ENDURING ISSUES IN STATES OF CONSCIOUSNESS
The mind-body relation is central to this entire chapter since we will be exploring ways in which psychological states can affect biological processes and, conversely, the ways in which biological changes can profoundly affect psychological experiences. In addition, we will discover that there are significant differences among people in their susceptibility to various altered states of consciousness (Diversity-Universality) and that the setting in which consciousness-altering substances are taken can greatly alter their effects (Person-Situation).
SLEEP
Human beings spend about one-third of their lives in the altered state of consciousness known as sleep: a natural state of rest characterized by a reduction in voluntary body movement and decreased awareness of the surroundings. No one who has tried to stay awake longer than 20 hours at a time could doubt the necessity of sleep. When people are deprived of sleep, they crave sleep just as strongly as they would food or water after a period of deprivation. Merely resting doesn't satisfy us.
All birds and mammals sleep; frogs, fish, and even insects go into "rest states" similar to sleep. Indeed, Drosophila fruit flies, a favorite subject for genetic studies because they reproduce rapidly, are remarkably like us: They are active during the day and somnolent at night; when deprived of sleep, they need long naps to recover. Caffeine keeps them awake, whereas antihistamines make them drowsy (Hendricks & Sehgal, 2004; Wu, Ho, Crocker, Yue, Koh, & Sehgal, 2009). How long organisms sleep, where, in what positions and the consequences of sleep deprivation vary from species to species (Kavanau, 2010; J. M. Siegel, 2008).
Nobody knows exactly why we need to sleep, although evidence has begun to accumulate that sleep plays an important restorative function, both physically and mentally. For instance, research has shown that getting adequate sleep boosts our immune response, making us less susceptible to disease (Faraut et al., 2010; Ingiosi, Opp, & Kreuger, 2013). Sleep also cleanses the body of chemical released when cells use energy to do their jobs (Tobin, 2007). One of those chemicals is adenosine, which builds up during the day and eventually signals the brain that is time to sleep (Thakkar, Winston, & McCarley, 2003). Caffeine works by temporarily blocking adenosine receptors in the brain. In contrast illness, which triggers infection, increases adenosine levels making us want to sleep more (Nadjar, Blutstein, Aubert, Laye, & Haydon, 2013). Sleep also contributes to cognitive functioning. For example, when people are presented with complex problems and are permitted to sleep prior to solving them, they are more likely to generate insightful solutions than if they are kept from sleeping (Wagner, Gais, Haider, Verleger, & Born, 2004; Yordanova, Kolev, Wagner, Born, & Verleger, 2012). This latter finding supports the idea that creativity, decision-making and problem-solving skills may be enhanced by getting adequate sleep (Leitzell, 2008). Sleep is also crucial to the formation of long-term memories (Rasch & Born, 2008; Tamminen, Payne, Stickgold, Wamsley, & Gaskell, 2010), perhaps by enhancing neural plasticity and increasing the formation of new neural networks.
Circadian Cycles: The Biological Clock
Like many other biological functions, sleep and waking follow a daily, or circadian, cycle (from the Latin expression circa diem, meaning "about a day"). Circadian rhythms are a fundamental adaptation to the 24-hour solar cycle of light and dark, found not only in humans and other animals, but also in plants and even one-celled organisms. The human biological clock is largely governed by a tiny cluster of neurons just above the optic chiasm in the lower region of the hypothalamus known as the suprachiasmatic nucleus (SCN) (Evans, Pan, Liu, & Welsh, 2012). The SCN receives information about the daily light and dark cycles via a direct pathway from the retina of the eye (Pobojewski, 2007). In response to the light and dark cycles detected by the eye, the SCN releases specific neurotransmitters that control our body's temperature, metabolism, blood pressure, hormone levels, and hunger, which vary predictably through the course of the day.
Working late at night runs counter to the body's natural circadian rhythm. The result is that tens of millions of night workers around the world find themselves trying to work while feeling sleepy and having difficulty paying attention (Price, 2011). This is an especially critical problem among workers whose jobs require that they remain alert and able to make split-second decisions. For example, in the spring of 2011 a number of air traffic controllers were found late at night to be asleep on the job. In one case, several large jets had to land at Reagan National Airport in Washington without any assistance from the control tower whose operator was fast asleep.
The Rhythms of Sleep
"Going to sleep" means losing awareness and failing to respond to a stimulus that would produce a response in the waking state. Throughout the course of an average night, we move through several unique stages of sleep, each defined by changes in brain waves.
After an initial twilight phase, characterized by irregular, low-voltage alpha waves - a brain wave pattern mirroring the sense of relaxed wakefulness experienced while lying on the beach or resting after a big meal - the sleeper moves through four stages of sleep. Beginning with Stage 1 of sleep, where brain waves are tight and of very low amplitude (height) - resembling those recorded when a person is alert or excited - each following sleep stage is progressively deeper, with heart rate, breathing rate, blood pressure, and body temperature getting as low as they will get during the night by Stage 4.
After an hour of falling asleep, the sleeper begins to ascend from Stage 4 sleep to Stage 3, Stage 2, and back to Stage 1 - a process that takes about 40 minutes. The brain waves return to the low-amplitude, saw-toothed shape characteristic of Stage 1 sleep and waking alertness. Heart rate and blood pressure also increase, yet the muscles are more relaxed than at any other point in the sleep cycle, and the person is very difficult to awaken. The eyes move rapidly under closed eyelids. This rapid-eye movement (REM) sleep stage is distinguished from all other stages of sleep (called non-REM or NREM) that precede and follow it.
Sleep Deprivation
Between one-third and one-half of all adults regularly fail to get enough sleep. According to the National Sleep Foundation, adolescents need at least 9 hours of sleep a night but 80% of them get less sleep than that (National Sleep Foundation, 2006). As a result, at least once a week 28% of high school students fall asleep in class. Another 22% fall asleep while doing homework and 14% arrive late or miss school entirely because they oversleep. Thus, it is not surprising that chronic sleep deprivation among adolescents results in depressed mood, diminished attention, reduced arousal, and lower test scores (Beebe, Rose, & Amin, 2010; Short, Gradisar, Lack, & Wright, 2013).
Despite common beliefs, people do not adapt to chronic sleep loss. Extensive research shows that losing an hour or two of sleep every night, week after week, month after month, makes it more difficult for people to pay attention (especially to monotonous tasks) and to remember things (Van Dongen, Belenky, & Kreuger, 2011). Reaction time slows down, behavior becomes unpredictable, logical reasoning is impaired, and accidents and errors in judgment increase, while productivity and the ability to make decisions decline (Howard et al., 2014; Oken & Salinsky, 2007; Scott, McNaughton, & Polman, 2006). These findings have important implications. For example, experts estimate that sleep loss is a contributing factor to more than 200,000 automobile accidents each year in the United States, resulting in more than a thousand deaths and tens of thousands of injuries. Research suggests that driving while sleepy is just as dangerous as driving while drunk (Orzel-Gryglewska, 2010). Combining sleep deprivation with drinking, even moderate drinking, is especially dangerous (Oken & Salinsky, 2007).
Sleep deprivation may also affect the performance of people in high-risk positions such as nuclear power plant operators, who often have to make critical decisions on short notice. In 1979, there was an accident at the nuclear power plant at Three Mile Island, Pennsylvania, in which human error transformed a minor mishap into a major nuclear disaster. Hospital residents who work long hours without rest experience twice as many failures of attention while working at night compared to residents who work shorter shifts. They make over one-third of serious medical errors regarding patients, including five times as many serious diagnostic mistakes that could be life-threatening (Landrigan et al., 2004; Landrigan, 2005). To put the state of exhaustion into further perspective, residents working heavy schedules perform similarly on cognitive tasks to people with blood alcohol levels between 0.04% and 0.05% - the level reached when an average-sized man consumes three beers in a single hour (Arnedt, Owens, Crouch, Stahl, & Carskadon, 2005).
