Definitions of Addiction

Vulnerability to Addiction

A wide range of factors may predispose individuals to addiction, many of which provide insights into the etiology of the disorder. These include comorbidity with other psychiatric disorders, including anxiety, affective, personality, and psychotic disorders, and neurobehavioral traits, such as impulsivity, development (adolescence), psychosocial stress, and gender (see Table 1.3). The neurobiological differences in predisposing factors which are common to the neurobiological changes associated with addiction provide insights into the neuropathology associated with the development of addiction. Individual differences in temperament, social development, comorbidity, protective factors, and genetics are areas of intense research, and a detailed discussion of these contributions to addiction is beyond the scope of this book. Each of these factors presumably interacts with the neurobiological processes discussed in this book. A reasonable assertion is that the initiation of drug abuse is more associated with social and environmental factors, whereas the progression to a substance use disorder (addiction) is more associated with neurobiological factors. Temperament and personality traits and some temperament clusters have been identified as vulnerability factors, including impulsivity, novelty- and sensation-seeking, conduct disorder, and negative affect. From the perspective of comorbid psychiatric disorders, the strongest associations are found with mood disorders, anxiety disorders, antisocial personality disorders, and conduct disorders. The association between attention-deficit/hyperactivity disorder (ADHD) and drug abuse can be explained largely by the higher comorbidity with conduct disorder in these individuals. Independent of this association, little firm data indicate a higher risk caused by the pharmacological treatment of ADHD with stimulants, and no preference for stimulants over other drugs of abuse has been noted. In fact, children with ADHD who are treated with psychostimulants are less likely to develop a substance use disorder.

BOX 1.2

When Heather Brooks entered high school in 1991, her guidance counselor pegged her as someone with high potential. In her first semester, she earned top grades, She participated in many extracurricular activities.

A student of classical piano, Heather filled her family’s suburban Chicago home with Chopin and Beethoven. During her freshman year, 14-year-old Heather made friends with some older kids, and her life took a sudden turn. One evening while she was with them in a neighborhood park, a tall, good-looking junior handed her a marijuana cigarette. “Take a drag,” he urged, “it’ll mellow you out.” At first Heather held off. She’d always disapproved of drugs. But Justin reassured her. “It’s not a drug,” he said, “it’s only pot.” Heather decided to give it a try. "Okay," she conceded, “just one puff.”

With instructions from her friends, she pulled the sweet-smelling smoke into her lungs and held it there until she thought she’d burst. Then came more puffs. As she blew out the wispy remnants of smoke, she felt dizzy – and euphoric. "Give me another drag,” she begged, tugging on Justin’s arm. After a few more drags on the joint, Heather felt a deepening glow of contentment. Time slowed to a crawl. Colors and sounds seemed more intense. “Wow!” she thought, “This stuff is fantastic!”.

Her high lasted four hours. Heather couldn’t wait for the next invitation from her new friends. Because she’d taken the big step and smoked a joint, she felt a strong bond with them. She was confident someone would bring more pot to share. She wasn’t disappointed. The next weekend, when Justin offered her a joint, Heather took it eagerly. “Why do adults get so bent cut of shape over a little pot?” she wondered. All she knew was that the more she smoked, the more outrageously fabulous she felt. As Heather’s freshman year – and her use of marijuana – progressed, pot was no longer just a social drug. First thing in the morning, she smoked a joint to get herself out of bed. She smoked in a friend’s car on the way to school. Between classes she smoked in the bathroom. She was even stoned when she sang in a school choir concert.

To achieve a high, meanwhile, required ever increasing amounts of the substance. She graduated to using a bong, or water pipe, which concentrates the smoke inside a chamber so none is lost into the air. "The only thing wasted," a bong purveyor promised, “is you.” Heather didn’t worry that she needed more and more of the stuff. To her, this was a sign of prowess. “Look how much I can smoke and not get loaded,” she bragged. And she downplayed thoughts of addiction. Pot, her friends kept reminding her, wasn’t any more habit-forming than milk. She was sure she could quit any time. When Heather’s parents asked how school was going, she always flashed a big smile. “Everything’s fine,” she’d say. Because she’d always been such a good daughter, Frank and Diana Brooks had every reason to believe her. Gradually, though, Heather had become a highly accomplished liar. “I’ll be at Amy’s house after school,” she said one morning, looking her mother squarely in the eye. Instead, Heather drove with her friends to a dead-end dirt road where they smoked pot until it was time to go home for dinner.

