EMOTIONS AND STRESS SYNDROME. NOTION ABOUT PSYCHOACTIVE DRUGS

 

Role of emotional and volitional processes in forming bechavior

Theories of Emotion

 

Emotion is made up of three components; physiological arousal, expressive behaviors, and conscious experience. One of the oldest theoretical controversies regarding emotion focuses on the timing of our feelings in relation to the physiological responses that accompany emotion. William James and Carl Lange proposed that we feel emotion after we notice our physiological responses. Walter Cannon and Philip Bard believed that we feel emotion at the same time that our bodies respond. A third, more recent, theory, the Schachter-Singer two-factor theory, focuses on the interplay of the emotions rather than the timing of the emotions. It states that there are only two components of emotion, physical arousal and a cognitive label.

 

Embodied Emotion

 

Emotions and the Autonomic Nervous System

Emotions are both psychological and physiological. Much of the physiological activity is controlled by the autonomic nervous system’s sympathetic (arousing) and parasympathetic (calming) divisions. Our performance on a task is usually best when arousal is moderate, though this varies with the difficulty of the task.

 

Physiological Similarities Among Specific Emotions

Three emotions—fear, anger, and sexual arousal—produce similar physiological responses that are nearly indistinguishable to an untrained observer. However, the emotions are felt differently by those experiencing them.

 

Physiological Differences Among Specific Emotions

Emotions stimulate different facial muscles. Additionally, scientists have discovered subtle differences in activity in the brain’s cortical areas, in use of brain pathways, and in secretion of hormones associated with different emotions.

 

Cognition and Emotion

A spillover effect occurs when our arousal response to one event spills over into our response to the following event. Arousal fuels emotion; cognition channels it. Emotional responses are immediate when sensory input goes directly to the amygdala via the thalamus, bypassing the cortex, triggering a rapid reaction that is outside our conscious awareness. 

 

Expressed Emotion

Nonverbal Communication

Much of our communication is through the body’s silent language. Psychologists have studied people’s abilities to detect emotion, even from thin slices of behavior. Research has found that women are typically more sensitive to nonverbal clues than men.

 

Detecting and Computing Emotion

Discerning lies from truth is difficult for the untrained eye. There are certain professionals who are more skilled at detecting emotion. Researchers are studying the role of nonverbal communication during job interviews. In E-mail communications, nonverbal cues are missing which can lead to misinterpretation.

 

Culture and Emotional Expression

Although some gestures are culturally determined, facial expressions, such as those of happiness and fear, are common the world over. In communal cultures that value interdependence, intense displays of potentially disruptive emotions are infrequent.

 

The Effects of Facial Expressions

Expressions do more than communicate emotion. They also amplify the felt emotion and signal the body to respond accordingly. Emotions, then, arise from the interplay of cognition, physiology, and expressive behaviors.

 

Experienced Emotion

 

Among various human emotions, we looked closely at how we experience three: fear, anger, and happiness.

 

Fear

Fear is an adaptive emotion, but it can be traumatic. Although we seem biologically predisposed to acquire some fears, what we learn through experience and observation best explains the variety of human fears.

 

Anger

Anger is most often evoked by events that not only are frustrating or insulting but also are interpreted as willful, unjustified, and avoidable. Blowing off steam may be temporarily calming, but in the long run it does not reduce anger. Expressing anger can actually make us angrier.

 

Happiness

A good mood boosts people’s perceptions of the world and their willingness to help others. The moods triggered by the day’s good or bad events seldom last beyond that day. Even significant good events, such as a substantial rise in income, seldom increase happiness for long. We can explain the relativity of happiness with the adaptation-level phenomenon and the relative deprivation principle. Nevertheless, some people are usually happier than others, and researchers have identified factors that predict such happiness.

 

Perspectives on Motivation

 

Motivation is the energizing and directing of behavior, the force behind our yearning for food, our longing for sexual intimacy, our need to belong, and our desire to achieve.

 

Instincts and Evolutionary Psychology

Under Darwin’s influence, early theorists viewed behavior as controlled by biological forces, such as specific instincts. When it became clear that people were naming, not explaining, various behaviors by calling them instincts, this approach fell into disfavor. The underlying idea—that genes predispose species-typical behavior—is, however, still influential in evolutionary psychology.

 

Drives and Incentives

Drive reduction theory states that most physiological needs create aroused psychological states, driving us to reduce or satisfy those needs. The aim of drive reduction is internal stability, or homeostasis. Thus, drive reduction motivates survival behaviors, such as eating and drinking. Not only are we pushed by our internal drives, we are also pulled by external incentives. Depending on our personal experiences, some stimuli (for example, certain foods) will arouse our desires.

 

Optimum Arousal

Rather than reducing a physiological need or tension state, some motivated behaviors increase arousal. Curiosity-driven behaviors, for example, suggest that too little as well as too much stimulation can motivate people to seek an optimum level of arousal.