Lack of sleep has been shown to contribute to such diseases as heart attacks, asthma, strokes, high blood pressure, and diabetes (Sabanayagam & Shankar, 2010). In children, insufficient sleep is associated with increased risk of being overweight (Lumeng et al., 2007). Sleep deprivation is also clearly related to depression in high school and college students. According to Mary Alice Carskadon, a leading researcher in the area of sleep among college students, "Every study we have ever done over the past decade on high school and college students shows the less sleep they get the more depressed mood they report" (Markel, 2003, p. D6). Even for college students who are not depressed, a lack of sleep results in lower academic performance and an increased risk for accidents and injury (Gilbert & Weaver, 2010; Marhefka, 2011).
According to a well-known sleep researcher, Dr. William Dement, one way to reduce your sleep debt is to take short naps. Even a 20-minute nap can increase alertness, reduce irritability, and improve efficiency, while 1-hour naps lead to more marked increases in performance (Leitzell, 2008; S. C. Mednick et al., 2002). Even in very young children, naps appear to play a protective role by reducing the number of accidental falls (Boto et al., 2012).
Sleep Disorders
At any given time, at least 50 million Americans suffer from chronic, long-term sleep disorders; and 20 million other Americans experience occasional sleep problems. A study of 72,000 female nurses found that women who sleep either too much (more than 9 hours) or too little (less than 5 hours) have an increased risk for heart disease. Although researchers could not determine exactly why this relationship was present, they suggested the tendency to sleep too much or too little might be indicative of underlying medical conditions (Ayas et al., 2003). The scientific study of typical sleep patterns has yielded further insights into several sleep disorders, including: sleeptalking and sleepwalking, nightmares and night terrors, insomnia, apnea, and narcolepsy.
Sleeptalking, Sleepwalking, and Night Terrors
Sleeptalking and sleepwalking usually occur during Stage 4. Both are more common among children than adults: About 20% of children have at least one episode of either sleepwalking or sleeptalking. Boys are more likely to walk in their sleep than girls. Contrary to popular belief, waking a sleepwalker is not dangerous (in fact, it may be more dangerous not to wake the person), but because sleepwalking commonly takes place during a very deep stage of sleep, waking a sleepwalker is not easy (National Sleep Foundation, 2005).
Sometimes sleep can be frightening, when people experience nightmares or night terrors, also known as sleep terrors. Although both these phenomena are bad dreams, they are very different (Christophersen & VanScoyoc, 2013). Nightmares occur during REM sleep and we can remember them in the morning. These frightening dreams are also very common; virtually everyone has them occasionally. Night terrors, a form of nocturnal fright that makes the dreamer suddenly sit up in bed - often screaming out in fear - occur during NREM sleep. Like sleepwalking, night terrors and nightmares occur more frequently among young children. People generally cannot be awakened from night terrors and will push away anyone trying to comfort them. Unlike nightmares, night terrors cannot be recalled the next morning.
The frequency of nightmares and night terrors increases for both children and adults during times of stress (Schredl, Biemelt, Roos, Dunkel, & Harris, 2008) though neither nightmares nor night terrors alone indicate psychological problems. Anxious people have no more nightmares than other people do. However, people whose nightmares stem from a traumatic experience, such as posttraumatic stress disorder, may be plagued by terrifying nighttime episodes for years (Pigeon, Campbell, Possemato, & Ouimette, 2013).
Insomnia, Apnea, and Narcolepsy
Insomnia, the inability to fall or remain asleep, afflicts approximately 30% of adults around the world, especially women and other adults (T. Roth, 2007). Most episodes of insomnia grow out of stressful events and are temporary (Cano, Mochizuki, & Saper, 2008). But for as much as 20% of the population, insomnia is a persistent disruption that result in decreased quality of life and health problems (Haario, Rahkonen, Laaksonen, Lahelma, & Lallukka, 2013; Karlson, Gallagher, Olson, & Hamilton, 2013; T. Roth, 2007).
Another sleep disorder, obstructive sleep apnea, affects 10 to 12 million Americans, many of whom have inherited the condition (Khalyfa, Serpero, Kheirandish-Gozal, Capdevila, & Gozal, 2011). Apnea is associated with breathing difficulties at night: In severe cases, the victim actually stops breathing after falling asleep. When the level of carbon dioxide in the blood rises to a certain point, apnea sufferers are spurred to a state of arousal just short of waking consciousness. Because this process may happen hundreds of times a night, apnea patients typically feel exhausted and fall asleep repeatedly the next day. They may also complain of depression, sexual dysfunction, difficulty concentrating, and headaches (El-Ad & Lavie, 2005; Strollo & Dave, 2005). Moreover, sleep-related breathing disorders have been shown to be related to hyperactivity, conduct disorders, aggressiveness among children and adolescents, and even nocturnal eating (Amchenstev, Kurugundla, & Lombardo, 2010; Chervin, Killion, Archbold, & Ruzicka, 2003). Depending on its severity, sleep apnea can also double or triple the risk of having a stroke or dying (Muraja-Murro et al., 2013; Yaggi et al., 2005).
Too much sleep has serious repercussions as well. Narcolepsy is a hereditary disorder whose victims nod off without warning in the middle of a conversation or other alert activity. People with narcolepsy often experience a sudden loss of muscle tone upon expression of any sort of emotion. A joke, anger, sexual stimulation - all bring on the muscle paralysis associated with deep sleep. Suddenly, without warning, they collapse. Another symptom of the disorder is immediate entry into REM sleep, which produces frightening hallucinations that are, in fact, dreams that the person is experiencing while still partly awake. New medications show promise in treating some patients with narcolepsy (Majid & Hirshkowitz, 2010; Dauvilliers et al., 2013).
DREAMS
Every culture, including our own, attributes meaning to dreams. In some cultures, people believe that dreams contain messages from their gods or that dreams predict the future. Psychologists define dreams as visual and auditory experiences that our minds create during sleep. The average person has four or five dreams a night, accounting for about one to two hours of the total time spent sleeping. People awakened during REM sleep report graphic dreams about 80 to 85% of the time (Domhoff, 2003). Less striking dreamlike experiences that resemble normal wakeful consciousness are reported about 50% of the time during NREM sleep.
Most dreams last about as long as the events would in real life; they do not flash on your mental screen just before waking, as was once believed. Generally, dreams consist of a sequential story or a series of stories. Stimuli, both external (such as a train whistle or a low-flying airplane) and internal (such as hunger pangs), may modify an ongoing dream, but they do not initiate dreams. Often, dreams are so vivid that it is difficult to distinguish them from reality (Domhoff, 2005).
Why Do We Dream?
Psychologists have long been fascinated by dream activity and the contents of dreams, and a number of explanations have been proposed.
Dreams as Unconscious Wishes
Sigmund Freud (1900), the first modern theorist to investigate this topic, called dreams the "royal road to the unconscious." Believing that dreams represent unfulfilled wishes, he asserted that people's dreams reflect the motives guiding their behavior - motives of which they may not be consciously aware. Freud distinguished between the manifest, or surface, content of dreams and their latent content - the hidden, unconscious thoughts or desires that he believed were expressed indirectly through dreams.
