Addiction Worksheet

Question 1

What is the equation for the twin pair probandwise concordance rate

Answer 1

(2C)/(2C+X)

Question 2

What does C represent for probandwise concordance rate

Answer 2

Concordant pair - matching

Question 3

What does D represent for probandwise concordance rate

Answer 3

Discordant pair - mismatch

Question 4

A probandwise concordance rate that is higher in MZ twins than DZ twins indicates…

Answer 4

Genetic influence

Question 5

A probandwise concordance rate that is higher in DZ twins than MZ twins indicates…

Answer 5

Environmental influence

Question 6

What were the results of the twin-pair concordance study on alcoholism

Answer 6

1. MZ had a higher rate than DZ indicating a genetic link
2. Males had a higher rate overall compared to females

Question 7

Describe the pathway of alcohol metabolism

Answer 7

Alcohol is metabolized into acetaldehyde with the enzyme alcohol dehydrogenase and then acetaldehyde is broken down to acetic acid via the enzyme acetaldehyde dehydrogenase

Question 8

If alcohol dehydrogenase works faster, what is the impact?

Answer 8

decrease blood alcohol levels and increased acetaldehyde
-adverse reaction to alcohol, unlikely to abuse

Question 9

If alcohol dehydrogenase works slower, what is the impact?

Answer 9

Increased blood alcohol levels and decreased acetaldehyde
-Feel alcohol effects more than normal

Question 10

If acetaldehyde dehydrogenase works faster, what is the impact

Answer 10

decreased acetaldehyde
-less toxic response, increased risk of becoming an alcoholic

Question 11

If acetaldehyde dehydrogenase works slower, what is the impact?

Answer 11

Same blood alcohol level and increased acetaldehyde
- increased toxic response

Question 12

What area of the brain does the reward pathway originate in

Answer 12

ventral tegmental area

Question 13

Where do the cells in the reward pathway extend from and where do they synapse and what is released

Answer 13

Extend form the medial forebrain bundle and synapse in the nucleus accumbens and release dopamine

Question 14

Rank the following in order of most dopamine released to least amount of dopamine released;
Cocaine, meth, nicotine, cannabis, psilocybin and chocolate

Answer 14

Meth, cocaine, nicotine, cannabis, chocolate, psilocybin

Question 15

What happens to the brain when an addict sees a drug cue?

Answer 15

increase activation of the anterior cingulate cortex representing the expectation of emotional pleasure

Question 16

What happens to the body when an addict sees a drug cue?

Answer 16

Physiological counter response to the drug

Question 17

What are the 4 Cs of addiction

Answer 17

Cravings
Loss of control in amount or frequency of use
Compulsion to use
Use despite consequences

Question 18

What is the mechanism behind compulsion to use as an addict?

Answer 18

• Use of drugs causes a reduction in dopamine receptors in the reward system
  -lower levels of basal pleasure cause addicts to compulsively use the drug to feel good

Question 19

What is the mechanism behind loss of control and use despite consequences?

Answer 19

• Reduced activation of the frontal lobe
  -frontal and prefrontal cortices are needed for rational thinking and empathy

Question 20

How does adolescents risk taking behavior differ from adults

Answer 20

Adolescents are more susceptible to risk taking behavior because of their under-developed frontal lobe

Question 21

What is the mechanism behind cravings

Answer 21

activation of the reward system in anticipation of the drug
-through conditioning we can learn to associate cues with the administration of a drug
-Cues activate ACC and cause cravings

Question 22

Does addiction run in families?

Answer 22

Yes
-children of addicts are at increased risk of becoming addicts themselves
-alcoholism is more likely to co-occur in MZ twins than DZ twins, suggesting a genetic link

Question 23

Can we predict abuse according to how an individual responds to drugs?

Answer 23

Yes
-Low responders to alcohol are more likely to become alcoholics than high responders
-This could explain individual differences in why some children of alcoholics become alcoholics themselves whereas others do not

Question 24

How do genetics influence susceptibility to addiction?

Answer 24

• The ALDH2 gene codes for low vs high responders
• ALDH22/2 genotype is protective of alcohol abuse by inducing high responder phenotype

Question 25

Affects of weed

Answer 25

Bad for mental health
-THC is addictive
-elevates dopamine to supernatural levels
-chronic use blunts the release of dopamine to naturally rewarding stimuli
-causing drug dependency
-cannabis use is associated with schizophrenia psychosis

Question 26

Affects of magic mushrooms

Answer 26

-mimics serotonin to enhance mood
-minimal effect on dopamine
-promising therapy for drug-resistant depression