On Friday nights, Heather came home promptly at her eleven o’clock curfew and said good-night to her parents. After the sliver of light under their door went out, she waited ten minutes, then tiptoed downstairs and slipped out the door to go party.

When Heather’s gang smoked pot, they also always drank – beer or tumblers of vodka and cranberry juice. The alcohol made Heather feel more mellow than ever. It also amazed her how much she could drink without ever getting sick.

At school Heather’s absences began to mount and her grades took a nose dive. Yet for a while she continued to fool her parents. When report cards were mailed, she intercepted them at home and, with skillful use of correction fluid and a photocopying machine, turned Ds and Fs to As and Bs. She even added some nice comments: “Heather is a pleasure to have in class,” she wrote, imitating the handwriting of one of her teachers. By the end of Heather’s freshman year, her grade-point average had plummeted from 4.0 to 1.2, and she’d tallied up a staggering 39 absences. Meanwhile, Heather dropped many of her extracurricular activities. When her parents asked why, she said she just needed some “space.” Diana and Frank Brooks pinned this on normal teenage turmoil.

By now, Heather no longer cared about anyone or anything – except her next high. Her drive and motivation were gone, replaced by total apathy. Drugs had become her life. She couldn’t stop. In her journal she wrote: “Pot is a motionless sea of destruction. I’m drowning.” Indeed, always in excellent health, Heather now felt sick much of the time. Her hands and feet were constantly cold. She woke up coughing and pushed her face deep into her pillow so her parents wouldn’t hear her. She also noticed that her menstrual cycle had become irregular. Heather’s parents saw the changes in their daughter. But their questions turned up nothing, and they were worried. By her sophomore year, Heather knew all the tricks. To hide the smell of pot in her room, she stuffed an empty paper-towel roll with a sheet of fabric softener and exhaled into the tube. She carried eye drops to clear up bloodshot eyes. Before heading home, she gargled with mouthwash or chewed cinnamon-flavored gum. Often she brought a clean shirt to a party and left the smoke saturated one behind.

As Heather’s pot intake increased, she wanted even more. Encouraged by her friends, she experimented with a variety of mind-altering substances: LSD, mescaline, crack, codeine, cocaine and amphetamines. Through it all, however, marijuana remained her “drug of choice.” It was what she started out with, and what she ended up with.

One warm night toward the end of Heather’s sophomore year, she attended what had become a typical party for her: the host’s parents were away, and there was plenty of liquor along with a variety of drugs. Heather wasn’t supposed to be there. Through conferences with her guidance counselor, her parents had found out about her doctored grades and her frequent absences. They now suspected alcohol or drugs and grounded her. But that evening her parents had gone out. Heather figured she could slip out and be back before they returned.