In dreams, according to Freud, people permit themselves to express primitive desires that are relatively free of moral controls. For example, someone who is not consciously aware of hostile feelings toward a sister may dream about murdering her. However, in a dream, such hostile feelings may be censored and transformed into a symbolic form. For example, the desire to do away with one's sister (the dream's latent content) may be recast into the dream image of seeing her off at a train "terminal" (the dream's manifest content). According to Freud, this process of censorship and symbolic transformation accounts for the highly illogical nature of many dreams. Deciphering the disguised meanings of dreams remains one of the principal tasks of many psychoanalysts (Hill, Liu, Spangler, Sim, & Schottenbauer, 2008). Freud's pioneering work, focused on exploring the meaning of dreams, paved the way for contemporary investigations of dream content (Schneider, 2010).
Dreams and Information Processing
A completely different explanation for dreaming emerged in the later part of the 20th century with the advent of information processing theory. This view holds that in our dreams, we reprocess information gathered during the day as a way of strengthening memories of information that is crucial to survival (Ji & WIlson, 2007; Wagner & Born, 2008). During our waking hours, our brains are bombarded with sensory data. We need a "time out" to decide what information is valuable, whether it should be filed in long-term memory, where it should be filed, and what information should be erased so that it doesn't clutter neural pathways (Payne & Nadel, 2004). According to this view, dreams seem illogical because the brain is rapidly scanning old files and comparing them with new, unsorted "clippings."
In support of this view, research has demonstrated that both humans and non-humans spend more time in REM sleep after learning difficult material; furthermore, interfering with REM sleep immediately after learning severely disrupts the memory for the newly learned material (C. T. Smith, Nixon, & Nader, 2004; Wetzel, Wagner, & Balschun, 2003). Brain-imaging studies have also demonstrated that the specific area of the brain most active while learning new material is also active during subsequent REM sleep (Maquet et al., 2000).
Dreams and Waking Life
Still another theory maintains that dreams are an extension of the conscious concerns of daily life in altered (but not disguised) form (Domhoff, 2003). Research has shown that what people dream about is generally similar to what they think about and do while awake (Mathes & Schredl, 2013; Domhoff, 2010). For example, a parent who's having problems with a child may dream about childhood confrontations with his or her own parents. Dream content is also related to where you are in your sleep cycle, what you've been doing before you sleep, your gender, your age, socioeconomic status and cultural background (Mazandarani, Aguilar-Vafaie, & Domhoff, 2013). For example, although the dreams of men and women have become more similar over the last several decades, men more often dream about weapons, unfamiliar characters, male characters, aggressive interactions, and failure outcomes, whereas women are more likely to dream about being the victims of aggression (Bursik, 1998). Dream content also appears to be relatively consistent for most individuals, displaying similar themes across years and even decades (Domhoff & Schneider, 2008).
Dreams and Neural Activity
Research using advanced brain-imaging techniques has revealed that the limbic system, which is involved with emotions, motivations, and memories, is very active during dreams; so, to a lesser extent, are the visual and auditory areas of the forebrain that process sensory information. However, areas of the forebrain, including the prefrontal cortex, involved in working memory, attention, logic, and self-monitoring are relatively inactive during dreams (Dang-Vu, Schabus, Desseilles, Schwartz, & Maquet, 2007; Dresler et al., 2012). This fact might explain the highly emotional texture of dreams, as well as the bizarre imagery and the loss of critical insight, logic, and self-reflection.
The Activation-Synthesis Theory of Dreaming, proposed over 30 years ago (Hobson & McCarley, 1977), provides a model of how the various brain centers may interact to produce what we experience as a dream. Dreams are the most common alteration of normal consciousness; they occur naturally under normal conditions.
DRUG-ALTERED CONSCIOUSNESS
The use of psychoactive drugs - substances that change people's moods, perceptions, mental functioning, or behavior - is almost universal. In nearly every known culture throughout history, people have sought ways to alter waking consciousness. Many legal and illegal drugs currently available have been used for thousands of years. Of all psychoactive substances, alcohol has the longest history of widespread use. Archaeological evidence suggests that Late-Stone-Age groups began producing mead (fermented honey flavored with sap or fruit) about 10,000 years ago. The Egyptians, Babylonians, Greeks, and Romans viewed wine as a "gift from the gods." Wine is frequently praised in the Bible, and drinking water is hardly mentioned. As recently as the 19th century, most people in Western civilizations drank alcohol with every meal (including breakfast) and between meals, as a "pick-me-up," as well as on social and religious occasions.
Is the use of drugs today different from the drug use in other societies and times? In many ways, the answer is yes. First, motives for using psychoactive drugs have changed. In most cultures, psychoactive substances have been used as part of religious rituals, as medicines and tonics, as nutrient beverages, or as culturally approved stimulants (much as we drink coffee). By contrast, the use of alcohol and other drugs in contemporary society is primarily recreational. The French often drink wine with dinner, the British have their pubs, and Greeks have their festivals. Americans most often imbibe in settings specifically designed for recreation and inebriation: bars, clubs, and cocktail parties. In addition, people use and abuse drugs privately and secretly in their homes, sometimes without the knowledge of their family and friends - leading to hidden addiction.
Second, the drugs themselves have changed. Modern psychoactive substances often are stronger than those used in other cultures and times. For most of Western history, wine (12% alcohol) was often diluted with water. Hard liquor (40%-75% alcohol) appeared only in the 10th century C.E., and the heroin available on the streets today is stronger and more addictive than that which was available in the 1930s and 1940s.
In addition, new, synthetic drugs such as "Meth" or "Crystal Meth" (methamphetamine) appear regularly, with unpredictable consequences. Because the source, the psychoactive ingredients, and any possible contaminants are unknown in these drugs, the symptoms, toxicity, and short- or long-term consequences are also unknown - making them especially dangerous. Finally, scientists and the public know more about the effects of psychoactive drugs than in the past. Nicotine is an obvious example. The Surgeon General's Report issued in 1964 confirmed a direct link between smoking and heart disease, as well as lung cancer. Subsequent research establishing that cigarettes are harmful not only to smokers, but also to people around them (as a result of secondhand smoke), as well as to their unborn babies (Schick & Glantz, 2005), transformed a personal health decision into a moral issue. Nonetheless, tens of millions of Americans still smoke, and millions of others use drugs they know to be harmful.
Substance Use, Abuse, and Dependence
If we define drugs broadly to include caffeine, tobacco, and alcohol, then most people throughout the world use some type of drug on an occasional or regular basis. Most of these people use such drugs in moderation and do not suffer ill effects. But for some, substance use escalates into substance abuse - a pattern of drug use that diminishes a person's ability to fulfill responsibilities, that results in repeated use of the drug in dangerous situations, or that leads to legal difficulties related to drug use. For example, people whose drinking causes ill health and problems within their families or on their jobs are abusing alcohol. Substance abuse is America's leading health problem (S. Martin, 2001).
The ongoing abuse of drugs, including alcohol, may lead to compulsive use of the substance, or substance dependence, which is also known as addiction. Although not everyone who abuses a substance develops dependence, dependence usually follows a period of abuse. Dependence often includes tolerance, the phenomenon whereby higher doses of the drug are required to produce its original effects or to prevent withdrawal symptoms, the unpleasant physical or psychological effects following discontinuance of the substance. Many organizations publicize self-tests based on these and other elements in the definition of substance abuse. For example, a self-test from the National Council on alcoholism includes the questions, "Can you handle more alcohol now than when you first started to drink?" and "When drinking with other people, do you try to have a few extra drinks the others won't know about?"
