Definition
chemical or physical stimuli |
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Term
what happens when the membrane ptoentials change? |
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Definition
the sodium and potassium channels each open, allowign sodium to enter and potassium to exit |
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Term
what happens as a result of the change in concentrations as potassium exits the cell and sodium enters the cell following a stimulus to the neuron? |
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Definition
the change in concentration gradient produces a local passive current that is propagated along the membrane |
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Term
what causes the local passive current caused by the change in concentration gradient to decay? |
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Definition
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Term
what does it mean if you are farther away in the dendrite from the axon hillock? |
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Definition
you might have less effect on the transmission of an impulse |
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Term
how does sodium entering the neuron change its potential? |
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Definition
sodium entering the cell makes the membrane potential more positive |
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Term
what membrane potential must be reached to trigger an action potential? |
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Definition
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Term
what is the response to an action potential? |
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Definition
all soidum channels open and rapid depolarization occurs as soidum enters the cell |
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Term
what happens when the membrane potential reaches + 50 mV? |
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Definition
sodium channels close and potassium channels open so that potassium can exit the cell and restore resting membrane potential |
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Term
How is the neuron restored to its original distribution of ions? |
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Definition
sodium ions are pumped out of the cell and potassium ions are pumped into the cell |
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Term
what is the general path of information transmission in the CNS? |
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Definition
synapse on dendrite -> local depolarization goes through cell body -> goes into axon hillock -> travels down axon -> into terminal synapse -> into post synaptic membrane of the next target cell |
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Term
is the dendrite presynaptic or postsynaptic? |
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Definition
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Term
will an excitatory post synaptic potential depolarie or polarize the cell? |
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Definition
EPSP deploarizes the cell |
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Term
will an inhibitor post synaptic potential depolarize or polarize the cell? |
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Definition
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Term
what if a neuron receives both EPSPs and IPSPs? |
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Definition
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Term
can an axon from a neuron give both IPSPs and EPSPs |
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Definition
no, all synapses from one axon is either all EPSP or all IPSP |
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Term
what will happen if you can depolarize the cell to -55 mV? |
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Definition
you can generate an action potential |
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Term
what is the mechanism for an IPSP? |
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Definition
moving potassium out of the cell to make it more negative |
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Term
what ions can be added to the neuron to hyperpolarize it |
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Definition
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Term
how many synapses can you have on each neuron? |
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Definition
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Term
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Definition
the passive spread of current inside a neuron |
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Term
what is neural integration |
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Definition
ability of neurons to process info, store/recall it, and make decisions. Example: you have knee pain, your CNS senses the pain, your CNS reduces the amount of work that you can do |
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Term
where in the neuron do synaptic potentials sum? |
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Definition
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Term
if you are a distal dendrite far from the axon hillock, are the synapses you get necessarily going to make an action potential? |
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Definition
your synapses will have to travel farther to get to axon hillock. The EPSPs all have to sum to -55mV at the axon hillock to make an action potential |
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Term
describe the temporal strategy for summation of EPSP and IPSP |
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Definition
increase the frequency of signal |
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Term
describe the spatial strategy for summation of EPSP and IPSP? |
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Definition
increase the number of sources |
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Term
what happens when you stretch a muscle? |
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Definition
the muscle spindle excites its own alpha motor neuron and makes it want to contract |
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Term
how does increasing frequency increase the likelihood of an excitatory response? |
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Definition
before the EPSP can decay, the nexxt stimulus arrives. This continues until we reach threshold |
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Term
what happens at the synapse when the action potential arrives? |
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Definition
local depolarization causes clacium channels ot open and to let in clacium |
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Term
when calcium enters the presynaptic nere ending, what happens? |
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Definition
clacium causes vesicles filled with neurotransmitter to migrate towards the presyaptic membrane and bind with it |
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Term
what happens once the neurotransmitter binds with the presynaptic membrane? |
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Definition
the neurotransmitter is released into the synaptic cleft |
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Term