Around 10 p.m., she hopped in the back seat of a car with four others for a ride home. Ryan, the driver, was both drunk and stoned. As he stomped on the accelerator on a straight stretch of highway, Heather saw the speedometer pass 100 m.p.h. Moments later, the car slammed into a guardrail, rolled down an embankment and came to rest on its roof. Miraculously, everyone survived. Ryan’s face was jammed onto the steering-wheel horn, which blared loudly. Others bled from their faces and dangled broken limbs. Numbed by alcohol, marijuana and cocaine, Heather was oblivious of her own injuries as she helped one of her friends from the tangled wreck. Heather had suffered severe injuries to her back and neck, and would need a year of physical therapy. “I didn’t know Ryan had been drinking,” Heather lied to her parents. They wanted desperately to believe her. Relieved that she was alive, they forgave her “just this once” for sneaking out. From then on, they warned, they were tightening their watch. But while she recuperated at home, Heather smoked pot secretly. Heather had been dating Charlie Evans. He was handsome, athletic and popular with the girls. He was also heavily into marijuana and cocaine. One evening three months after her accident, Charlie appeared at the front door with an eight-ball of cocaine (about an eighth of an ounce). Her parents were out to dinner. Soon Heather and Charlie were sniffing the white powder through straws. After several lines, her heart began to race, something that had never happened before. She smoked a few joints to “mellow out,” but instead she became more jumpy. Looking down, she saw her shirt move with the heavy pounding of her heart. Terrified, she told Charlie to call for help. He dialed 911. “Send someone quick,” he yelled. He didn’t wait around. “I’ve got to split before the cops get here,” he said, going out the back door. En route to the hospital, Heather’s heart rate soared to 196 beats a minute. “Talk to us,” a paramedic urged, “we don’t want to lose you.” Finding Heather in intensive care and learning that she’d overdosed on cocaine, Diana Brooks broke into anguished cries. This was the wake-up call that Heather had long needed – and her parents too. “You’ve hit rock bottom,” Frank told his daughter later, “we’re still your best friends – but we’re going to be watching you every minute.” Each morning, Frank Brooks waited to leave for work until Heather was on her bus. When she returned, a parent was waiting for her. No more rides with friends. No more parties.

That summer, her parents took her to a La Jolla, Calif., beach house to get her away from her “friends.” For four full weeks, Heather was shaky, nervous and sweaty as her body adjusted to a healthier lifestyle. She had so much difficulty adapting to any kind of schedule that she wasn’t sure when to eat or sleep. Slowly, however, her numbed brain began to function. Frequently, she thought about the time she spent in the hospital: “I almost died, and none of my friends even came to visit.” Returning to Chicago, Heather was as determined to turn her life around as she once seemed determined to destroy it. She doubled up on courses she had failed as a sophomore. The sounds of her piano once again filled the Brooks home.

As a senior, Heather traveled to Europe with the school choir. As she stood in an ancient cathedral, her soprano voice joining the others, she recalled the concert when she’d shown up stoned.

“Just three years ago,” she thought, “What a different person I am now.” From: Ola P, D’Aulaire E. Here’s what marijuana can do inside a teenager’s body: “But It’s Only Pot.” Reader’sDigest, 1997, Jan:83–89.

BOX 1.3

We head north to the cabin. Along the way I learn that my parents, who live in Tokyo, have been in the States for the last two weeks on business. At four a.m. they received a call from a friend of mine who was with me at a hospital and had tracked them down in a hotel in Michigan. He told them that I had fallen face first down a fire escape and that he thought they should find me some help. He didn’t know what I was on, but he knew there was a lot of it and he knew it was bad. They had driven to Chicago during the night.

We drive on and after a few hard silent minutes we arrive. We get out of the car and we go into the house and I take a shower because I need it. When I get out there are some fresh clothes sitting on my bed. I put them on and I go to my parents’ room. They are up drinking coffee and talking but when I come in they stop.


Mom starts crying again and she looks away. Dad looks at me.

“Feeling better?”


“You should get some sleep.”

“I’m gonna.”


I look at my Mom. She can’t look back. I breathe.

“I just.”

I look away.

“I just, you know.”

I look away. I can’t look at them.

“I just wanted to say thanks for picking me up.”

Dad smiles. He takes my Mother by the hand and they stand and they come over to me and they give me a hug. I don’t like it when they touch me so I pull away.

“Good night.”

“Good night, James. We love you.”

I turn and I leave their room and I close their door and I go to the kitchen. I look through the cabinets and I find an unopened half-gallon bottle of whiskey. The first sip brings my stomach back up, but after that it’s all right. I go to my room and I drink and I smoke some cigarettes and I think about her. I drink and I smoke and I think about her and at a certain point blackness comes and my memory fails me.

Back in the car with a headache and bad breath. We’re heading north and west to Minnesota. My Father made some calls and got me into a clinic and I don’t have any other options, so I agree to spend some time there and for now I’m fine with it. It’s getting colder.