The causes of substance abuse and dependence are a complex combination of biological, psychological, and social factors that varies for each individual and for each substance. Also, the development of substance dependence does not follow an established timetable. One person might drink socially for years before abusing alcohol, whereas someone else might become addicted to cocaine in a matter of days.
How Drug Effects Are Studied
The effects of particular drugs are studied under carefully controlled scientific conditions. In most cases, researchers compare people's behavior before the administration of the drug with their behavior afterward, taking special precautions to ensure that any observed changes in behavior are due to the drug alone.
To eliminate research errors based on subject or researcher expectations, most drug experiments use the double-blind procedure, in which some participants receive the active drug while others take a neutral, inactive substance called a placebo. Neither the researchers nor the participants know who is taking the active drug and who is taking the placebo. If the behavior of the participants who actually received the drug differs from the behavior of those who got the placebo, the cause is likely to be the active ingredient in the drug.
Studying drug-altered consciousness is complicated by the fact that most drugs not only affect different people in different ways, but also produce different effects in the same person at different times or in different settings (S. Siegel, 2005). For example, some people are powerfully affected by even small amount of alcohol, whereas others are not. And drinking alcohol in a convivial family setting usually produces somewhat different effects than does consuming alcohol under the watchful eyes of a scientist.
Recently, sophisticated neuroimaging procedures have proved useful for studying drug effects. Techniques such as PET imaging have enabled researchers to isolate specific differences between the brains of addicted and nonaddicted people. For example, the "addicted brain" has been found to differ qualitatively from the nonaddicted brain in a variety of ways, including metabolically and in responsiveness to environmental cues. Investigators have also focused on the role played by neurotransmitters in the addictive process - noting that every addictive drug causes dopamine levels in the brain to increase (Trifilieff & Martinez, 2014). Results like these may lead not only to better understanding of the biological basis of addiction, but also to more effective treatments.
In analyzing drugs and drug use, it is convenient to group psychoactive substances into three categories: depressants, stimulants, and hallucinogens. These categories are not rigid, as the same drug may have multiple effects or different effects on different users, but this division helps organize our knowledge about drugs.
Depressants: Alcohol, Barbiturates, and the Opiates
Depressants are chemicals that retard behavior and thinking either by speeding up or slowing down nerve impulses. Generally speaking, alcohol, barbiturates, and the opiates have depressant effects. People take depressants to reduce tension, to forget their troubles, or to relieve feelings of inadequacy, loneliness, or boredom.
Alcohol
The most frequently used psychoactive drug in Western societies is alcohol. In spite of, or perhaps because of, the fact that it is legal and socially approved, alcohol is America's number-one drug problem. A large-scale survey of adults in the United States found that nearly 9% of those surveyed reported alcohol dependence or abuse in the previous 12 months. More than 30% reported alcohol dependence or abuse sometime in the course of their lives (Hasin, Stinson, Ogburn, & Grant, 2007). More than 25% of high school seniors say they got drunk sometime in the past 30 days; and alcohol is also a significant problem among middle-school students. At least 14 million Americans (more than 7% of the population aged 18 and older) have problems with drinking, including more than 8 million alcoholics, who are addicted to alcohol. Three times as many men as women are problem drinkers. For both sexes, alcohol abuse and addiction is highest in the 18- to 29-year-old age group (Hingson, Heeren, Winter, & Wechsler, 2005; National Institute on Alcohol Abuse and Alcoholism, 2003).
Excessive chronic alcohol use can harm virtually every organ in the body, beginning with the brain, and is associated with impairments in perceptual-motor skills, visual-spatial processing, problem solving, and abstract reasoning (Samokhvalov, Popova, Room, Ramonas, & Rehm, 2010). Alcohol is the leading cause of liver disease and kidney damage, is a major factor in cardiovascular disease, increases the risk of certain cancers, and can lead to sexual dysfunction and infertility. Alcohol is particularly damaging to the nervous system during the teenage years (K. Butler, 2006). The total economic cost of alcohol abuse and dependence in America is estimated at nearly $200 billion annually (National Institutes of Health, n.d.). In addition, alcohol abuse is directly involved in more than 20,000 deaths annually and the number is rising (Kung, Hoyert, Xu, & Murphy, 2008).
The social costs of abusing alcohol are high as well. Alcohol is involved in a substantial proportion of violent and accidental deaths, including suicides, which makes it the leading contributor (after AIDS) to death among young people. Alcohol is implicated in more than two-thirds of all fatal automobile accidents, two-thirds of all murders, two-thirds of all spouse beatings, and more than half of all cases of violent child abuse. Moreover, the use of alcohol during pregnancy has been linked to a variety of birth defects, the most notable being fetal alcohol syndrome. More than 40% of all heavy drinkers die before the age of 65 (compared with less than 20% of nondrinkers). In addition, there is the untold cost in psychological trauma suffered by the nearly 30 million children of alcohol abusers.
What makes alcohol so powerful? Alcohol first affects the frontal lobes of the brain, which figure prominently in inhibitions, impulse control, reasoning, and judgment (Zahr, Pitel, Chanraud, & Sullivan, 2010). As consumption continues, alcohol impairs functions of the cerebellum, the center of motor control and balance (Manto & Jacquy, 2002). Eventually, alcohol consumption affects the spinal cord and medulla, which regulate such involuntary functions as breathing, body temperature, and heart rate. A blood-alcohol level of 0.25% or more may cause this part of the nervous system to shut down and may severely impair functioning; slightly higher levels can cause death from alcohol poisoning.
Even in moderate quantities, alcohol affects perception, motor processes, memory, and judgment. It diminishes the ability to see clearly, to perceive depth, and to distinguish the differences between bright lights and colors, and it generally affects spatial-cognitive functioning - all clearly necessary for driving a car safely. Alcohol interferes with memory storage: Heavy drinkers may also experience blackouts, which make them unable to remember anything that occurred while they were drinking; but even long-term alcoholics show improvements in memory, attention, balance, and neurological functioning after three months of sobriety (R. S. Moser, Frantz, & Brick, 2008).
Heavy drinkers have difficulty focusing on relevant information and ignoring inaccurate, irrelevant information, thus leading to poor judgments, a condition called alcoholic myopia (Schreiber Compo et al., 2011). Dozens of studies demonstrate that alcohol use is correlated with increases in aggression, hostility, violence, and abusive behavior (Giancola, Josephs, Parrott, & Duke, 2010). Thus, intoxication makes people less aware of and less concerned about the negative consequences of their actions, increasing their likelihood to engage in risky behavior. The same principle applies to potential victims. For instance, when women are intoxicated, their ability to accurately evaluate a dangerous situation with a potential male aggressor is diminished, so that their risk of being sexually assaulted increases. Not surprisingly, people who are intoxicated are more likely to engage in unprotected sex than if they were sober (Griffin, Umstattd, & Usdan, 2010). The dangers of alcohol notwithstanding, alcohol continues to be popular because of its short-term effects. As a depressant, it calms the nervous system, much like a general anesthetic (McKim, 2007). Thus, people consume alcohol to relax or to enhance their mood.
It is often experienced as a stimulant because it inhibits centers in the brain that govern critical judgment and impulsive behavior. Alcohol makes people feel more courageous, less inhibited, more spontaneous, and more entertaining. To drinkers, the long-term negative consequences of alcoholism pale beside these short-term positive consequences.
The good news is that since 1977, the overall consumption of alcohol is generally down with only a slight increase in the recent decade due largely to increased consumption of wine (Nekisha, Gerald, Hsiao-ye, & Michael, 2005). Alcohol-related traffic deaths, while still too common, have also declined sharply in recent years.