what happens when the neurotransmitter is released intot he synaptic cleft? |
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Definition
it diffuses and binds with receptors and receptor cahnenel membranes |
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Term
if neurotransmitters were continually in the synaptic cleft, what would happen? |
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Definition
the postsynaptic channels would always be stimulated so that the membrane potential couldn't restabilize |
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Term
what are the 3 ways that neurotransmitters are deactivated? |
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Definition
degradation, reuptake, autoreceptors |
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Term
what is degradation of a neurotransmitter/ |
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Definition
enzymes located int eh synaptic cleft break down the neurotransmitter so that it has no effect on the receptor/receptor channel of the postsynaptic cells |
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Term
what is neurotransmitter reuptake? |
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Definition
allowing the neurotransmitter to reenter the presynaptic cell through membrane channels for reuse |
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Term
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Definition
receptors for specific neurotransmitters that are located on the presynaptic membrane and respond to neurotransmitter release by decreasing further release of the neurotransmitter |
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Term
what is long term potentiation |
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Definition
increase sensitivity of senapses so that a constant level of presynaptic stimulation is converted into a larger postsynaptic output |
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Term
how long can longterm potentiation last? |
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Definition
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Term
what is LTP associated with? |
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Definition
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Term
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Definition
how a trained person will sweat faster during exercise becaause their synapses are sensitive so that a stimulation will more quickly produce a larger postsynaptic output |
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Term
what is the role of neurotransmitters? |
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Definition
to inhibit or excite the postsynaptic cell by changing its membrane potential |
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Term
what determines whether a neurotransmitter is excitatory or inhibitory? |
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Definition
the neurotransmitter + its receptor site |
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Term
what is the most common neurotransmitter in the brain? |
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Definition
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Term
is glutamate excitatory or inhibitory |
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Definition
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Term
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Definition
an excitatory neurotransmitter found in the spinal cord |
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Term
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Definition
a neurotransmitter that can be either excitatory or inhibitory |
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Term
is dopamine more commonly excitatory or inhibitory |
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Definition
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Term
what is the main focus of the locus coeroleous |
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Definition
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Term
what is the main neurotransmitter of the locus coeroleous |
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Definition
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Term
what is the primary neurotransmitter at the neuromuscular junction? |
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Definition
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Term
is acetylcholine excitatory or inhibitory |
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Definition
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Term
is serotonin excitatory or inhibitory |
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Definition
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Term
is norepinephrine excitatory or inhibitory? |
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Definition
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Term
what is the extrapyramidal pathway |
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Definition
projections between the cortex and striatum |
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Term
what functions is the basal ganglia associated with? |
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Definition
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Term
what functions is the forebrain associated with? |
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Definition
cognition, reward, emotional behavior |
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Term
what functions is the tubero-infundibular system concerned with? |
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Definition
control of the hypothalamic-pituitary endocrine system |
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Term
what neurotransmitter affects the basal ganglia? |
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Definition
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Term
what neurotransmitter affects the mesolimbic forebrain/ |
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Definition
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Term
what neurotransmitter affects the tubero-infundibular system? |
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Definition
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Term
what neurotransmitter affects the locus coeroleus? |
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Definition
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Term
what is the function of the locus coeroleus? |
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Definition
automatic movements: fight or flight |
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Term
what neurotransmitter affects the raphe nuclei? |
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Definition
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Term
to what other parts of the brain does the locus coeruleus connect? |
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Definition
many other areas, particularly areas that bring in and process information, especially sensory information |
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Term
what does the locus coeroleus secrete? |
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Definition
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Term
what is the pacemaker of the brain? |
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Definition
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Term
what does the locus coeroleus do in times of stress? |