 

A Hierarchy of Motives

Maslow’s hierarchy of needs expresses the idea that, until satisfied, some motives are more compelling than others. It indicates that physiological needs must first be met, then safety, followed by the need for belongingness and love, and finally, esteem needs. Once all of these are met, a person is motivated to meet the need for self-actualization. This order of needs is not universally fixed but it provides a framework for thinking about motivation. 

 

Hunger

 

The Physiology of Hunger

Hunger’s inner push primarily originates not from the stomach’s contractions but from variations in body chemistry, including hormones that heighten or reduce hunger. For example, we are likely to feel hungry when our glucose levels are low or when ghrelin is secreted by an empty stomach. This information is integrated by the hypothalamus, which regulates the body’s weight as it influences our feelings of hunger and satiety. To maintain weight, the body also adjusts its metabolic rate of energy expenditure.

 

The Psychology of Hunger

Our preferences for certain tastes are partly genetic and universal, but also partly learned in a cultural context. The impact of psychological factors, such as challenging family settings and weight-obsessed societal pressures, on eating behavior is dramatic in people with anorexia nervosa, who keep themselves on near-starvation rations, and in those with bulimia nervosa, who binge and purge in secret. In the past half-century a dramatic increase in poor body image has coincided with a rise in eating disorders among women in Western cultures. In addition to cultural pressures, low self-esteem and negative emotions (with a possible genetic component) seem to interact with stressful life experiences to produce anorexia and bulimia.

 

Sexual Motivation

 

The Physiology of Sex

Physiologically, the human sexual response cycle normally follows a pattern of excitement, plateau, orgasm, and resolution, followed in males by a refractory period, during which renewed arousal and orgasm are impossible. Sex hormones, in combination with the hypothalamus, help our bodies develop and function as either male or female. In nonhuman animals, hormones also help stimulate sexual activity. In humans, they influence sexual behavior more loosely, especially once sufficient hormone levels are present.

 

The Psychology of Sex

External stimuli can trigger sexual arousal in both men and women. Sexually explicit materials may also lead people to perceive their partners as comparatively less appealing and to devalue their relationships. In combination with the internal hormonal push and the external pull of sexual stimuli, fantasies (imagined stimuli) influence sexual arousal. Sexual disorders, such as premature ejaculation and female orgasmic disorder, are being successfully treated by new methods, which assume that people learn and can modify their sexual responses.

 

Adolescent Sexuality

Adolescents’ physical maturation fosters a sexual dimension to their emerging identity. But culture is a big influence, too, as is apparent from varying rates of teen intercourse and pregnancy. A near-epidemic of sexually transmitted infections has triggered new research and educational programs pertinent to adolescent sexuality.

 

Sexual Orientation

One’s heterosexual or homosexual orientation seems neither willfully chosen nor willfully changed. Preliminary new evidence links sexual orientation with genetic influences, prenatal hormones, and certain brain structures. The increasing public perception that sexual orientation is biologically influenced is associated with increasing acceptance of gays and lesbians and their relationships.

 

Sex and Human Values

Sex research and education are not value-free. Some say that sex-related values should therefore be openly acknowledged, recognizing the emotional significance of sexual expression. Human sexuality at its life-uniting and love-renewing best affirms our deep need to belong.

 

The Need to Belong

 

No one is an island; we are all, as John Donne noted in 1624, part of the human continent. Our need to affiliate—to feel connected and identified with others—boosted our ancestors’ chances for survival and is therefore part of our human nature. We experience our need to belong when suffering the breaking of social bonds, when feeling the gloom of loneliness or the joy of love, and when seeking social acceptance. For people experiencing ostracism, stress and depression can result. On the other hand, people who feel a sense of belongingness are happier and healthier. 

Notion “emotions”

Emotions are aspect of higher nervous activity that characterize subjective attitude of person to various stimuli arousal in surroundings. Emotional status reflects actual needs of man and helps in its realization.

Classification of emotions

According to subjective status there are positive and negative emotions. Negative emotions are sthenic (aggression, affect) that stimulate human activity and asthenia (horror, sadness, depression) that inhibit behaviour. Lower or elementary emotions are caused by organic needs of man or animal as hanger, thirst and survival, so on). In humans even lover emotions undergo to cortical control and are brining up. Social, historical and cultural customs cause also formation of higher emotions that regulates public and private relations in society. Higher emotions appear due to consciousness and may inhibit lower emotions.

Appearance of emotions in ontogenesis.

In newborns emotions of horror, anger, pleasure, are revealed just after birth. Hunger, pain, getting cool, wet bedclothes cause in newborn child negative emotions with grimace of suffering and crying. Sudden new sound or loss equilibrium causes horror and loss of free movement causes anger. Final formation of human emotions develops gradually with maturation of nervous and endocrine regulatory systems and needs up brining.

Biological importance of emotions

Emotions are important element of human behaviour, creation of conditioned reflexes and mentation. Negative emotions give fusty evaluation of current situation does it useful or not. Mobilizing of efforts helps then to satisfy current needs of person. Positive emotions help to put in memory scheme of behaviour, which was useful and have lead to success.

