lecture 9

Question 1

neurotransmission in Somatic nervous system

Answer 1

cholinergic neuron: neuron that uses ACh as main NT

- excited skeletal muscles to contract through nACh

Question 2

nicotinic acetylcholine receptors

Answer 2

• ACh or nicotine binds allowing pore to open and permit ion flow thus depolarizing muscle fiber
• allows K and Na to flow simultaneously
• wants to produce enough graded potentials to sum

Question 3

neurotransmission in autonomic nervous system

Answer 3

like SNS, also dominated by acetylcholine
parasympathetic:
- ACh exits cranial nerve and synapses on Ach
ACh receptors on heart are inhibitory and excitatory on gut
sympathetic:
- ACh exits spinal cord and synapses on NE neuron NE receptors on heart are excitatory and NE on gut are inhibitory

Question 4

transmission in enteric NS

Answer 4

uses all 4 classes of NT, mainly serotonin and dopamine

Question 5

neurotransmission in central nervous system

Answer 5

4 activating systems: cholingergic, dopaminergic, noradenergic and serotonergic

Question 6

activating system

Answer 6

neural pathways that coordinate brain activity through 1 NT

Question 7

cholinergic

Answer 7

set resting potential and maintain neuron excitability

• normal waking behavior, attention and memory
• associated with alzheimers
  nucleus: pontine nucleus

Question 8

dopaminergic system

Answer 8

1. nigrostriatal: coordinates movement, associated w parkinsons
2. mesolimbic: response to enviornmental stimuli, reward, decision making and addicition associated w/ schizophrenia
   nucleus: substantia nigra

Question 9

noradrenergic system

Answer 9

roll in learning
maintains emotional tone, anxiety (amgydala)
associated with depression
nucleus: locus coeruleus

Question 10

serotonergic

Answer 10

wakefullness, learning, mood
associated w depression, schizophrenia, OCD
nucleus: raphe nuclei

Question 11

learning

Answer 11

relatively permanent change in behavior resulting from experience
- know it has occured by observing changes in behavior

Question 12

neuroplasticity

Answer 12

the ability of the brain to change that enables learning and memory
- required for learning and memory

Question 13

hebbian synapse

Answer 13

cells that wire together fire together

• if 2 cells fire repeatedly close in time the connections will become more efficient
  ex. habituation and sensitization

Question 14

habituation

Answer 14

learning behavior in which response to a stimulus weakens with repeated presentations
ex. aplaysia habituates to waves

Question 15

neural basis of habituation

Answer 15

influx of Ca ion decreases - less NT is released - smaller depolarization of post synaptic
- takes place in axon terminal of sensory neuron

Question 16

sensitization

Answer 16

enhanced response to stimuli

ex. olympic runner jumps at the sound of a gun firing

Question 17

neural basis of sensitization

Answer 17

serotonin reduces K efflux creating a longer AP- more Ca enters- increased transmitter release- greater depolarization of post synap membrane
- - takes place in axon terminal of sensory neuron

Question 18

long term structural changes of habituation or sensitization

Answer 18

habituation: sensory neuron loses collaterals
sensitization: sensory neuron develops more collaterals