I want to run or die or get fucked up. I want to he blind and dumb and have no heart. I want to crawl in a hole and never come out. I want to wipe my existence straight off the map. Straight off the fucking map. I take a deep breath.

We enter a small waiting room.

They’re gonna check you in now.

We stand and we move toward a small room where a man sits behind a desk with a computer. He meets us at the door.

“You ready to get started?”

I don’t smile.


He gets up and I get up and we walk down a hall. He talks and I don’t. “The doors are always open here, so if you want to leave, you can. Substance use is not allowed and if you’re caught using or possessing, you will be sent home. You are not allowed to say anything more than hello to any women aside from doctors, nurses, or staff members. If you violate this rule, you will be sent home. There are other rules, but those are the only ones you need to know right now.”

We walk through a door into the medical wing. There are small rooms and doctors and nurses and a pharmacy. The cabinets have large steel locks. He shows me to a room. It has a bed and a desk and a chair and a closet and a window. Everything is white.

He stands at the door and I sit on the bed.

“A nurse will be here in a few minutes to talk with you.”


“You feel okay?”

“No, I feel like shit.”

“It’ll get better.”


“‘Trust me.”


The man leaves and he shuts the door and I’m alone. My feet bounce, I touch my face, I run my tongue along my gums. I’m cold and getting colder. I hear someone scream.

The door opens and a nurse walks into the room. She wears white, all white, and she is carrying a clipboard. She sits in the chair by the desk.

“Hi James.”


“I need to ask you some questions.”

“All right.”

“I also need to check your blood pressure and your pulse.”

“All right.”

“What type of substances do you normally use?”


“Every day?”


“What time do you start drinking?”

“When I wake up.”

She marks it down.

“How much per day?”

“As much as I can.”

“How much is that?”

“Enough to make myself look like I do.”

She looks at me. She marks it down.

“Do you use anything else?”


“How often?”

“‘Every day.”

She marks it down.

“How much?”

“As much as I can.”

She marks it down.

“In what form?”

“Lately crack, but over the years, in every form that it exists.”

She marks it down.

“Anything else.”

“Pills, acid, mushrooms, meth, PCP and glue.”

Marks it down.

“How often?”

“When I have it.”

“How often?”

“A few times a week.”

Marks it down.

She moves forward and draws out a stethoscope.

“How are you feeling.”


“In what way?”

“In every way.”

She reaches for my shirt.

“Do you mind?”


She lifts my shirt and she puts the stethoscope to my chest. She listens.

“Breathe deeply.”

She listens.

“Good. Do it again.”

She lowers my shirt and she pulls away and she marks it down.

“Thank you.”

I smile.

“Are you cold?”


She has a blood pressure gauge.


“Do you feel nauseous?”


She straps it on my arm and it hurts.

“When was the last time you used?”

She pumps it up.

“A little while ago.”

“What and how much?”

“I drank a bottle of vodka.”

“How does that compare to your normal daily dosage?”

“It doesn’t.”

She watches the gauge and the dials move and she marks it down and she removes the gauge.

“I’m gonna leave for a little while, but I’ll be back.”

I stare at the wall.

“We need to monitor you carefully and we will probably need to give you some detoxification drugs.”

I see a shadow and I think it moves but I’m not sure.

“You’re fine right now, but I think you’ll start to feel some things.”

I see another one. I hate it.

“If you need me, just call.”

I hate it.

She stands up and she smiles and she puts the chair back and she leaves. I take off my shoes and I lie under the blankets and I close my eyes and I fall asleep.

I wake and I start to shiver and I curl up and I clench my fists. Sweat runs down my chest, my arms, the backs of my legs. It stings my face.

I sit up and I hear someone moan. I see a bug in the corner, but I know it’s not there. The walls close in and expand. They close in and expand and I can hear them. I cover my ears but it’s not enough.

I stand. I look around me. I don’t know anything. Where I am, why, what happened, how to escape. My name, my life.