Binge Drinking on College Campuses
One of the few places today where drunkenness is tolerated, and often expected, is the American college campus. According to the National Center on Addiction and Drug Abuse (NCADA), "In 2005, 67.9 percent of students (approximately 5.3 million students) reported drinking in the past month and 40.1 percent (approximately 3.1 million students) reported binge drinking... The proportion of students reporting frequent binge drinking increased 15.7 percent (from 19.7 percent to 22.8 percent)" (NCADA, 2007, p. 3). "Binge drinking" is defined as five or more drinks in a row for men, four or more drinks for women. "Frequent binge drinking" is defined as binge drinking three or more times in the past two weeks. Nearly half of the college students who drink report that they do so in order to get drunk.
It is not surprising that frequent binge drinkers had more problems, and more serious problems, than other students. Many had missed classes, fallen behind in schoolwork, engaged in unplanned - and unprotected - sex, gotten in trouble with campus police, engaged in vandalism or violence, or been hurt or injured (National Center on Addiction and Drug Abuse, 2007; Stickley, Koyanagi, Koposov, Razvodovsky, & Ruchkin, 2013). Bingers were more likely than other students to have used other drugs, especially cigarettes and marijuana (R. D. Brewer & Swahn, 2005; National Center on Addiction and Substance Abuse, 2007; Pirkle & Richter, 2006). They were 10 times more likely to have driven a car after drinking and more than 15 times more likely to have ridden with a driver who was drunk or high.
The effects of binge drinking are not limited to students who participate. At schools with high binge rates, a majority of students report that they have been unable to study or sleep because of binge drinking. Many sober students have cared for drunken friends, endured drunken insults, and fended off unwanted sexual advances. Yet most are reluctant to report these problems to campus or other authorities. Strict campus alcohol policies have been shown to be effective in reducing binge drinking rates over time (Harris, Sherritt, Van Hook, Wechsler, & Knight, 2010).
Barbiturates
Barbiturates, commonly known as "downers," include such medications as Amytal, Seconal, and phenobarbital. Discovered about a century ago, this class of depressants was first prescribed for its sedative and anticonvulsant qualities. But after researchers recognized in the 1950s that barbiturates had potentially deadly effects - particularly in combination with alcohol - their use declined. Though barbiturates are sometimes prescribed to help people sleep, they actually disrupt the body's natural sleep patterns and cause dependence when used for long periods.
The general effects of barbiturates are strikingly similar to those of alcohol: Taken on an empty stomach, a small dose causes light-headedness, silliness, and poor motor coordination (McKim, 2007), whereas larger doses may bring on slurred speech, loss of inhibition, and increases in aggression. When taken during pregnancy, barbiturates, like alcohol, produce such birth defects as a cleft palate and malformations of the heart, skeleton, and central nervous system (Olney, Wozniak, Farber, Jevtovic-Todorovic, & Bittigau, 2002).
Opiates
Psychoactive substances derived from, or resembling, sap taken from the seedpod of the opium poppy, opiates have a long history of use - though not always abuse. Originating in Turkey, opium spread west around the Mediterranean and east through India into China, where it was used in pill or liquid form in folk medicines for thousands of years. But changes in the way opium and its derivative, morphine, were used opened the door to abuse. In the mid-17th century, when the emperor of China banned tobacco and the Chinese began to smoke opium, addiction quickly followed. During the American Civil War, physicians used a new invention, the hypodermic needle, to administer morphine, a much-needed painkiller for soldiers. In this form, morphine was far more addictive than smoking opium. Heroin - introduced in 1898 as a cure for morphine addiction - created an even stronger dependency.
Morphine compounds are still used in painkillers and other medications, such as codeine cough syrups. The nonmedical distribution of opiates was banned early in the 20th century. After that, a black market for heroin developed.
Heroin and other opiates resemble endorphins, the natural painkillers produced by the body, and occupy many of the same nerve-receptor sites. Heroin users report a surge of euphoria soon after taking the drug, followed by a period of "nodding off" and clouded mental functioning. Regular use leads to tolerance; tolerance may lead to physical dependence. In advanced stages of addiction, heroin becomes primarily a painkiller to stave off withdrawal symptoms. These symptoms, which may begin within hours of the last dose, include profuse sweating; alternating hot flashes and chills with goose bumps resembling the texture of a plucked turkey (hence, the term cold turkey); severe cramps, vomiting, and diarrhea; and convulsive shaking and kicking (as in "kicking the habit").
Heroin abuse is associated with serious health conditions, including fatal overdose, spontaneous abortion, collapsed veins, pulmonary problems, and infectious diseases, especially HIV/AIDS and hepatitis, as a result of sharing needles (Bourgeois, 1999; McCurdy, Williams, Kilonzo, Ross, & Leshabari, 2005; Meade, McDonald, & Weiss, 2009). Brain imaging studies have also shown that prolonged use of heroin may produce structural changes in the brain (M. Li et al., 2013). Perhaps not surprisingly, the highest cause of death among heroin users is overdosing (Degenhardt et al., 2011).
Stimulants: Caffeine, Nicotine, Amphetamines, and Cocaine
The drugs classified as stimulants - caffeine, nicotine, amphetamines, and cocaine - have legitimate uses, but because they produce feelings of optimism and boundless energy, the potential for abuse is high.
Caffeine
Caffeine, which occurs naturally in coffee, tea, and cocoa, belongs to a class of drugs known as xanthine stimulants. When taken in small to moderate doses caffeine has been shown to improve alertness, attention, and performance on simple motor tasks (Einother & Giesbrecht, 2013). However, continued consumption often leads to tolerance, reducing its positive effect on attention and motor performance (Rogers, Heatherley, Mullings, & Smith, 2013).
Caffeine is found in many beverages and nonprescription medications, including pain relievers, cold and allergy remedies, and a wide variety of energy drinks. It is generally considered a benign drug, although large doses - more than five or six cups of strong coffee per day, for example - may cause anxiety, headaches, heart palpitations, insomnia, and diarrhea. Caffeine interferes with prescribed medications, such as tranquilizers and sedatives, and appears to aggravate the symptoms of many psychiatric disorders. It is not clear what percentage of coffee drinkers are dependent on caffeine. Those who are dependent experience tolerance, difficulty in giving it up, and physical and psychological distress, such as headaches, lethargy, and depression, whether the caffeine is in soda, coffee, or tea (Juliano & Griffiths, 2004).
In recent years, beverages combining caffeine and alcohol have become popular, especially among college students. Early evidence suggested these "caffeinated alcoholic beverages" may pose a greater health risk than alcohol or caffeine consumed separately (Howland, Rohsenow, Calise, Mackillop, & Metrik, 2011), prompting the FDA to quickly remove many of these beverages from the market (U.S. Food and Drug Administration, 2010). Among the concerns raised by the consumption of caffeinated alcoholic beverages are an increase in the tendency to engage in risky behaviors, and a strong association with developing alcohol dependence among regular users (Arria, Caldeira, Kasperski, Vincent, Griffiths, & O'Grady, 2011).
