Neuron Anatomy Part 2

Question 1

Action Potential vs Synaptic Transmission

Answer 1

Action: occurs when a neuron sends information
down an axon. It is an explosion of electrical activity that is created by a depolarizing current as a result of some stimulus

Synaptic: the process by which communication between neurons occurs

Question 2

Neurotransmitters

Answer 2

• The ultimate units of action of the nervous system
• Chemical molecules that allow for neuron communication to take place
• These are tiny molecules that are released from the pre-synaptic membrane into the synaptic cleft and attach to the receptor molecules in the post- synaptic membrane

Question 3

Excitatory Neurotransmitter

Answer 3

• Increase the likelihood that a neuron will fire an action potential
• Increases activity

Question 4

Inhibitory Neurotransmitter

Answer 4

• Decrease the likelihood that a neuron will fire an action potential
• Decreases activity

Question 5

Glutamate

Answer 5

• PF: Excitatory Neurotransmitter
  *Behaviors: Widespread, aka memory, learning
• the main excitatory neurotransmitter in the nervous system

Question 6

GABA

Answer 6

*Gamma Aminobutyric Acid
* PF: Inhibitory Neurotransmitter
*Behaviors: Widespread, aka muscle tone

Question 7

Dopamine

Answer 7

• PF: Excitatory Neurotransmitter
  *Behaviors: motor, mood, reward

Question 8

Norepinephrine

Answer 8

• PF: Excitatory Neurotransmitter
  *Behaviors: mood, attention, sleep, pain

Question 9

Epinephrine

Answer 9

• PF: Excitatory and Inhibitory Neurotransmitter
  *Behaviors: Blood pressure, airway diameter

Question 10

Serotonin

Answer 10

• PF: Excitatory and Inhibitory Neurotransmitter
  *Behaviors: mood, arousal

Question 11

Acetylcholine

Answer 11

• Excitatory; muscle contraction (skeletal)
  *Inhibitory; muscle contraction (heart)

Question 12

Epilepsy

Answer 12

glutamate is abnormally concentrated in the brain which induces neurotoxicity in the form of hyperexcitability and seizures
* seizures can damage the area where the word is stored, as well as the communication lines that carry or transport the word
* it is generally assumed that because of the resulting hyperactivity in neurons during the condition, there is an imbalance wherein excitatory neurotransmission predominantly through glutamatergic signaling is increased and inhibitory neurotransmission predominantly through GABA-ergic signaling is decreased
*Pharmacological Treatment is targeted towards use of GABA to inhibit activity. the likelihood that a neuron will fire an action potential

Question 13

Synaptic Transmission

Answer 13

*the process by which communication between neurons occurs
*Two basic forms:
- Electrical: Relays information through electricity (e.g., axon potentials propagate through neuronal gap junctions)
- Chemical: Relays information through chemicals (e.g.,
neurotransmitters carried over synaptic cleft)
* Neurotransmitter chemicals are released from vesicles in the synaptic terminal and attach to the chemical receptor molecules on target (post-synaptic cell membrane)

Question 14

motor

Answer 14

producing movement; describes neurons that carry impulses away from the CNS

Question 15

synaptic plasticity

Answer 15

change that occurs at synapses, the junctions between neurons that allow them to communicate.

*controls how effectively two neurons communicate with each other.

*The strength of communication between two synapses can be likened to the volume of a conversation. When neurons talk, they do so at different volumes – some neurons whisper to each other while others shout.

Question 16

Short-term synaptic plasticity

Answer 16

changes in synaptic strength that occur on a sub-second timescale: a rapid up or down adjustment of the volume control that helps determine how important that connection is to the ongoing conversation, but which reverts to “normal” soon afterwards

Question 17

Long-term synaptic plasticity

Answer 17

lasts anywhere from minutes to hours, days, or years. Long-term plasticity is the dominant model for how the brain stores information—in other words, for how we create and remember new memories