Animal experiments have shown that a sensory experience causing neither reward nor punishment is remembered hardly at all. Electrical recordings from the brain show that newly experienced types of sensory stimuli almost always excite wide areas in the cerebral cortex. But repetition of the stimulus over and over leads to almost complete excitation of the cortical response, if the sensory experience does not elicit a sense or either reward or punishment. That is, the animal becomes habituated to the sensory stimulus and thereafter ignores it.  If the stimulus causes either reward or punishment rather then indifference, the cortical response becomes progressively more and more intense during repeated stimulation, and the response is said to be reinforced. An animal builds up strong memory traces for sensation that are either rewarding or punishing but, conversely, develops complete habituation to indifferent sensory stimuli.

External manifestations of emotions are revealed in motor acts, effects of autonomic and endocrine regulation. Motor manifestations of emotions are mimic, gesticulation, body posture and walk. Emotional excitation usually is followed by autonomic reactions as blush, dilation of pupils; increase of arterial pressure, rate of heartbeat and breathing. Level of catecholamines in blood and 17-oxycetosteroides in urine rises also. Positive emotion may activate parasympathetic division of autonomic nervous system. Severe emotional excitation may result in visceral disorders because of circulatory disturbances and excess hormones in blood.

Nerve substrate of emotions

Several limbic structures are particularly concerned with the affective nature of sensory sensations – that is whether the sensations are pleasant or unpleasant. The major rew3ard centres have been found to be located along the course of the medial forebrain bundle, especially in the lateral and ventromedial nuclei of the hypothalamus. Less potent reward centres are found in the septum, amygdala, certain areas of the thalamus, basal ganglia, and extending downward into the basal tegmentum of the mesencephalon. The most potent areas for punishment and escape tendencies have been found in the central grey area surrounding the aqueduct of Sylvius in the mesencephalon and extending upward into the periventricular zones of the hypothalamus and thalamus. Less potent punishment areas are found in some locations in the amygdala and the hippocampus. Electrical recording from the brain show that newly experienced types of sensory stimuli almost excite areas in the cerebral cortex.

Theories of emotions

Biological theory of emotions (P.K. Anochkin) considers that life course includes two main stages of behavioural act: 1) formation of needs and motivations that results from negative emotions and 2) satisfaction of needs that leads to positive emotions it case of complete accordance of image and result of action. Incomplete compliance of suspected and real result of action cause negative emotions and continues behavioural act.

Information theory of emotions  (P.V. Simonov)considers that emotions reflect strength human of need and possibility of its satisfaction in current moment. In absence of needs emotions can’t arise. There is also not emotional excitation, if getting excess information about mode of satisfaction this need. Lac of information already causes negative emotions that help to recall to mind life experience and to gather information about current situation.

Neurotransmission of emotional excitation

Emotional excitation is spread in the brain due to variety of neurotransmitters (noradrenalin, acetylcholine, serotonin, dopamine and neuropeptides including opioides. Positive emotions may be explained by revealing catecholamines and negative emotions, aggression result from production acetylcholine in the brain. Serotonin inhibits both kinds of emotions. Decrease of serotonin in blood is followed by groundless anxiety and inhibition of noradrenergic transmission results in sadness.

Structure of behavioural act

According to theory of functional systems (Anochkin) there are such stages of behavioural act: 1) afferent synthesis; 2) taking of decision; 3) acceptor of result of action; 4) efferent synthesis (or programming of action); 5) performing of action; 6) evaluation of final result of action. Due to converging and processing of both sensory information and memory traces afferent synthesis in the brain is performed. Taking of decision is based on afferent synthesis by choosing optimal variant of action.

Neuronal mechanisms of behaviour.

In the very lowest animals olfactory cortex plays essential roles in determining whether the animal eats a particular food, whether the smell of a particular object suggest danger, and whether the odour is sexually inviting, thus making decisions that are of life-or-death importance. The hippocampus originated as part of olfactory cortex. Very early in the evolutionary development of the brain, the hippocampus presumably becomes a critical decision-making neuronal mechanism, determining the importance of the incoming sensory signals. Once this critical decision-making capability had been established, presumably the remainder of the brain began to call on it for the same decision making. Therefore, if the hippocampus says that a neuronal signal is important, the information is likely to be committed to memory. Thus, a person rapidly become habituated to indifferent stimuli but learns assiduously any sensory experience that causes either pleasure or pain. It has been suggested that hippocampus provides the drive that causes translation of short-term memory into long-term memory.

Motivation at Work

 

For most people, work is a huge part of life. At its best, when work puts us in "flow," work can be satisfying and enriching. What, then, enables worker motivation, productivity, and satisfaction? I/O psychology studies behavior in the workplace through its primary subfields: personnel psychology, organizational psychology, and human factors psychology.

 

Personnel Psychology/Harnessing Strengths

Personnel psychologists aim to identify people’s strengths and to match them with organizational tasks. Subjective interviews lead to quickly formed impressions, but they also frequently foster an illusory overconfidence in one’s ability to predict employee success. Structured interviews, pinpointing job-relevant strengths, enhance interview reliability and validity. Personnel psychologists also assist organizations in appraisal that boosts organizations, motivates individuals, and is welcomed as fair.

