Drug Use, Dependence and Addiction

Question 1

If a drug is ingested, what’s the most likely place of absorption?

Answer 1

Intestinal absorption

Question 2

If a drug is inhaled, what’s the most likely place of absorption?

Answer 2

Absorbed through capillaries in lung

Question 3

Why is intravenously injection of a psychoactive drug highly effective?

Answer 3

It goes into the veins and the drugs are delivered directly to the brain

Question 4

What is meant by drug tolerance?

Answer 4

• Drug tolerance is a shift if the dose-response curve.

- in tolerant individuals, the same dose has less effect

Question 5

What is the difference between metabolic and functional tolerance?

Answer 5

• Functional tolerance: the sites of action becomes less responsive
• metabolic tolerance: less of the drug gets to the site of action

Question 6

Explain why withdrawal symptoms tend to be the opposite of the initial effects of the drug

Answer 6

When a person is dependent on a drug, it means their nervous system has adapted to its presence and requires it for normal functioning. The sudden absence of the drug disrupts this new balance and causes the opposite symptoms

Question 7

How was contingent tolerance demonstrated experimentally?

Answer 7

Two groups of rats receive a series of alcohol injections and stimulation of the amygdala that causes convulsions. One group gets the alcohol before stimulation and the other group after. Alcohol has anti-convulsive effect so if it’s present at the time of the stimulation the level of convulsions will be lowered

Question 8

Explain what we learn from the experiment on hypothermic effect

Answer 8

Regular drug users who always administer in the same setting can become tolerant to the drug so they keep increasing their dosage. However if they administer such high dose in a novel environment they may experience drug overdose effects

Question 9

Why is addiction different from drug dependence?

Answer 9

With drug dependence you need it for normal functioning whereas with addition you constantly crave the drug and you can be addicted to anything such as sex and games

Question 10

What are the problems with physical dependence theories of addiction?

Answer 10

Can’t explain why addicts relapse long after detoxification, addictions develop to drugs that do not produce severe withdrawal symptoms

Question 11

Which systems involving which neurotransmitter was found to be at the heart of drug reward?

Answer 11

Self stimulation increases dopamine in the meso-cortico-limbus pathway