Nicotine
Nicotine, the psychoactive ingredient in tobacco, is probably the most dangerous and addictive stimulant in use today. Studies have found that the neurochemical properties of nicotine are similar to those of cocaine, amphetamines, and morphine (Fredrickson, Boules, Lin, & Richelson, 2005). When smoked, nicotine tends to arrive at the brain all at once following each puff - a rush similar to the "high" experienced by heroin users. The smoker's heart rate increases and blood vessels constrict, causing dull skin and cold hands and accelerating the process of wrinkling and aging. Nicotine affects levels of several neurotransmitters, including norepinephrine, dopamine, and serotonin. Depending on the time, the amount smoked, and other factors, it may have sedating or stimulating effects. Symptoms of withdrawal from nicotine include nervousness, difficulty concentrating, both insomnia and drowsiness, headaches, irritability, and intense craving, which continue for weeks and may recur months or even years after a smoker has quit (Haro & Drucker-Colin, 2004).
Despite well-known health risks and strong social pressures, millions of Americans continue to smoke, either for the pleasure of the combined stimulant-sedative effects or to prevent cravings and withdrawal symptoms. Particularly worrisome is that the number of teenagers who start smoking each year has hardly changed and nicotine addiction in young people happens very quickly (DiFranza et al., 2007). Youths aged 12-17 who smoke are about 12 times more likely to use illicit drugs, and 16 times more likely to drink heavily, than their nonsmoking peers (National Household Survey on Drug Abuse, 1998; D. Smith, 2001). The suggestion that nicotine may serve as a "gateway" drug receives some support from research showing that, taken during the adolescent years, nicotine may alter the way specific brain cells respond to serotonin increasing the likelihood of becoming addicted to other drugs (McQuown, 2010).
Amphetamines
Amphetamines are powerful synthetic stimulants, first marketed in the 1930s as a nasal spray to relieve symptoms of asthma. At the chemical level, amphetamines resemble epinephrine, a hormone that stimulates the sympathetic nervous system. During World War II, the military routinely gave soldiers amphetamines in pill form to relieve fatigue. After the war, the demand for "pep pills" grew among night workers, truck drivers, students, and athletes. Because amphetamines tend to suppress the appetite, they were widely prescribed as "diet pills." Today, the only legitimate medical uses for amphetamines are to treat narcolepsy and attention deficit disorder. (Paradoxically, amphetamines have a calming effect on hyperactive children.) They are, however, widely used for nonmedical, "recreational" reasons.
Amphetamines not only increase alertness, but also produce feelings of competence and well-being. People who inject them intravenously report a "rush" of euphoria. After the drug's effects wear off, however, users may "crash" into a state of exhaustion and depression. Amphetamines are habit forming: Users may come to believe that they cannot function without them. High doses can cause sweating, tremors, heart palpitations, anxiety, and insomnia - which may lead people to take barbiturates or other drugs to counteract these effects. Excessive use of amphetamines may cause personality changes, including paranoia, homicidal and suicidal thoughts, and aggressive, violent behavior (Baker & Dawe, 2005). Chronic users may develop amphetamine psychosis, which resembles paranoid schizophrenia and is characterized by delusions, hallucinations, and paranoia.
Methamphetamine - known on the street as "speed" and "fire," or in a crystal, smokable form as "ice," "crystal," "crystal meth," and "crank" - is easily produced in clandestine laboratories from ingredients available over the counter. A variation that was briefly popular around the turn of the 21st century, Ecstasy (methylenedioxymethamphetamine, or MDMA), acts as both a stimulant and a hallucinogen. The name "Ecstasy" reflects the users' belief that the drug makes people love and trust one another, puts them in touch with their own emotions, and heightens sexual pleasure.
Short-term physical effects include involuntary teeth clenching (which is why users often wear baby pacifiers around their neck or suck lollipops), faintness, and chills or sweating. Although early research on Ecstasy with primates suggested that even short-term recreational use could have long-term harmful consequences, more recent studies have not verified evidence of permanent damage from short-term use (Navarro & Maldonado, 2004; Ricaurte, Yuan, Hatzidimitriou, Cord, & McCann, 2003; Sumnall, Jerome, Doblin, & Mithoefer, 2004). There is still some reason to be concerned, however, especially by heavy use. Animal research going back more than 20 years shows that high doses of methamphetamine damage the axon terminals of dopamine- and serotonin-containing neurons (National Institute on Drug Abuse, 2005). Increased aggression in rats has been observed following a single low dose administration of methamphetamine (Kirilly et al., 2006). One study also found that the recreational use of Ecstasy may lead to a decrease in intelligence test scores (Gouzoulis-Mayfrank et al., 2000), and heavy use of MDMA has been associated with a decline in visual memory (Back-Madruga et al., 2003). Moreover, the use of Ecstasy during pregnancy has been associated with birth defects (McElhatton, Bateman, Evans, Pughe, & Thomas, 1999). Increased public awareness of the potential dangers associated with Ecstasy explains in part the sharp decline in its usage after 2000 (Johnston, O'Malley, Bachman, & Schulenberg, 2013).
Cocaine
First isolated from cocoa leaves in 1885, cocaine came to be used widely as a topical anesthetic for minor surgery (and still is, for example, in the dental anesthetic Novocain). Around the turn of the century, many physicians believed that cocaine was beneficial as a general stimulant, as well as a cure for excessive use of alcohol and morphine addiction. Among the more famous cocaine users was Sigmund Freud. When he discovered how addictive cocaine was, Freud campaigned against it, as did many of his contemporaries, and ingesting the drug fell into disrepute.
Cocaine made a comeback in the 1970s in such unlikely places as Wall Street, among investment bankers who found that the drug not only made them high, but also allowed them to wheel and deal around the clock with little sleep (Califano, 1999). In the white-powdered form that is snorted (street names include "coke" and "snow"), it became a status drug; the amphetamine of the wealthy. In the 1980s, a cheaper, smokable, crystallized form known as "crack" (made from the byproducts of cocaine extraction) appeared in inner-city neighborhoods. Crack reaches the brain in less than 10 seconds, producing a high that lasts from 5 to 20 minutes, followed by a swift and equally intense depression. Users report that crack leads to almost instantaneous addiction. Addiction to powdered cocaine, which has longer effects, is not inevitable, but is likely. Babies born to women addicted to crack and cocaine often are premature or have low-birth weight, may have withdrawal symptoms, and enter school with subtle deficits in intelligence and language skills (Bandstra, Morrow, Mansoor, & Accornero, 2010).
On the biochemical level, cocaine blocks the reabsorption of the neurotransmitter dopamine, which is associated with awareness, motivation, and, most significantly, pleasure (Bressan & Crippa, 2005). Excess dopamine intensifies and prolongs feelings of pleasure - hence the cocaine user's feelings of euphoria. Normally, dopamine is reabsorbed, leading to feelings of satiety or satisfaction; dopamine reabsorption tells the body, "That's enough." But cocaine short-circuits this feeling of satisfaction, in effect telling the body, "More!" The addictive potential of cocaine may be related to the fact that cocaine alters the way brain cells produce and respond to dopamine, so that an increasing amount of cocaine is needed to get the same high in the future (Perez, Ford, Goussakov, Stutzmann, & Hu, 2011).
Hallucinogens and Marijuana
Certain natural or synthetic drugs can cause striking shifts in perception of the outside world or, in some cases, can cause their users to experience imaginary landscapes, settings, and beings that may seem more real than the outside world. Because such experiences resemble hallucinations, the drugs causing them are known as hallucinogens. The hallucinogens include lysergic acid diethylamide (LSD, also known as "acid"), mescaline, peyote, psilocybin, and salvia. Marijuana is sometimes included in this group, although its effects are normally less powerful. How many cultural groups have used hallucinogens is not known. Historians believe that Native Americans have used mescaline, a psychedelic substance found in the mushroom-shaped tops or "buttons" of peyote cactus, for at least 8,000 years.