 

Organizational Psychology: Motivating Achievement

People who excel are often self-disciplined individuals with strong achievement motivation. To motivate employees to achieve, smart managers aim to create an engaged, committed, satisfied workforce. Effective leaders build on people’s strengths, work with them to set specific and challenging goals, and adapt their leadership style to their situation.

 

Common Properties of Psychoactive Drugs

Addiction is a broad term that refers to a condition in which a person feels psychologically and physically compelled to take a specific drug. People experience physical dependence when their body and brain chemistry have physically adapted to a drug. Many physically addictive drugs gradually produce drug tolerance, which means that increasing amounts of the drug are needed to gain the original, desired effect.

For people who are physically dependent on a drug, abstaining from the drug produces withdrawal symptoms. Withdrawal symptoms are unpleasant physical reactions to the lack of the drug, plus an intense craving for it. Withdrawal symptoms are alleviated by taking the drug again. Often, the withdrawal symptoms are opposite to the drug’s action, a phenomenon called the drug rebound effect.

For example, withdrawing from stimulating drugs, like the caffeine in coffee, may produce depression and fatigue. Withdrawal from depressant drugs, such as alcohol, may produce excitability. Each psychoactive drug has a distinct biological effect. Psychoactive drugs may influence many different bodily systems, but their consciousness-altering effects are primarily due to their effect on the brain. Typically, these drugs influence brain activity by altering synaptic transmission among neurons. Drugs affect synaptic transmission by increasing or decreasing neurotransmitter amounts or by blocking, mimicking, or influencing a particular neurotransmitter’s effects (see p. 00). The biological effects of a given drug vary somewhat from one person to another. The person’s weight, gender, and age may influence the intensity of the drug’s effects.Whether the drug is taken on a full or empty stomach or in combination with other drugs also plays a role. Racial and ethnic differences may affect how a drug is metabolized. For example, African-Americans seem to absorb more nicotine from cigarettes than do European-Americans or Mexican-Americans, and they metabolize the nicotine more slowly (Caraballo & others, 1998; Pérez-Stable & others, 1998).

Psychological and environmental factors can also influence the effects of a drug. The response to a drug can be significantly affected by personality characteristics, mood, expectations, experience with the drug, and by the setting in which the drug is taken (Marlatt & others, 1988; Stacy & others, 1990). Why do people abuse drugs? There is no easy answer to that question. It’s difficult to draw a hard-and-fast line between drug use and drug abuse, especially when the drug in question is legal, such as alcohol. Most people would not consider having a cold beer or two at a summer picnic an instance of drug abuse. Chug-alugging a six-pack, however, is a different matter. In contrast to drug use, drug abuse refers to recurrent drug use that results in the disruption of academic, social, or occupational functioning, or in legal or psychological problems (American Psychiatric Association, 2000a). Some authorities widen the definition of drug abuse to refer to any form of drug taking that results in harmful effects. Many factors influence what is considered drug abuse. For example, determining what level of alcohol use constitutes “abuse” varies from one culture to another (Tanaka-Matsumi & Draguns, 1997). Even in the United States, different ethnic groups have very different norms regarding the use of alcohol. Jewish-, Italian-, Greek-, and Chinese-Americans have a tradition of moderate drinking. Drinking alcohol may be restricted to particular social occasions, such as weddings and othe formal celebrations. Some U.S. religious groups, such as the Mormons, Amish, and Muslims, forbid drinking alcohol under any circumstances. Asian-Americans and African-Americans have the lowest rates of alcohol use (Substance Abuse and Mental Health Services Administration, 2002). In the United States, the media stereotype is that drug abuse occurs largely among members of minorities. However, national surveys have consistently shown that a much higher percentage of white teenagers than African-American or other minority teenagers use illegal drugs (Substance Abuse and Mental Health Services Administration, 1994).

 

The Depressants

Alcohol, Barbiturates, and Tranquilizers

 

The depressants are a class of drugs that depress or inhibit central nervous system activity. In general, depressants produce drowsiness, sedation, or sleep. Depressants also relieve anxiety and lower inhibitions. All depressant drugs are potentially physically addictive. Further, the effects of depressant drugs are additive, meaning that the sedative effects are increased when depressants are combined.

Alcohol

A staple of the human diet for thousands of years, alcoholic beverages provide a good example of the potential for a psychoactive drug to be misused (Vallee, 1998). Used in small amounts, alcohol reduces tension and anxiety. Evidence exists that light drinking reduces the risk of heart disease, probably because of its beneficial effects on cholesterol levels.Weddings, parties, and other social gatherings often include alcohol, a tribute to its relaxing and social lubricating properties. But even though alcohol is a legal and readily available drug for adults, it’s also a dangerous drug with a high potential for abuse. Consider these facts:

Many drug experts believe that alcohol abuse has the highest social cost of all drug addictions.

·  Alcohol is involved in at least 50 percent of all homicides, assaults, and highway fatalities (American Psychiatric Association, 2000a; Caetano & others, 2001).