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Definition
increases arousal and vigilance and modulates action of the autonomic nervous system |
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Term
for what functions is the locus coeruleus critical? |
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Definition
nuermous functions including stress, attention, emotions, motivtion, decision making, or learning and memory |
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Term
what is the major inhibitory neurotransmitter of the brain? |
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Definition
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Term
what happens when you take drugs that block GABAa receptors? |
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Definition
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Term
what happens when you take drugs that activate GABAa receptors? |
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Definition
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Term
blocking GABA b receptors can help with what? |
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Definition
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Term
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Definition
a major inhibitory neurotransmitter in the spinal cord |
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Term
where do we see GABAergic inhibition? |
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Definition
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Term
about how much of the inhibitory synapses in the brain are GABA mediated? |
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Definition
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Term
what types of simple circuits regulate how and if signals are transmitted? |
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Definition
post synaptic excitation, disfacilitation, postsynaptic inhibition, disinhibition, presyanptic inhibition |
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Term
what is another name for presynaptic inhibition |
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Definition
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Term
what is post-synaptic inhibition |
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Definition
that is the regular depolarization of a cell from an excitatory synapse. It creates an excitatory post synaptic potential |
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Term
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Definition
when an inhibitory cell prevents an excitatory cell from exciting the target cell |
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Term
what is post synaptic inhibition |
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Definition
using an inhibitory cell on the target cell to inhibit the target cell |
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Term
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Definition
using an inhibitory cell to inhibit the inhibitory cell on the target cell so that the inhibitory cell on the target cell is less likely to fully inhibit the target cell |
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Term
what is an example of a post synaptic exicitation |
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Definition
a muscle spindle will activate its own alpha motor neuron through post synaptic excitation. |
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Term
what is an exaple of post synaptic inhibition |
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Definition
a muscle spindle will deactivate the alpha motor neuron of an antagonist muscle by using an inhibitory interneuron to create post synaptic inhibition on the antagonist muscle |
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Term
what is an example of disfacilitation |
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Definition
in the direct pathway in the basal ganglia, the caudate and putamen inhibit the globus pallidus internal segment to keep it from inhibiting the thalamus |
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Term
what is presynaptic inhibition/axo-axonal synapse? |
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Definition
Neuron A synapses on Neuron B near Neuron B's terminal ending. This partially depolarizes the terminal end of Neuron B, relasing some of Neuron B's transmitter. The result is decreased available neurotransmitter, reducing the effect of a real action potential when it comes along |
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Term
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Definition
primary afferent depolarization |
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Term
what is primary afferent depolarization |
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Definition
the CNS sends excitatory connections down the psinal cord to the terminal ending to reduce the excitatory effects of the primary afferents |
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Term
are there any inhibitory afferents? |
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Definition
no. all primary afferents try to have a positive efefct that make semothing happen |
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Term
what are the primary afferents |
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Definition
touch, smell, hearing, pain, sensory |
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Term
what is the effect of presynaptic inhibition on the target cell? |
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Definition
decreased effect because there is not as much excitatory neurotransmitter |
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Term
what does MEPP stand for? |
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Definition
minature end plate potentials |
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Term
what is a miniature end plate potential? |
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Definition
A small miniature excitatory post synaptic potential in which the terminal ending is partially depolarized, resleasing small neurotransmitter packages |
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Term
describe an example of presynaptic inhibition |
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Definition
to reduce the incoming informaiton from primary afferents,t he CNS sends excitatory informatino down the psinal cord to the terminal ending to create miniature end plate potentials at the posts ynaptic membrane, reducing the available neurotransmitter and therefore reducing the effect of an action potential. |
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Term
what is surround or recurrent inhibhition? |
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Definition
when a recurrent collateral synapses with a nearby inhibitory neuron to reduce its activity and to acceentuate an excited area around an inhibitory area to sharpen contrast |
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Term
what is the purpose of surround or recurrent inhibition? |
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Definition
to sharpen tuning for finer localization by accentuating the excited area |
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Term
where is surround inhibition important? |
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Definition
retina, sensory cortex for 2 point discrimination |
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