Excitatory and Inhibitory Neurotransmitter

Question 1

What do excitatory neurotransmitter do?

Answer 1

Increase the likelihood that an excitatory signal is sent to the postsynaptic cell, which is then more likely to fire

Question 2

What do inhibitory neurotransmitters do?

Answer 2

• Decrease the likelihood of that neuron firing
• Generally responsible for calming the mind and body, inducing sleep and filtering out unnecessary excitatory signals

Question 3

Give examples of excitatory neurotransmitter

Answer 3

Acetylcholine (ACh) and noradrenaline

Question 4

Give examples of inhibitory neurotransmitter

Answer 4

Serotonin and GABA

Question 5

What is EPSP?

Answer 5

Excitatory neurotransmitters bind with a postsynaptic receptor causes an electrical change in the membrane of that cell, resulting in an excitatory post-synaptic potential (EPSP), meaning that the postsynaptic cell is more likely to fire

Question 6

What is IPSP?

Answer 6

Inhibitory neurotransmitters binding with a postsynaptic receptor results in an inhibitory postsynaptic potential (IPSP), making it less likely that the cell will fire

Question 7

How do we determine the likelihood of the cell firing?

Answer 7

• A nerve cell can receive both EPSPs and IPSPs at the same time.
• The likelihood of the cell firing is determined by adding up the excitatory and the inhibitory synaptic input
• The net results of this calculation (summation) determines whether or not the cell fires

Question 8

How can the strength of the EPSP be increased?

Answer 8

• In spatial summation, a large number of EPSPs are generated at many different synapses on the same postsynaptic neuron
• In temporal summation, a larger number of EPSPs are generated at the same synapse by a series of high-frequency action potentials on the presynaptic neuron