·  Approximately two-thirds of all cases of spousal abuse and violent child abuse involves alcohol use (Steele & Josephs, 1990).

·  Drinking by pregnant women is the leading cause of birth defects and mental retardation—and the only preventable one (National Organization on Fetal Alcohol Syndrome, 2002).

More than half of all Americans who are old enough to drink legally do so at least occasionally. An estimated 14 million Americans have serious alcohol problems. They drink excessively on a regular basis and suffer social, occupational, and health problems as a result of their drinking (Rosenberg, 1993). How many Americans are alcoholic—that is, physically addicted to alcohol? Estimates vary, but a recent survey conducted by the Substance Abuse and Mental Health Services Administration (2002) found that some 11 million people aged 12 and older were dependent upon or abused alcohol. Another 2 million people abused alcohol and one or more illegal drugs.

How Does Alcohol Affect the Body? Generally, it takes about one hour to metabolize the alcohol in one drink, which is defined as 1 ounce of 80-proof whiskey, 4 ounces of wine, or 12 ounces of beer. All three drinks contain the same amount of alcohol; the alcohol is simply more diluted in beer than in hard liquor. Factors such as body weight, gender, food consumption, and the rate of alcohol consumption also affect blood alcohol levels. A slender person who quickly consumes three drinks on an empty stomach will become more than twice as intoxicated as a heavier person who consumes three drinks with food. Women metabolize alcohol more slowly than do men. If a man and a woman of equal weight consume the same number of drinks, the woman will become more intoxicated. Alcohol depresses the activity of neurons throughout the brain. Alcohol impairs cognitive abilities, such as concentration, memory, and speech, and physical abilities, such as muscle coordination and balance. As blood levels of alcohol rise, more brain activity is impaired, until the person loses consciousness. If blood alcohol levels continue to rise, death can occur, because the brain’s respiratory center can no longer function. For this reason, drinking contests are potentially lethal. Binge drinking is a particularly risky practice. Binge drinking is defined as five or more drinks in a row for men, or four or more drinks in a row for women. Every year, several college students die of alcohol poisoning after ingesting large amounts of liquor in a short amount of time. Less well publicized are the other negative effects associated with binge drinking, including aggressive behavior, sexual assault, accidents, and property damage (Hingson & others, 2002; Wechsler & others, 2002). A national survey of college students at 119 colleges found that close to 50 percent of all male students and 40 percent of all female students were binge drinkers (Wechsler & others, 2002). White students were most likely to bingedrink, while African-American students were least likely. While close to half of dormitory residents binged at least occasionally, more than 75 percent of fraternity and sorority house residents were binge drinkers. Table 4.5 shows the behavioural and physical effects of blood alcohol levels.

Because alcohol is physically addictive, the person with alcoholism who stops drinking may suffer from physical withdrawal symptoms. Alcohol withdrawal causes rebound hyperexcitability in the brain. The severity of the withdrawal symptoms depends on the level of physical dependence (Schuckit & others, 1998).With a low level of dependence, withdrawal may involve disrupted sleep, anxiety, and mild tremors (“the shakes”). At higher levels of physical dependence on alcohol, withdrawal may involve confusion, hallucinations, and severe tremors or seizures. Collectively, these severe symptoms are sometimes called delirium tremens, or the DTs. In cases of extreme physical dependence, withdrawal can cause seizures, convulsions, and even death in the absence of medical supervision (O’Brien, 1997).

 

What Are Alcohol’s Psychological Effects? People are often surprised that alcohol is classified as a depressant. Initially, alcohol produces a mild euphoria, talkativeness, and feelings of good humor and friendliness, leading many people to think of alcohol as a stimulant. But these subjective experiences occur because alcohol lessens inhibitions by depressing the brain centers responsible for judgment and self-control. Reduced inhibitions and self-control contribute to the aggressive and violent behavior sometimes associated with alcohol abuse. But the loss of inhibitions affects individuals differently, depending on their environment and expectations regarding alcohol’s effects (Bushman, 1993).

Barbiturates and Tranquilizers

Barbiturates are powerful depressant drugs that reduce anxiety and promote sleep, which is why they are sometimes called “downers.” Barbiturates depress activity in the brain centers that control arousal, wakefulness, and alertness. They also depress the brain’s respiratory centers. Like alcohol, barbiturates at low doses cause relaxation, mild euphoria, and reduced inhibitions. Larger doses produce a loss of coordination, impaired mental functioning, and depression. High doses can produce unconsciousness, coma, and death. Barbiturates produce a very deep but abnormal sleep in which REM sleep is greatly reduced. Because of the additive effect of depressants, barbiturates combined with alcohol are particularly dangerous.

Common barbiturates include the prescription sedatives Seconal and Nembutal. The illegal drug methaqualone (street name quaalude) is almost identical chemically to barbiturates and has similar effects. Barbiturates produce both physical and psychological dependence. Withdrawal from low doses of barbiturates produces irritability and REM rebound nightmares. Withdrawal from high doses of barbiturates can produce hallucinations, disorientation, restlessness, and life-threatening convulsions.

