The Brain: Understanding Neurobiology Through the Study of Addiction by National Institute of Health. - HTML preview

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with a lethal outcome, such as by suppressing respiration. If you want

to modify the game to add this scenario, insert the jokers into each

pile of choice cards and have the students play the game a fourth

time. If a student draws a joker, the game is over for that student.

If you decide to do this optional modification to the game, make sure

that students understand that the joker does not indicate addiction.

The joker would, perhaps, represent a batch of drugs that contain a

lethal contami nant that would cause some body organ to fail and, thus,

cause the person using them to die. Another person, for example, takes

a large enough dose of opioids to completely inhibit the neurons in

the brain that control respira tion; those neurons no longer stimulate

the lungs to contract, causing death. Sometimes a drug can produce a

fatal response for unknown reasons; it could be due to a mutation in a

gene that reduces the body’s ability to metabolize a drug, leading to an

increased, possibly toxic, level of the drug in the body.

Activity 4: Environmental, Behavioral, and Social

Influences on Drug Abuse and Addiction

Note to teachers: This activity, as described in the following steps,

is designed as a class discussion. An alternative approach is to have

individual students write their answers to the questions and then

discuss the questions as a class.

Content Standard C:

1. Display a transparency of Master 4.5, Who Is Addicted? , showing only An individual’s mood and

the top section (to the first horizontal line). Ask students to answer

behavior may be modified

the question.

by substances.

Content Standard F:

Students may respond differently to the question about who is addicted

Personal choice concern ing

to morphine. At this stage, any answer is acceptable if the student can

fitness and health involves

explain the reasoning underlying his or her answer. Some students

will say that Chris is addicted because of the higher dose of morphine

multiple factors.

being taken over a longer period of time. Some students will say Pat

because this could be a larger dose than what Chris is taking (if Chris

is at 50 mg per day). Stu dents could also believe that both individuals

are addicted because of their continued drug abuse. Conversely,

students could respond that possibly neither one is addicted and more

information is needed before a judgment could be made.

2. Reveal the next section on Master 4.5 (to the next horizontal line).

Again have students answer the question and discuss the responses.

Students may respond in a variety of ways. Answers could involve

aspects of genetics, dose, or even random chance.

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Student Lesson 4

The Brain: Understanding Neurobiology Through the Study of Addiction

3. Reveal the remaining section of Master 4.5 and have students read the case studies.

4. Discuss the cases with the class. Use the following questions to

guide the discussion.

• Why did these two individuals begin taking morphine and

then con tinue to take morphine?

Pat began abusing morphine basically for social reasons. Chris began

tak ing morphine for medical reasons.

• What are the differences in how Chris and Pat take morphine?

Pat takes an injection of morphine one time each day. Chris also

receives morphine through injection, but he receives a dose many

times each day.

• How may these differences have influenced whether

addiction develops?

Although Chris receives a higher total dose of morphine during a day,

each single injection is a smaller dose. The smaller single dose does not

lead to the same high that results from a larger dose. Perhaps the fact

that Chris does not feel the euphoria when he receives the morphine

is important in keeping him from being addicted. (It is acceptable for

students to propose answers here even if they cannot be sure.)

• Is a larger dose of a drug the only factor to consider when

thinking about the causes of drug addiction? Explain your

answer based on the case studies.

No, because Chris took a larger dose and did not become addicted.

• Is the length of time that someone has been taking drugs

enough to determine whether addiction will develop?

Explain your answer based on the case studies.

No, because Chris took morphine for a longer period of time and did

not become addicted while Pat took morphine for a shorter period of

time and did become addicted.

• What factors other than the amount (dose) of the drug taken

and the period of time for which the drug is taken may

contribute to addiction?

The expectation of feeling a rush may be a factor. A person getting

mor phine in a hospital would not be taking morphine to get that

feeling. The context of drug (medication) use influences whether

a person becomes addicted. Pat’s use of drugs to escape problems

contributed to the develop ment of drug addiction.

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The cases should reveal to the students that a high dose of a drug is not

enough to cause addiction. The behaviors and motivations for taking

drugs are important factors in the development of addiction. The addicted

street person was using drugs with the expectation of a rush, or high,

and trying to escape life. The patient was taking drugs without the

expectation of a high. The patient experiencing pain uses drugs in order

to function normally. Sci entists do not completely understand why pain

patients do not become addicted after drug use, but the statistics clearly

show that these individu als are at very low risk of becoming addicted.

You may also want to discuss the case of Vietnam veterans with

students. For many years, the media portrayed Vietnam veterans as

hopelessly drug-addicted individuals. Although drug addiction was a

problem for some veterans while in Vietnam, the vast majority of those

veterans have had no problems with drug addiction since returning to

the United States. They may have started using drugs (and subsequently

became addicted) to relieve the stress of combat, to rebel against society,

or even to relieve boredom, but once they were back in a “normal”

environment, they were able to function without drugs.

Activity 5: Long-Term Effects of Drug Abuse and Addiction

Having students view the minidocumentary on the long-term effects

of drugs on the brain is the strongly preferred approach for this activity.