By contrast, the story of lysergic acid diethylamide (LSD), the drug that triggered the current interest in the hallucinogens, began in the 20th century. In 1943, an American pharmacologist synthesized LSD, and after ingesting it, he reported experiencing "an uninterrupted stream of fantastic pictures and extraordinary shapes with an intense, kaleidoscopic play of colors." His report led others to experiment with LSD as an artificial form of psychosis, a painkiller for terminal cancer patients, and a cure for alcoholism in the 1950s (Ashley, 1975). LSD came to public attention in the 1960s, when Harvard psychologist Timothy Leary, after trying the related hallucinogen psilocybin, began spreading the "Turn On, Tune In, Drop Out" gospel of the hippie movement. Use of LSD and marijuana declined steadily in the 1970s, but became popular once again in the 1990s, especially with high school and college students (Janofsky, 1994).
About an hour after ingesting LSD, people begin to experience an intensification of sensory perception, loss of control over their thoughts and emotions, and feelings of depersonalization and detachment. Some LSD users say that things never looked or sounded or smelled so beautiful; others have terrifying, nightmarish visions. Some users experience a sense of extraordinary mental lucidity; others become so confused that they fear they are losing their minds. The effects of LSD are highly variable, even for the same person on different occasions.
"Bad trips," or unpleasant experiences, may be set off by a change in dosage or an alteration in setting or mood. Flashbacks, or recurrences of hallucinations, may occur weeks after ingesting LSD. Other consequences of frequent use may include memory loss, paranoia, panic attacks, and the risk of psychiatric breakdown (Parrott, 2012).
Unlike depressants and stimulants, LSD and the other hallucinogens do not appear to produce withdrawal effects. If LSD is taken repeatedly, tolerance builds up rapidly: After a few days, no amount of the drug will produce its usual effects, until its use is suspended for about a week (McKim, 2007). This effect acts as a built-in deterrent to continuous use, which helps explain why LSD is generally taken episodically, rather than habitually.
Marijuana
Marijuana is a mixture of dried, shredded flowers and leaves of the hemp plant Cannabis sativa. Unlike LSD, marijuana usage has a long history. In China, cannabis has been cultivated for at least 5,000 years. The ancient Greeks knew about its psychoactive effects; and it has been used as an intoxicant in India for centuries. But only in the 20th century did marijuana become popular in the United States.
Although the active ingredient in marijuana, tetrahydrocannabinol (THC), shares some chemical properties with hallucinogens like LSD, it is far less potent. Marijuana smokers report feelings of relaxation; heightened enjoyment of food, music, and sex; a loss of awareness of time; and on occasion, dreamlike experiences. As with LSD, experiences are varied. Many users experience a sense of well-being, and some feel euphoric, but others become suspicious, anxious, and depressed.
Marijuana has direct physiological effects, including dilation of the blood vessels in the eyes, making the eyes appear bloodshot; a dry mouth and coughing (because it is generally smoked); increased thirst and hunger; and mild muscular weakness, often in the form of drooping eyelids (Donatelle, 2004). The use of marijuana during pregnancy has been associated with depression, attention disorders, and delinquency in children born to mothers who smoked marijuana while pregnant (Day, Leech, & Goldschmidt, 2011). Among the drug's psychological effects is a distortion of time, which appears to be related to the impact marijuana has on specific regions of the brain (D. S. O'Leary et al., 2003). Feelings that minutes occur in slow motion or that hours flash by in seconds are common. Marijuana also produces alterations in short-term memory, attention, and decision making (Dougherty, 2013). In addition, neuroimaging studies have shown that chronic marijuana use may lead to poor decision making by altering the way specific brain centers respond to negative consequences (Wesley, Hanlon, & Porrino, 2011).
While under the influence of marijuana, people often lose the ability to remember and coordinate information, a phenomenon known as temporal disintegration. For instance, someone who is "high" on marijuana may forget what he or she was talking about in midsentence. While high, marijuana users have shortened attention spans and delayed reactions, which contribute to concerns about their ability to drive a car or to study or work effectively (National Institute on Drug Abuse, 2004).
Is marijuana a "dangerous" drug? This question is the subject of much debate in scientific circles as well as public forums. Its recent legalization in some U.S. states has led some to question its prohibition in other states. On the one hand are those who contend that marijuana can be psychologically if not physiologically addictive (Haney et al., 2004; Levin et al., 2004); that frequent, long-term use has a negative impact on learning and motivation; and that legal prohibitions against marijuana should be continued. The evidence for cognitive or psychological damage is mixed. One study of college students showed that critical skills related to attention, money, and learning are impaired among people who use marijuana heavily, even after discontinuing its use for at least 24 hours (National Institute on Drug Abuse, 2004). Another found that marijuana use is associated with microscopic reducations in the white matter of the frontal lobes, leading to an increase in impulsive behavior (Gruber, Silveri, Dahlgren, & Yurgelun-Todd, 2011). On the other hand are those who maintain that marijuana is less harmful than the legal drugs alcohol and nicotine. They argue that the criminalization of marijuana forces people to buy unregulated cannabis from illegal sources, which means that they might smoke "pot" contaminated with more harmful substances. Moreover, some evidence indicates that marijuana can relieve some of the unpleasant side effects of chemotherapy and can reduce suffering among terminal cancer patients. In short, the jury is still out, and the debate over marijuana is likely to continue (Cohen, 2009).
Explaining Abuse and Addiction
Some people drink socially and never develop a problem with alcohol, whereas others become dependent or addicted. Some experiment with crack or use "club drugs," whereas others "just say no." Each year, millions of Americans stop smoking cigarettes. Given the known hazards of smoking, why do a significant number of them relapse after months, even years, of not smoking?
The causes of substance abuse and dependence are complex; the result of a combination of biological, psychological, social, and cultural factors that varies from person to person, and depend on what psychoactive drug or drugs are used. But psychologists have identified a number of factors that, especially in combination, make it more likely that a person will abuse drugs.
Biological Factors
There is mounting evidence that "At least half of a person's susceptibility to drug addiction can be linked to genetic factors" (Price, 2008, p. 16; see also Nurnberger & Bierut, 2007). The evidence for a genetic predisposition for alcohol abuse is strong, though there is not just one gene that is involved (Nurnberger & Bierut, 2007). People whose biological parents have alcohol-abuse problems are more likely to abuse alcohol - even if they are adopted and raised by people who do not abuse alcohol. Identical twins are far more likely to have similar patterns relating to alcohol, tobacco, and marijuana use than are fraternal twins (Gordis, 1996; C. Lerman et al., 1999; I-C. Liu et al., 2004; National Institute on Drug Abuse, 2004a). Even the subjective effects alcohol, tobacco, and marijuana produce on users, such as the degree of euphoria, pleasantness, or unpleasantness, appear to have a strong genetic component (Haberstick, 2011).
Psychologists have not reached consensus on the exact role that heredity plays in a predisposition for alcoholism (or abuse of other substances). Some psychologists point to hereditary differences in enzymes that break down alcohol in the body (Nurnberger & Bierut, 2007). People also appear to differ genetically in their tolerance for alcohol in the blood and in the ways they react to alcohol (Ball, 2004). Heredity can also profoundly affect the quantity of key neurotransmitters in the brain (Nurnberger & Bierut, 2007; Vadasz et al., 2007), as well as the number of receptors that respond to those neurotransmitters (Dalley et al., 2007; Sherva et al., 2008). In turn, those changes in the brain appear to affect the likelihood that a person will become addicted to drugs.