Tranquilizers are depressants that relieve anxiety. Commonly prescribed tranquilizers include Xanax, Valium, Librium, and Ativan. Chemically different from barbiturates, tranquilizers produce similar, although less powerful, effects.

The Opiates

From Poppies to Demerol

Often called narcotics, the opiates are a group of addictive drugs that relieve pain and produce feelings of euphoria. Natural opiates include opium, which is derived from the opium poppy; morphine, the active ingredient in opium; and codeine, which can be derived from either opium or morphine. Synthetic and semisynthetic opiates include heroin, methadone, and the prescription painkillers Oxycontin, Percodan, and Demerol. Opiates produce their powerful effects by mimicking the brain’s own natural painkillers, called endorphins. Opiates occupy endorphin receptor sites in the brain. The word endorphin literally means “the morphine within.” When used medically, opiates alter an individual’s reaction to pain, not by acting at the pain site but by reducing the brain’s perception of pain. Many people recovering from surgery experience a wave of pain relief after receiving narcotics such as morphine, Demerol, or Percodan. People who take opiates in such circumstances rarely develop drug tolerance or dependence (Jacox & others, 1994).

The most frequently used opiate is heroin. When injected into a vein, heroin reaches the brain in seconds, creating an intense rush of euphoria that is followed by feelings of contentment, peacefulness, and warmth.Withdrawing from heroin is not life-threatening, but it does produce unpleasant drug rebound symptoms (O’Brien, 1997). Withdrawal symptoms include an intense craving for heroin, fever, chills, muscle cramps, and gastrointestinal problems.

The Stimulants

Caffeine, Nicotine, Amphetamines, and Cocaine

Stimulants vary in the strength of their effects, legal status, and the manner in which they are taken. All stimulant drugs, however, are at least mildly addicting, and all tend to increase brain activity.We’ll first look at the most widely used and legal stimulants, caffeine and nicotine. Then we’ll examine much more potent stimulants, cocaine and the amphetamines.

Caffeine and Nicotine

Caffeine is found in coffee, tea, cola drinks, chocolate, and many over-the-counter medications (see Table 4.6). Most Americans consume caffeine in some form every day (DeAngelis, 1994b). In fact, caffeine is the most widely used psychoactive drug in the world.

Caffeine stimulates the cerebral cortex in the brain, resulting in an increase in mental alertness and wakefulness. Even a single cup of coffee has a noticeable effect on the cerebral cortex. Yes, coffee drinkers, caffeine is physically addictive. Regular coffee, tea, or cola drinkers will experience withdrawal symptoms if they abruptly stop their caffeine intake. Headaches, irritability, drowsiness, and fatigue may last up to a week. Even just a few hours of caffeine deprivation can produce noticeable withdrawal symptoms of sleepiness and fatigue (Phillips-Bute & Lane, 1997). At high doses, caffeine can produce anxiety, restlessness, insomnia, and increased heart rate—symptoms that are collectively called “coffee nerves.” When Mike, in the Prologue, lit up a cigarette, he did so under the mistaken impression that smoking would help him relax and fall asleep. But cigarettes contain nicotine, an extremely addictive stimulant. Nicotine is found in all tobacco products, including pipe tobacco, cigars, cigarettes, and smokeless tobacco. About 25 percent of American adults use tobacco regularly. The proportion of smokers is much higher in Japan, many European countries, and developing countries (Bartecchi

& others, 1995). Like coffee, nicotine increases mental alertness and reduces fatigue or drowsiness. Functional

MRI scans show that nicotine increases neural activity in many areas of the brain, including the frontal lobes, thalamus, hippocampus, and amygdala (Stein & others, 1998). Thus, it’s not surprising that smokers report that tobacco enhances mood, attention, arousal, and vigilance. When cigarette smoke is inhaled, nicotine reaches the brain in seconds. But within 30 minutes or so, nicotine has left the brain. Thus, the addicted pack-a-day smoker will light a cigarette every 30 to 40 minutes to maintain a relatively constant nicotine level in the brain. Over the course of a year, that averages out to 70,000 “hits” of nicotine. Nicotine is highly addictive, both physically and psychologically. People who start smoking for nicotine’s stimulating properties often continue smoking to avoid the withdrawal symptoms. Along with an intense craving for cigarettes, withdrawal symptoms include jumpiness, irritability, tremors, headaches, drowsiness, “brain fog,” and lightheadedness (Shiffman & others, 1995).

Amphetamines and Cocaine

Like caffeine and nicotine, amphetamines and cocaine are addictive substances that stimulate brain activity, increasing mental alertness and reducing fatigue. However, amphetamines and cocaine also elevate mood and produce a sense of euphoria. When abused, both drugs can produce severe psychological and physical problems. Sometimes called “speed” or “uppers,” amphetamines suppress appetite and were once widely prescribed as diet pills. Tolerance to the appetite-suppressant effects occurs quickly, so progressive increases in amphetamine dosage are required to maintain the effect. Consequently, amphetamines are rarely prescribed today for weight control.