Content Standard A:

If the Internet is not available, follow the procedure for the alternate

version of the activity (on page 114).

Scientists rely on technology to enhance the

gathering and manipula

For classes using the Web version of this activity.

tion of data.

1. Have students view the minidocumentary, LongTerm Effects of

Drugs on the Brain, online.

To view the minidocumentary, which takes about five minutes,

go to the supplement’s Web site. From the activities menu, select Lesson 4— Drug Abuse and Addiction.

Having students write

2. After viewing the minidocumentary, ask students to write brief

their answers to the

answers to the following questions.

questions encourages

them to organize their

• What was the most surprising thing you learned about the

effect of drugs?

thoughts and reflect on

• What makes this fact surprising to you?

what they have learned.

• On the basis of what you have learned through the rat experiment

Listening to students

analysis, the card game, and the minidocumentary, would you say

explain their view about

that drug addiction is a disease? Justify your answer.

drug addiction as a

disease will help you

Students should be encouraged to relate what they learned in Activities

1 through 4 to what they learned from the minidocumentary.

evaluate their

understanding.

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Student Lesson 4

The Brain: Understanding Neurobiology Through the Study of Addiction

3. After students have completed their answers to the questions,

discuss the questions as a class.

Drug addiction is a disease that causes physical and functional

changes in the brain. This is similar to other diseases in which

a part of the body does not function properly.

4. Encourage students to learn about how drugs affect other body

systems by doing library or Internet searches.

Because the focus of this unit is the brain, the curriculum supplement

does not address how drugs act on other parts of the body. However, a

great deal of additional information is available online. See the section

Additional Resources for Teachers for some informative Web sites.

The following procedure is for classes using the print

version of the activity.

1. Give each student a copy of Master 4.6. Instruct students to read the handout LongTerm Effects of Drugs on the Brain and answer the

questions.

After students finish reading and answering the questions, discuss the

responses as a class.

Sample Answers to Questions on Master 4.6

Question 1. What are some of the ways that drugs cause longterm

changes in the brain?

The continued use of drugs may cause the brain to become resistant

to the effects of the drug (tolerance). Some drugs, such as alcohol,

methampheta mine, and MDMA, are neurotoxic; that is, they can

damage or kill brain cells. Cocaine and amphetamine can cause the

activity level of the brain to decrease for a long period of time after

drug use is stopped.

Question 2. How does the brain adapt to the presence of drugs?

The brain adapts to the presence of drugs through various alterations

in cellular, molecular, and genetic processes that affect its function.

The decrease in the number of dopamine receptors in the reward areas

is one example of a brain adaptation. Changes in the brain can lead

to the development of tolerance—a person needing more of a drug to

achieve the desired effect—and to cravings for the drug when drug

use has stopped.

114

Question 3. How may the abuse of drugs relate to the plasticity

of the brain?

Plasticity means that the brain can modify connections (synapses)

in response to experiences. Drugs that damage or kill neurons can

decrease the plasticity of the brain because neurons are not present

to form new connections and because existing connections are lost.

Drugs also hijack the learning and memory systems of the brain

so that cues (people, places, or things) that are associated with the

drug experience become powerful motivators of craving and drug

use. In fact, addiction is sometimes described as a disease of

learning and memory.

Question 4. What are some problems that scientists have when they

inves tigate the effects of drugs on the brain?

Scientists have difficulty investigating the effects of drugs on the

brain because many people who abuse drugs abuse more than one

drug. Scientists must understand how each drug affects the brain and

body because drugs taken in combination may have different effects.

Also, many people who abuse drugs have other medical conditions

that make it difficult for scientists to determine what effects are due

to the drug and what effects are due to those conditions. Scientists

also don’t know what someone’s brain was like before they used drugs.

This makes it hard to determine whether drug use caused the changes

or a vulnerability existed before drugs were used that made someone

susceptible to addiction.

2. If students want to learn more about how drugs affect other parts

of the body, encourage them to do library or Internet searches for

additional information.

Because this unit focuses on the brain, it does not address how drugs

act on other parts of the body. A great deal of information is available

online. See the section Additional Resources for Teachers (page 143) for

some informative Web sites.

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Student Lesson 4

The Brain: Understanding Neurobiology Through the Study of Addiction

Lesson 4 Organizer: WEB VErSION

What the Teacher Does

Procedure

reference

Activity 1: How Does Drug Abuse Begin?

Ask the class, “What is a drug?” Write responses on the board or a

Page 99

transparency. Allow differing views to be discussed.

Step 1

Write the following definitions for drug and medication on the

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board or transparency. Inform students that, for this discussion,

Step 2

you will use the terms according to these definitions.

• A medication is a drug that is used to treat an illness or disease

according to established medical guidelines.

• A drug is a chemical compound or substance that can alter the

structure and function of the body. Psychoactive drugs affect

the function of the brain, and some of these may be illegal to

use and possess.

Ask students to list examples of both medications and drugs.

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Step 3

Continue the class discussion by asking, “Why do people start

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abusing drugs?” Accept reasonable answers.