I curl up on the floor and I am crushed by images and sounds. Things I have never seen or heard or even knew existed. They come from the ceiling, the door, the window, the desk, the chair, the bed, the closet. They’re coming from the fucking closet. Dark shadows and bright lights and flashes of blue and yellow and red as deep as the red of my blood. They move toward me and they scream at me and I don’t know what they are but I know they’re helping the bugs. They’re screaming at me.

I start shaking – shaking and shaking and shaking. My entire body is shaking and my heart is racing and I can see it pounding through my chest and I’m sweating and it stings. The bugs crawl onto my skin, and they start biting me and I try to kill them. I claw at my skin, tear at my hair, start biting myself. I don’t have any teeth and I’m biting myself and there are shadows and bright lights and flashes and screams and bugs, bugs, bugs. I am lost. I am completely fucking lost.

I scream.

I piss on myself.

I shit my pants.

The nurse returns and she calls for help and men in white come in and they put me on the bed and they hold me there. I try to kill the bugs but I can’t move so they live. In me. On me. I feel the stethoscope and the gauge and they stick a needle in my arm and they hold me down.

I am blinded by blackness.

I am gone.

Excerpt from A Million Little Pieces by James Frey, © 2003 by James Frey. Used by permission of Doubleday, an imprint of the Knopf Doubleday Publishing Group, a division of Random House LLC. All Rights Reserved.


12-Month Prevalence of Comorbid Disorders among Respondents with Nicotine Dependence, Alcohol Dependence, or any Substance Use Disorder

Grant BF, Hasin DS, Chou SP, Stinson FS, Dawson DA, Nicotine dependence and psychiatric disorders in the United States: results from the National Epidemiologic Survey on Alcohol and Related Conditions, Archives of General Psychiatry, 2004, (61), 1107–1115.

Grant BF, Stinson FS, Dawson DA, Chou SP, Dufour MC, Compton W, Pickering RP, Kaplan K, Prevalence and co-occurrence of substance use disorders and independent mood and anxiety disorders: results from the National Epidemiologic Survey on Alcohol and Related Conditions, Archives of General Psychiatry, 2004, (61), 807–816.

Grant BF, Stinson FS, Dawson DA, Chou SP, Ruan WJ, Pickering RP Co-occurrence of 12-month alcohol and drug use disorders and personality disorders in the United States: results from the National Epidemiologic Survey on Alcohol and Related Conditions, Archives of General Psychiatry, 2004, (61), 361–368.

Developmental factors are important components of vulnerability, with strong evidence that adolescent exposure to alcohol, tobacco, and drugs of abuse leads to a significantly higher likelihood of drug dependence and drug-related problems in adulthood. Individuals who experience their first intoxication at 16 or younger are more likely to drink and drive, ride with an intoxicated driver, be seriously injured when drinking, become heavy drinkers, and develop substance dependence on alcohol (Figure 1.5). Similarly, people who smoke their first cigarette at 14–16 years of age are 1.6 times more likely to become dependent than people who begin to smoke when they are older. Others have argued that regular smoking during adolescence raises the risk of adult smoking by a factor of 16 compared with nonsmoking during adolescence. The age at which smoking begins influences the total years of smoking, the number of cigarettes smoked, and the likelihood of quitting (Figure 1.6). When the prevalence of lifetime illicit or nonmedical drug use and dependence was estimated for each year of onset of drug use from ages ≤ 13 and ≥ 21, the early onset of drug use was a significant predictor of the subsequent development of drug abuse (Figure 1.7). Overall, the lifetime prevalence of substance dependence (measured by the DSM-IV criteria) among people who began using drugs under the age of 14 was 34%. This percentage dropped to 14% for those who began using at age 21 or older.

The adolescent period is associated with specific stages and pathways of drug involvement. Initiation usually begins with legal drugs (alcohol and tobacco). Involvement with illicit drugs occurs later in the developmental sequence, and marijuana is often the bridge between licit and illicit drugs. However, although this sequence is common, it does not represent an inevitable progression. Only a very small percentage of young people progress from one stage to the next and on to late-stage illicit drug use or dependence (for further reading, see Kandel, 1975).