Using any type of amphetamines for an extended period of time is followed by “crashing”—withdrawal symptoms of fatigue, deep sleep, intense mental depression, and increased appetite. This is another example of a drug rebound effect. Users also become psychologically dependent on the drug for the euphoric state, or “rush,” that it produces, especially when injected. Benzedrine and dexedrine are prescription amphetamines. Methamphetamine, also known as meth, is an illegal drug that can be easily manufactured in home or street laboratories. Providing an intense high that is longer-lasting and less expensive than cocaine, meth usage has spread from the western United States to the rest of the country, including small towns in the rural Midwest and South. As the popularity of methamphetamine has increased, so have concerns about the drug’s long-term effects. PET scans of former methamphetamine users have shown abnormalities in brain structure and functioning (Volkow & others, 2001a, 2001b, 2001c). Even after several months of abstinence, the brains of former meth users showed a significant reduction in the number of dopamine receptors and transporters (see Figure 4.6). Dopamine transporters help transport “used” dopamine back into the neurons that produce it. Some former methamphetamine users had lost up to 24 percent of the normal level of dopamine transporters. Memory and motor skill problems were common in the former abusers and were most severe in those with the greatest loss of dopamine transporters. Cocaine is an illegal stimulant derived from the leaves of the coca tree, which is found in South America. (The coca plant is not the source of cocoa or chocolate, which is made from the beans of the cacao plant.) When inhaled, or “snorted,” in purified, powdered form, cocaine reaches the brain within a few minutes. Inhaling cocaine produces intense euphoria, mental alertness, and self-confidence, which lasts for several minutes.

 

A more concentrated form of cocaine, called crack, is smoked rather than inhaled. Prolonged use of amphetamines or cocaine can result in stimulant-induced psychosis, also called amphetamine psychosis or cocaine psychosis. Schizophrenialike symptoms develop, including auditory hallucinations of voices and bizarrely paranoid ideas.

Psychedelic Drugs

Mescaline, LSD, and Marijuana

The term psychedelic drug was coined in the 1950s to describe a group of drugs that create profound perceptual distortions, alter mood, and affect thinking. Psychedelic literally means “mind manifesting” (Tart, 1990).

Mescaline and LSD

Naturally occurring psychedelic drugs have been used for thousands of years. Mescaline, which is derived from the peyote cactus, has been used for centuries in the religious ceremonies of Mexican Indians. Another psychedelic drug, called psilocybin, is derived from Psilocybe mushrooms, sometimes called magic mushrooms. Psilocybin has been used since 500 B.C. in religious rites in Mexico and Central America.

In contrast to these naturally occurring psychedelics, LSD (lysergic acid diethylamide) is a powerful psychedelic drug that was first synthesized in the late 1930s. LSD is far more potent than mescaline or psilocybin. Just 25 micrograms, or one-millionth of an ounce, of LSD can produce profound psychological effects with relatively few physiological changes. LSD and psilocybin are very similar chemically to the neurotransmitter serotonin, which is involved in regulating moods and sensations. LSD and psilocybin mimic serotonin in the brain, stimulating serotonin receptor sites (Aghajanian, 1994). The effects of a psychedelic experience vary greatly, depending on an individual’s personality, current emotional state, surroundings, and the other people present. A “bad trip” can produce extreme anxiety, panic, and even psychotic episodes. Tolerance to psychedelic drugs may occur after heavy use. However, even heavy users of LSD do not develop physical dependence, nor do they experience withdrawal symptoms if the drug is not taken. Adverse reactions to LSD include flashbacks (recurrences of the drug’s effects), depression, long-term psychological instability, and prolonged psychotic reactions (Smith & Seymour, 1994). In a psychologically unstable or susceptible person, even a single dose of LSD can precipitate a severe psychotic reaction.

Marijuana

The common hemp plant, Cannabis sativa, is used to make rope and cloth. But when its leaves, stems, flowers, and seeds are dried and crushed, the mixture is called marijuana, one of the most widely used illegal drugs. Marijuana’s active ingredient is the chemical tetrahydrocannabinol, abbreviated THC. When marijuana is smoked, THC reaches the brain in less than 30 seconds. One potent form of marijuana, ha shish, is made from the resin of the hemp plant. Hashish is sometimes eaten. To lump marijuana with the highly psychedelic drugs mescaline and LSD is somewhat misleading. At high doses, marijuana can sometimes produce sensory distortions that resemble a mild psychedelic experience. Low-to-moderate doses of THC typically produce a sense of well-being, mild euphoria, and a dreamy state of relaxation. Senses become more focused and sensations more vivid. Taste, touch, and smell may be enhanced; time perception may be altered. A little more than a decade ago, researchers discovered receptor sites in the brain that are specific for THC. They’ve also discovered a naturally occurring brain chemical, called anandamide, that is structurally similar to THC and that binds to the THC receptors in the brain (Devane & others, 1992). Anandamide appears to be involved in regulating the transmission of pain signals and may reduce painful sensations (Calignano & others, 1998;Walker & others, 1999). Researchers also suspect that anandamide may be involved in mood and memory.

