Brain and behaviour: Neurotransmission

Question 1

Neurotransmission

Answer 1

Is the process by which signalling molecules called neurotransmitters are released by the axon terminal of a neuron, and bind and react with the receptors of the dendrites of another neuron (a short distance away)

Question 2

Action potential

Answer 2

The electrical impulse which travels along the neuron

Question 3

Explain the process of neurotransmission, what happens?

Answer 3

• When an action potential travels down an axon in a neuron, it releases neurotransmitters
• The neurotransmitters get released into the gap between the neurons (synaptic gap)
• After crossing the synapse the neurotransmitters fit into receptor sites, on the post-synaptic membrane
• Once the message is passed on the neurotransmitters are broken down by enzymes in the synaptic gap and are reabsorbed into the vesicles in the pre-synaptic neuron ready to be released again
• Process known as reuptake

Question 4

What are the different types of neurotransmitters?

Answer 4

• Acetylcholine
• Dopamine
• Norepinephrine
• Serotonin

Question 5

What is the role of Acetylcholine?

Answer 5

• Consolidation of memory in the hippocampus

Question 6

What is the role of Dopamine?

Answer 6

• Motivation (low levels are linked to addiction)

Question 7

What is the role of Norepinephrine?

Answer 7

• Arousal and alertness

Question 8

What is the role of Serotonin?

Answer 8

• Sleep, arousal levels and emotion

Question 9

What are excitatory neurotransmitters?

Answer 9

Increase the likelihood of a neuron firing by depolarising the neuron (Acetylcholine)

Question 10

What are inhibitory neurotransmitters?

Answer 10

Decrease the likelihood of a neuron firing by hyperpolarising the neuron (GABA)

Question 11

What are antagonists?