Step 4

Activity 2: Drug Abuse Is Voluntary; Addiction Is Compulsive

Organize students into groups of four. Explain how the rats in

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the experiment were in cages that had two levers. Depending on

Step 1

which lever the rat pressed, it receives a food reward or either an

injection or electrical stimulus.

Give each student a copy of Masters 4.1 and 4.2. Instruct groups to Page 101

choose one rat’s data to graph.

Step 2

Give each student a copy of Master 4.3. Ask groups to compare the

Page 101

graphs and discuss the similarities and differences among the rats’

Step 3

responses. Instruct students to answer the questions on Master 4.3.

Have a class discussion about the questions.

Pages 101–104

Step 4

Ask students to consider the question, Why do humans continue to

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abuse drugs?

Step 5

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What the Teacher Does

Procedure

reference

Write the definition of addiction on the board or overhead transparency.

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• Addiction is a chronic, relapsing brain disease characterized

Step 6

by compulsive drug-taking despite adverse health, social, or

legal consequences.

Ask students to consider whether Rat A (continued cocaine use)

Pages 104–105

and Rat C (continued stimulation of reward pathway) experienced

Step 7

any adverse effects. What adverse effects do drug-addicted

humans experience?

Prompt students to consider the distinction between abuse and

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addiction in humans by asking the following questions.

Step 8

• When does abuse become addiction?

• What causes abuse to become addiction?

• Does the change from abuse to addiction occur at the same level

(amount of drug taken, duration of drug abuse) of drug abuse

for different individuals?

Activity 3: When Does Abuse Become Addiction?

Divide the class into groups of three students. Give each group a

Page 105

deck of cards that have been divided into two piles. Tell the students

Step 1

that the small pile contains the face cards and the larger pile has the

aces and number cards.

Display a transparency of Master 4.4. Have students play through

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the game. Each student should play individually, but the group

Step 2

members will share the deck of cards.

As a class, discuss the game and the results. Guide the discussion

Pages 106–109

with the following questions.

Step 3

• How many choice cards did each person pick?

• How many people equaled or went over the value of the

switch card?

• How does this game relate to drug abuse and drug addiction?

• What does the transition, or switch, card mean in regard to

drug addiction?

• Is everyone’s transition, or switch, level the same?

• What does the risk card mean?

• Is everyone’s risk card the same?

• Why is the risk card face down?

• What factors influence a person’s risk of becoming addicted to drugs?

• What do the choice cards represent?

• If a total score that equals or goes over the switch value indicates

addiction, did anyone become addicted to drugs with the first drug

use?

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Student Lesson 4

The Brain: Understanding Neuobiology Through the Study of Addition

What the Teacher Does

Procedure

reference

Have students play the game again now that they can relate it to

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the issues of drug abuse and drug addiction.

Step 4

Ask students if they played the game any differently this time. Did

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they make different choices?

Step 5

Discuss the idea of the switch card. Does anyone really know at

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what point in drug abuse the brain changes and the person who

Step 6

is abusing drugs the abuser becomes an addict? How could you

modify the card game to account for this?

Have the students play the game again, but leave the switch card

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face down this time.

Step 7

Continue the discussion of the game and its relationship to drug

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abuse and addiction. Ask students to summarize the main points

Step 8

that the game conveys:

• Drug abuse involves choice.

• The point at which a person’s brain is changed and drug abuse

becomes addiction is different and unknown for each individual.

• Everyone has risk factors.

• A person does not become addicted to drugs after one episode of abuse.

To model the fact that one episode of drug abuse can result in

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lethal consequences (which is different from addiction), insert the

Step 9

jokers into the pile of choice cards. Have the students play the game

(optional)

again. If a student draws a joker, the game is over for that student.

Activity 4: Environmental, Behavioral, and Social Influences on

Drug Abuse and Addiction

Display the top section of a transparency of Master 4.5. Ask

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students to answer the question.

Step 1

Reveal the next section of Master 4.5. Again have students answer

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the question and discuss the responses.

Step 2

Reveal the remaining section of Master 4.5 and have students read

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the case studies.

Step 3

118

What the Teacher Does

Procedure

reference

Discuss the cases with the class using the following questions to

Pages 112–113

guide the discussion.

Step 4

• Why did these two individuals begin taking morphine and

then continue to take morphine?

• What are the differences in how Chris and Pat take morphine?

• How may these differences have influenced whether

addiction develops?

• Is a larger dose of a drug the only factor to consider when

thinking about the causes of drug addiction?

• Is the length of time that someone has been taking drugs

enough to determine if addiction will develop?

• What factors other than the amount (dose) of the drug taken

and the period of time for which the drug is taken may

contribute to addiction?

Activity 5: Long-Term Effects of Drug Abuse and Addiction

Ask the students to watch the minidocumentary online. From the

Page 113

activities menu, select Lesson 4— Drug Abuse and Addiction.

Step 1

Ask students to write answers to the following questions before

Pages 113–114

discussing the questions as a class.

Steps 2–3

• What was the most surprising thing you learned about the

effects of drugs?

• What makes this fact surprising to you?

• On the basis of what you have learned through analyzing the rat

experiment, the card game, and the minidocumentary, would

you say that addiction is a disease?

Encourage students to learn about how drugs affect other body