There are very few THC receptors in the brainstem, the part of the brain that controls such life support functions as breathing and heartbeat. Thus, high doses of THC do not interfere with respiratory and cardiac functions as depressants and opiates do.

Most marijuana users do not develop tolerance or physical dependence. Chronic users of extremely high doses can develop some tolerance to THC and may experience withdrawal symptoms when its use is discontinued (de Fonseca & others, 1997). Such symptoms include irritability, restlessness, insomnia, tremors, and decreased appetite. Marijuana and its active ingredient, THC, have been shown to be helpful in the treatment of pain, epilepsy, hypertension, nausea, glaucoma, and asthma (Snyder, 1990). In cancer patients, THC can prevent the nausea and vomiting caused by chemotherapy. However, the medical use of marijuana is limited and politically controversial. On the negative side, marijuana interferes with muscle coordination and perception and may impair driving ability. When marijuana and alcohol use are combined, marijuana’s effects are intensified—a dangerous combination for drivers. Marijuana has also been shown to interfere with learning, memory, and cognitive functioning (Pope & others, 2001).

Designer “Club” Drugs

Ecstasy and the Dissociative Anesthetic Drugs

Some drugs don’t fit into neat categories. The “club drugs” are a loose collection of psychoactive drugs that are popular at dance clubs, parties, and the all-night dance parties called “raves.” Many of these drugs are designer drugs, meaning that they were synthesized in a laboratory rather than derived from naturally occurring compounds. In this section, we’ll take a look at three of the most popular club drugs—ecstasy, ketamine, and PCP.

The initials MDMA stand for the long chemical name of the quintessential club drug better known as ecstasy. Other street names are X, XTC, Adam, and the “love drug.” Ecstasy was developed by a German pharmaceutical company in 1912 for possible use as an appetite suppressant, but it was not tested on humans until the 1970s. Structurally similar to both mescaline and amphetamine,MDMA has stimulant and psychedelic effects. While the use of other illegal drugs has remained stable or declined over the past decade, the use of ecstasy has sharply increased in western Europe and the United States (Zickler, 2001). At low doses, MDMA acts as a stimulant, but at high doses it has mild psychedelic effects. Its popularity, however, results from its emotional effects: Feelings of euphoria and increased well-being are common. People who have taken ecstasy also say that the drug makes them feel loving, open, and closer to others—effects that led to its use in psychotherapy for a brief time until its adverse effects became apparent (Braun, 2001). Ecstasy’s side effects hint at the problems that can be associated with its use: dehydration, rapid heartbeat, tremors, muscle tension and involuntary teeth-clenching, and hyperthermia (abnormally high body temperature). Rave party-goers who take MDMA in crowded, hot surroundings are particularly at risk for collapse or death from dehydration and hyperthermia.

 

The “love drug” effects of ecstasy may result from its unique effect on serotonin in the brain. Along with causing neurons to release serotonin, MDMA also blocks serotonin reuptake, amplifying and prolonging serotonin effects (Braun, 2001). While flooding the brain with serotonin may temporarily enhance feelings of emotional well-being, there are adverse trade-offs. First, the “high” of ecstasy is often followed by depression when the drug wears off. More ominously, animal studies have shown that moderate or heavy use of ecstasy can lead to long-term, potentially irreversible damage to serotonin nerve endings in the brain (Ricaurte & others, 1998). Several studies have shown similar damage to serotonin neurons in the human brain (Croft & others, 2001; Reneman & others, 2001a). Female users may be more susceptible to brain damage than male users (see Figure 4.7).

Other studies have shown that serotonin levels become severely depleted after long-term use, possibly causing the depression that follows when the drug wears off (Kuhn & Wilson, 2001). Equally troubling are cognitive effects: In one study, memory and verbal reasoning problems persisted up to a year after the last dose was taken (Reneman & others, 2001b). Another class of drugs that make their appearance at dance clubs and raves are the dissociative anesthetics, including phencyclidine, better known as PCP or angel dust, and ketamine (street name Special K). Originally developed to serve as general anesthetics for surgery in the late 1950s, both PCP and ketamine deaden pain and, at high doses, can induce a stupor or coma. Because of their psychological effects, these drugs were largely abandoned for general surgical use in humans.

Rather than producing actual hallucinations, PCP and ketamine produce marked feelings of dissociation and depersonalization. Feelings of detachment from reality—including distortions of space, time, and body image—are common. Generally, the effects of PCP are more intense and of a longer duration than those of ketamine.

PCP can be eaten, snorted, or injected, but it is most often smoked or sprinkled on tobacco or marijuana. The effects are unpredictable, and a PCP trip can last for several days. Some users of PCP report feelings of invulnerability and exaggerated strength. PCP users can become severely disoriented, violent, aggressive, or suicidal. High doses of PCP can cause hyperthermia, convulsions, and death. PCP affects levels of the neurotransmitter glutamate, indirectly stimulating the release of dopamine in the brain. Thus, PCP is highly addictive. Memory problems and depression are common effects of long-term use.