Is addiction a disease, like diabetes or high blood pressure? Alcoholics Anonymous (AA), the oldest and probably the most successful self-help organization in this country, has long endorsed this view. According to the disease model, alcoholism is not a moral issue, but a medical one; and rather than being a sign of character flaws, alcohol abuse is a symptom of a physiological condition. An important aspect of the disease model is that, regardless of the initial source of the addiction, addictive substances dramatically change the brain. Those changes can take months or years to reverse and, during that time, cravings to use the drug can be intense.
The disease model has been applied to many addictions. For example, a relatively new organization called Nicotine Anonymous, dedicated to helping smokers quit, now operates over 450 active groups in the United States and additional groups in 35 other countries (Nicotine Anonymous, 2008). To some degree, the disease model has become part of conventional wisdom: Many Americans view substance abuse as a biological problem, often the result of "bad" genes, which requires medical treatment. Not all psychologists agree, however. Problems with alcohol are better described as a continuum, ranging from mild to severe dependence with many stages in between. The either/or view tends to discourage people from seeking help until their problems have become severe and are more difficult to overcome, and to stigmatize those who go through cycles of sobriety and relapse as weak and contemptible, emphasizing their setbacks rather than their success. It is more appropriate to consider addiction to have a physical basis but important psychological, social, and cultural implications as well.
Psychological, Social, and Cultural Factors
Whether a person uses a psychoactive drug and what effects that drug has depends in part on the person's expectations, the social setting, and cultural beliefs and values. For instance, one survey found that the principle reason American college students drink alcohol, smoke cigarettes, or use other drugs to reduce stress, forget about their problems, and to fit in socially (National Center on Addiction and Substance Abuse, 2007).
The environment in which a child grows up also shapes attitudes and beliefs about drugs. It also appears to play a larger role than does heredity in determining whether an individual starts to drink, smoke, or use other drugs, though "genetic factors are more influential in determining who progresses to problem use or abuse" (National Center on Addiction and Substance Abuse, 2007, p. 42). For example, children whose parents do not use alcohol tend to abstain or drink only moderately; children whose parents abuse alcohol tend to drink heavily (Chassin, Pitts, Delucia, & Todd, 1999; Chassin, Flora, & King, 2004). Parents are not the only family influence; some research indicates that siblings' and peers' attitudes and behavior have as much or more impact on young people than parents do (Ary, Duncan, Duncan, & Hops, 1999; J. R. Harris, 1998).
Culture, too, may steer people toward or away from alcohol. Parents and spouses may introduce people by example to a pattern of heavy drinking. Alcohol is also more acceptable in some ethnic cultures than in others - for example, many religions frown on the excessive use of alcohol, and Muslims, Mormons, conservative Baptists, and Seventh-Day Adventists prohibit it.
In sum, many researchers believe that a full understanding of the causes of alcoholism and other drug addictions will not be achieved unless we take account of a wide variety of factors: heredity, personality, social setting, and culture.
As we have seen, a wide variety of psychoactive drugs may alter consciousness, often with negative consequences such as abuse and addiction.
MEDITATION AND HYPNOSIS
At one time, Western scientists viewed meditation and hypnosis with great skepticism. However, research has shown that both techniques can produce alterations in consciousness that can be measured through such sophisticated methods as brain imaging.
Meditation
For centuries, people have used various forms of meditation to experience an alteration in consciousness. Each form of meditation focuses on the mediator's attention in a slightly different way. Zen meditation concentrates on respiration, for example, whereas Sufism relies on frenzied dancing and prayer. In transcendental meditation (TM), practitioners intone a mantra, which is a sound, specially selected for each person, to keep all other images and problems at bay and to allow the meditator to relax more deeply. The fact that meditation may take many different forms presents one of the challenges facing psychologists who study meditation (Caspi & Burleson, 2005; Desbordes et al., 2014). Some forms of meditation result in a restful, yet fully alert state that enables the self-regulation of one's emotions. Other forms lead to a state of mindfulness, which is "a full-spectrum awareness of the present moment just as it is, accepting whatever is happening simply because it is already happening" (Kabat-Zinn, 2006, p. 61).
In all its forms, meditation suppresses the activity of the sympathetic nervous system which is the part of the nervous system that prepares the body for strenuous activity during an emergency. Meditation also lowers the rate of metabolism, reduces heart and respiratory rates, and decreases blood lactate, a chemical linked to stress. Alpha brain waves (which accompany relaxed wakefulness) increase noticeably during meditation. Not surprisingly, brain-imaging studies indicate that practicing meditation activates brain centers involved in attention and regulation of the autonomic nervous system activity (Cahn & Polich, 2006; Jindal, Gupta, & Das, 2013).
Meditation has been used to treat certain medical problems, especially so-called functional complaints (those for which no physical cause can be found). For example, stress often leads to muscle tension and, sometimes, to pressure on nerves - and pain. Relaxation techniques such as meditation may bring relief of such physical symptoms (Blanchard et al., 1990; Moriconi, 2004). Other evidence suggests that meditation may be useful in treating children diagnosed with attention-deficit hyperactive disorder, and in helping their parents manage the additional stress often placed on their families (Harrison, Manocha, & Rubia, 2004). Studies have also shown that mindfulness-meditation is effective in helping people stop using drugs, and in the prevention of relapses among past drug users (Witkiewitz, Marlatt, & Walker, 2005). Moreover, meditation techniques have shown promise in treating veterans with chronic posttraumatic stress disorder (Bormann, Thorp, Wetherell, Golshan, & Lang, 2013). Finally, some evidence indicates that meditation may increase the effectiveness of the immune system (R. J. Davidson et al., 2003; Pace et al., 2009).
Besides physiological benefits, research has shown that even brief periods of meditation can reduce fatigue, anxiety, and blood pressure, and improve mood, visual-spatial processing, and memory (Zeidan, 2010).
Hypnosis
In mid-18th-century Europe, Anton Mesmer, a Viennese physician, fascinated audiences by putting patients into trances to cure their illnesses. Mesmerism - now known as hypnosis - was initially discredited by a French commission chaired by Benjamin Franklin (Forrest, 2002). But some respectable 19th-century physicians revived interest in hypnosis when they discovered that it could be used to treat certain forms of mental illness. Nevertheless, even today considerable disagreement persists about how to define hypnosis.
Hypnotic Suggestions
Individuals vary in their susceptibility to hypnosis. Several studies have shown that although susceptibility to hypnosis is not related to personal characteristics such as trust, gullibility, submissiveness, and social compliance, it is related to the ability of an individual to dissociate, or become absorbed in reading, music, and daydreaming (Terhune, Cardena, & Lindgren, 2011).
One measure of susceptibility is whether people respond to hypnotic suggestion. Some people who are told that they cannot move their arms or that their pain has vanished do, in fact, experience paralysis or anesthesia; if told that they are hearing a certain piece of music or are unable to hear anything, they may hallucinate or become deaf temporarily (Montgomery, Duhamel, & Redd, 2000). But, contrary to rumors, hypnotic suggestion cannot force people to do something foolish and embarrassing - or dangerous - against their will.
Another measure of the success of hypnosis is whether people respond to posthypnotic commands. For example, under hypnosis, a person suffering from back pain may be instructed that when he feels a twinge, he will imagine that he is floating on a cloud, his body is weightless, and the pain will stop - a technique also called "imaging." A runner may be told that when she pulls on her ear, she will block out the noise of the crowd and the runners on either side of her to heighten her concentration - a form of self-hypnosis. As the last example suggests, hypnosis has become increasingly popular among professional athletes and their weekend counterparts (Edgette & Rowan, 2003; Liggett, 2000).