3.3 Synapses, Drugs, And Addictions

Question 0

A drug that blocks a neurotransmitter is an ____, where as a drug that mimics or increases the effects is an ____.

Answer 0

antagonist : agonist

Question 1

Drugs either ____ or ____ transmission at synapses.

Answer 1

facilitate or inhibit

Question 2

A ____ ____ is an agonist for some effects of the neurotransmitter and an antagonist for others or an agonist at some doses and an antagonist at others.

Answer 2

mixed agonist–antagonist

Question 3

A drug has an ____ for a receptor if it binds to it, like a key into a lock. Affinities vary from strong to weak.

Answer 3

affinity

Question 4

A drugs ____ is its tendency to activate the receptor. A drug that binds to a receptor but fails to stimulated it has a high affinity but low efficacy.

Answer 4

efficacy

Question 5

Reinforcing brain stimulation, reinforcing experiences, and self-administered drugs increase the activity of axons that release ____ or ____ in the nucleus accumbens.

Answer 5

dopamine or norepinephrine

Question 6

____ drugs increase excitement, alertness, and activity, while elevating mood and decreasing fatigue.

Answer 6

Stimulant

Question 7

Both ____ and ____ stimulate dopamine synapses in the nucleus accumbens and elsewhere by increasing the presence of dopamine in the presynaptic terminal.

Answer 7

amphetamine and cocaine

Question 8

Reuptake: the presynaptic terminal ordinarily reabsorbs released dopamine through a protein called the ____ ____. Amphetamine and cocaine inhibit the transporter, thus decreasing reuptake and prolonging the effect of released dopamine.

Answer 8

dopamine transporter

Question 9

Amphetamine has similar effects on the ____ and ____ transporters. Methamphetamine has effects similar to those of amphetamine, but stronger.

Answer 9

serotonin and norepinephrine

Question 10

Thus, stimulant drugs increase the ____ of dopamine in the synaptic cleft.

Answer 10

accumulation

Question 11

Excess dopamine in the synapses washes away faster than the presynaptic cell makes more to replace it. A few hours after taking a stimulant drug, the user has a deficit of the transmitters and enters a ____ ____, marked by reduced energy, reduced motivation, and mild depression.

Answer 11

withdrawal state

Question 12

Stimulant drugs produce varied behavioural effects. ___ doses enhance attention, and ___ doses of amphetamine are sometimes used as a treatment for attention deficit disorder. However, ___ doses of stimulant drugs impair attention and learning.

Answer 12

Low : Low : high

Question 13

By altering blood flow, cocaine also increases the risk of ____ and ____.

Answer 13

stroke and epilepsy

Question 14

____ (Ritalin), another stimulant drug, is also prescribed for people with attention deficit hyperactivity disorder. Methylphenidate and cocaine block the reuptake of dopamine in the same way at the same brain receptors.

Answer 14

Methylphenidate

Question 15

Nicotine, a compound present in tobacco, stimulates a family of acetylcholine receptors, conveniently known as ____ ____.

Answer 15

nicotinic receptors

Question 16

Nicotinic receptors are abundant on neurons that release dopamine in the ____ ____, so nicotine increases dopamine release there.

Answer 16

nucleus accumbens

Question 17

One consequence of repeated exposure to nicotine is that receptors in the nucleus accumbens become more ____ to nicotine. However they become less ____ to other kinds of reinforcement.

Answer 17

sensitive : responsive

Question 18

____ drugs are derived from, or chemically similar to those derived from, the opium poppy. Familiar opiates including morphine, heroine, and methadone.

Answer 18

Opiate

Question 19

Opiates relax people, ____ their attention to real-world problems, and ____ this sensitivity to pain.

Answer 19

decrease

Question 20

Investigators found that the brain produces a certain neuropeptides known as ____ – a concentration of endogenous morphines.

Answer 20

endorphins

Question 21

This discovery was important because indicated that ____ relieve pain by acting on receptors in the brain. This finding also paved the way for the discovery of other neuropeptides that regulate emotions and motivations.

Answer 21

opiates

Question 22

Endorphins indirectly activate ____ release. Endorphin synapses inhibit neurons that release GABA, a transmitter that inhibits the firing of ____ neurons. By inhibiting and inhibitor, the net effect is to increase ____ release.

Answer 22

dopamine

Question 23

Marijuana leaves contain chemical ____ (THC) and other cannabinoids (chemicals related to THC).

Answer 23

tetrahydrocannabinol

Question 24

Common psychological effects of marijuana include an intensification of ____ ____ and an illusion that time has ____ ____. Studies have reported impairments of memory and cognition.

Answer 24

sensory experience : slowed down

Question 25

Cannabinoid receptors are among the most ____ receptors in many areas of the mammalian brain.

Answer 25

abundant

Question 26

The chemicals in marijuana decrease both ____ and ____ messages from many neurons.

Answer 26

excitatory and inhibitory

Question 27

Cannabinoids relieve ____ by inhibiting serotonin type three synapses, which are known to be important for ____.

Answer 27

nausea

Question 28

Cannabinoid receptors are abundant in areas of the hypothalamus and hippocampus that influence ____, and stimulation of these receptors increases the rewarding value of a ____.

Answer 28

feeding : meal

Question 29

Drugs that distort perception are called ____ drugs.

Answer 29

hallucinogenic

Question 30

Many hallucinogenic drugs, such as ____ ____ ____ (LSD), chemical resemble serotonin.

Answer 30

lysergic acid diethylamide