Neurotransmission

Question 1

Structure of a neuron

Answer 1

Question 2

Action potential

Answer 2

The electrical impulse that travels along the body of the neuron

Question 3

Process of neurotransmission (6)

Answer 3

1. Electrical impulses travel along body of neuron
2. Travel down axon of neuron
3. Releases neurotransmitters that are stored in the neuron’s terminal buttons
4. Neurotransmitters released into the gap between neurons - synapses
5. Neurotransmitters fit into receptor sites on pstsynaptic membrane (like lock and key)
6. Broken down by an enzyme or reabsorbed by the terminal buttons (reuptake)

Question 4

Neurotransmitters

Answer 4

Natural chemical messengers that transmit information from one neuron to another

Question 5

Excitatory neurotransmitters

Answer 5

Increase the likelihood of a neuron firing by depolarising the neuron (like acetylcholine)

Question 6

Inhibitory neurotransmitters

Answer 6

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

Question 7

Metabotropic neurotransmitters

Answer 7

Only indirectly affect neuron and are considered neither excitatory nor inhibitory (serotonin, dopamine, norepinephrine)

Question 8

Acetylcholine

Answer 8

Plays a role in the consolidation of memory in the hippocampus

Question 9

Dopamine

Answer 9

Controls brain’s reward and pleasure centers - key role in motivation
* low levels are linked to addictive behaviour

Question 10

Norepinephrine

Answer 10

Arousal and alertness

Question 11

Serotonin

Answer 11

Sleep, arousal levels and emotion

Question 12

Limitations of neurotransmission (4)

Answer 12

• research can only be done indirectly
  
  • over-reliance on fMRI technology means limitations of technique apply here
• many studies are on animals - lack of reliability and generalisability
• research on humans is correlational in nature - can’t establish cause and effect (bidirectional ambiguity)
• argument that neurotransmitters are the cause of behaviour is reductionist - oversimplification of human behaviour

Question 13

Strengths of neurotransmitters (3)

Answer 13

• they have led to successful treatments for certain behaviours (drugs developed for psychological disorders)
• experimental research that supports the role of them in behaviour
• can be replicated to establish reliability

Question 14

Agonist

Answer 14

Chemicals that mimic a neurotransmitter at the receptor site and, thus, strengthen its effects

Question 15

Antagonist

Answer 15

Drugs that block the receptor site and do not allow the neurotransmitter to do its job, so no action potential is sent down the neuron

Question 16

Endogenous agonist

Answer 16

Biological chemical that binds to a receptor site (already part of our nervous system)
* all neurotransmitters are agonists for receptor sites (acetylcholine is an antagonist for ACh receptor sites)

Question 17

Exogenous agonists

Answer 17

External drugs that attach to a receptor site for a neurotransmitter and excite the neuron
* nicotine for ACh