1.4 The Brain and Behaviour; Neurotransmission

Question 1

Action potential

Answer 1

The electrochemical impules that passes down the axon. Also known as spike, nerve impulse, or discharge. Action potential sweep like a wave along the axons to transfer information from one place to another in the nervous system

Question 2

Agonist

Answer 2

A chemical that binds to the receptor site of a post-synaptic neuron and increases the effect of the neurotansmitter.

Question 3

Antagonist

Answer 3

A chemical that binds to the receptor site of the neuron and decreases the neurotransmitter action at the postsynaptic neuron to counteract a neurotransmitter and so prevent a signal from being passed further. Drugs reducing dopamine for people diagnosed with schizophrenia are antagonist chemicals.

Question 4

Dopamine

Answer 4

A neurotransmitter that acts in the brain’s reward and pleasure areas to raise our mood. It is responsible for motivation towards rewards and is often involved in addictive behaviour. People with low dopamine are thought to be more likely to be easily addicted to substances like caffeine, nicotine, alcohol and some other drugs, which raise the dopamine levels in the brain, and thus increasing feelings of pleasure. Low levels are linked to Parkinson’s Disease

Question 5

Monoamines

Answer 5

A group of common and influential neurotransmitters (serotonin, dopamine, adrenaline, and noradrenaline)

Question 6

Inhibitory synapses

Answer 6

The actions of some synapses is to take the membral potention away from the action potential threshold.

Question 7

Excitatory synapse

Answer 7

Increase the likelihood that the neuron will fire an action potential. It is also when a drug attaches to a receptor site for a neuron and activates the neuron as if the neurotransmitter was sending a message

Question 8

MAO-A - monoamine oxidase

Answer 8

An enzyme that metabolizes (breaks down) monoamines, such as serotonin, norepinephrine, and dopamine.

Question 9

Neurotransmission

Answer 9

Process triggered by a neuron being stimulated either by environment or by chemical information from other cells. Traansmission occurs when one neuron (nerve cell) influences the activity of an anatomically neighbouring neuron. An electrical charge passes through the neuron, causing the terminal buttons to release neurotransmitters (substances that transfer information) into the synapse

Question 10

Neurotransmitters

Answer 10

Chemical substances that carry messges across the synaptic space to other neurons, muscles and glands

Question 11

Receptor agonist

Answer 11

A drug that binds to a recceptor and activates it

Question 12

Receptor antagonist

Answer 12

A drug that binds to a receptor and inhibits its action

Question 13

Serotonin

Answer 13

A neurotransmitter that works to regulate mood, appetite and sleep. Low levels of serotonin have been linked to clinical unipolar depression and high levels of aggression. High levels of serotonin have been linked to hallucinations.

Question 14

The Serotonin Hypothesis

Answer 14

Claims that major depression is an effect of low levels of serotonin

Question 15

SSRI (selective serotonin reuptake inhibitor)

Answer 15

A drug, such as fluoxetine (prozac), that prolongs the actions of synaptically released serotonin by preventing uptake; used to treat depression and obsessive-compulsive disorder

Question 16

Synapse

Answer 16

Extremely small gaps between adjacent neurons. A neuron communicates with another neuron by sending chemicals, transmitters, across the synaptic gap