FIGURE 1.5 Representative college alcohol survey. (A) Alcohol dependence according to age first intoxicated. (B) Past 30 days of heavy episodic drinking according to age first intoxicated. After controlling for personal and demographic characteristics and respondent age, the odds of meeting alcohol dependence criteria were 3.1 times greater for those who were first drunk at or prior to age 12 compared with drinkers who were first drunk at age 19 or older. The relationship between early onset of being drunk and heavy episodic drinking in college persisted even after further controlling for alcohol dependence. Respondents who were first drunk at or prior to age 12 were 2.1 times to report recent heavy episodic drinking than college drinkers who were first drunk at age 19 or older. [Taken with permission from Hingson R, Heeren T, Zakocs R, Winter M, Wechsler H. Age of first intoxication, heavy drinking, driving after drinking and risk of unintentional injury among US college students. Journal of Studies on Alcohol, 2003, (64), 23–31.]

FIGURE 1.6 Percentage of adolescent regular smokers who became adult regular smokers as a function of grade of smoking initiation. The subjects consisted of all consenting 6th to 12th graders in a Midwestern county school system in the United States who were present in school on the day of testing. All 6th to 12th grade classrooms (excluding special education) were surveyed annually between 1980 and 1983. A potential pool of 5,799 individuals had been assessed at least once during adolescence between 1980 and 1983. At the time of follow-up, 25 of these subjects were deceased, 175 refused participation, and 4,156 provided data (72%). The subjects were predominantly Caucasian (96%), equally divided by sex (49% male, 51% female), and an average of 21.8 years old. Of the respondents, 71% had never been married, and 26% were currently married; 58% had completed at least some college by the time of follow-up; 32% were still students; and 43% had a high school education. For nonstudents, occupational status ranged from 29% in factory, crafts, and labor occupations, to 39% in professional, technical, and managerial occupations. At follow-up, the overall rate of smoking at least weekly was 26.7%. [Taken with permission from Chassin L, Presson CC, Sherman SJ, Edwards DA. The natural history of cigarette smoking: predicting young-adult smoking outcomes from adolescent smoking patterns. Health Psychology, 1990, (9), 701–716.]

Genetic contributions to addiction can result from complex genetic differences that range from alleles that control drug metabolism to hypothesized genetic control over drug sensitivity and environmental influences. The classic approach to studying complex genetic traits is to examine co-occurrence or comorbidity in monozygotic vs. dizygotic twins who are reared together or apart or in family studies with biological relatives. Twin and adoption studies provide researchers with estimates of the extent to which genetics influence a given phenotype, termed heritability. Genetic factors may account for approximately 40% of the total variability of the phenotype (Table 1.4). In no case does heritability account for 100% of the variability, which argues strongly for gene–environment interactions, including the specific stages of the addiction cycle, developmental factors, and social factors.

FIGURE 1.7 Prevalence of lifetime drug dependence by age at first drug use. The prevalence of lifetime dependence decreased steeply with increasing age of onset of drug use. Overall, the prevalence of lifetime dependence among those who started using drugs under the age of 14 years was approximately 34%, dropping sharply to 15.1% for those who initiated use at age 17, to approximately 14% among those who initiated use at age 21 or older. [Taken with permission from Grant BF, Dawson DA. Age of onset of drug use and its association with DSM-IV drug abuse and dependence: results from the National Longitudinal Alcohol Epidemiologic Survey. Journal of Substance Abuse, 1998, (10), 163–173.]

Genetic factors can also convey protection against drug abuse. For example, certain Asian populations who lack one or more alleles for the acetaldehyde dehydrogenase gene show significantly less vulnerability to alcoholism. A similar genetic defect in metabolizing nicotine has been discovered, in which those who metabolize nicotine more quickly have higher smoking rates and may also have a higher vulnerability to dependence (for further reading, see Tyndale et al., 2001).


Heritability Estimates for Drug Dependence

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