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SubstanceRelated Disorders
490 Chapter 12 Psychological Disorders severity of the symptoms may vary (Çeponien et al., 2003; Constantino & Todd, 2003). Estimates of the prevalence of autistic spectrum disorders vary from 10 to 20 children per 10,000 births (Bryson & Smith, 1998; Filipek et al., 1999) to as high as 62 per 10,000 (Chakrabarti & Fombonne, 2001), depending largely on the diagnostic criteria employed (Gernsbacher, Dawson, & Goldsmith, 2005). About half of these children suffer autistic disorder, which can be the most severe disorder of the group. The earliest signs of autistic disorder usually occur within the first thirty months after birth, as these babies show little or no evidence of forming an attachment to their caregivers. Language development is seriously disrupted in most of these children; half of them never learn to speak at all. However, those who display “high functioning autism” or a less severe autistic spectrum disorder called Asperger’s disorder are able to function adaptively and, in some cases, independently as adults (e.g., Grandin, 1996). Possible biological roots of autistic disorder include genetic factors (Segurado et al., 2005; Skaar et al., 2005; Vorstman et al., 2006) or neurodevelopmental abnormalities that affect language and communication (Baron-Cohen, Knickmeyer, & Belmonte, 2005; Belmonte et al., 2004; Courchesne et al., 2001; Grossberg & Seidman, 2006). The more specific causes of autistic disorder remain unknown, but it is likely that genetic influences, along with prenatal damage leading to structural brain abnormalities, are involved (Carper & Courchesne, 2000; Juul-Dam, Townsend, & Courchesne, 2001; Rodier, 2000; Szatmari et al., 1998; Vidal et al., 2006). Researchers today have rejected the once-popular hypothesis that autistic disorder is caused by cold and unresponsive parents. Disorders of childhood differ from adult disorders not only because the patterns of behavior are distinct but also because their early onset disrupts development. To take one example, children whose separation anxiety causes spotty school attendance may not only fall behind academically but also may fail to form the relationships with other children that promote normal social development (Wood, 2006). Some children never make up for this deficit. They may drop out of school and risk a life of poverty, crime, and violence. Moreover, children depend on others to get help for their psychological problems, but all too often those problems may go unrecognized or untreated. For some, the long-term result may be adult forms of mental disorder. Substance-Related Disorders Childhood disorders, especially externalizing disorders, often lead to substance-related disorders in adolescence and adulthood. DSM-IV defines substance-related disorders as the use of psychoactive drugs for months or years in ways that harm the user or others. These disorders create major political, economic, social, and health problems worldwide. The substances involved most often are alcohol and other depressants (such as barbiturates), opiates (such as heroin), stimulants (such as cocaine or amphetamines), and hallucinogens (such as LSD). One effect of using some substances (including alcohol, heroin, and amphetamines) is addiction, a physical need for the substance. DSM-IV calls addiction physiological dependence. Even when the use of a drug does not create physical addiction, some people may overuse, or abuse, it because the drug gives them temporary self-confidence, enjoyment, or relief from tension. DSM-IV defines substance abuse as a pattern of use that causes serious social, legal, or interpersonal problems. In other words, people can become psychologically dependent on psychoactive drugs without becoming physiologically addicted to them. People who are psychologically dependent on a drug often have problems that are at least as serious as those of people who are addicted and that may be even more difficult to treat. In the consciousness chapter, we describe how consciousness is affected by a wide range of psychoactive drugs. Here, we focus more specifically on the problems associated with the use and abuse of alcohol, heroin, and cocaine. substance-related disorders Problems involving the use of psychoactive drugs for months or years in ways that harm the user or others. addiction Development of a physical need for a psychoactive drug. Alcohol Use Disorders In the United States, about 8.4 percent of people over the age of twelve display alcohol dependence or alcohol abuse (Grant et al., 2004). This means that about 19 million individuals engage in a pattern of continuous or off-and-on drinking that may lead to addiction and that almost always causes severe social, physical, and A Sampling of Other Psychological Disorders alcoholism A pattern of continuous or intermittent drinking that may lead to addiction and that almost always causes severe social, physical, and other problems. 491 other problems (e.g., Murphy et al., 2005). Males outnumber females in this category by a ratio of about three to one, although the problem is on the rise among women and among teenagers of both genders (Chassin, Pitts, & Prost, 2002; Grant et al., 2004). Prolonged overuse of alcohol can result in life-threatening liver damage, reduced cognitive abilities, vitamin deficiencies that can lead to severe and permanent memory loss, and a host of other physical ailments (Hommer et al., 2001; Pfefferbaum et al., 2001). Alcohol dependence or abuse, commonly referred to as alcoholism, has been implicated in half of all the traffic fatalities, homicides, and suicides that occur each year (National Institute on Alcohol Abuse and Alcoholism [NIAAA], 2001; Yi, Williams, & Smothers, 2004). Alcoholism also figures prominently in rape and child abuse, as well as in elevated rates of hospitalization and absenteeism from work, resulting in total costs to society of over $184 billion each year (Harwood, Fountain, & Livermore, 1998; NIAAA, 2001). It is estimated that about half of U.S. adults have a close relative who has or had displayed alcoholism and that about 25 percent of children are exposed to adults who display alcohol abuse or dependence (NIAAA, 2001). Children growing up in families in which one or both parents abuse alcohol are at increased risk for developing a host of mental disorders, including substance-related disorders (Hoffmann & Cerbone, 2002). And as described in the chapter on human development, children of mothers who abused alcohol during pregnancy may be born with fetal alcohol syndrome. The biopsychosocial model suggests that alcohol abuse stems from a combination of genetic characteristics (including inherited aspects of temperament such as impulsivity and emotionality) and what people learn in their social and cultural environments (Elkins et al., 2006; Kendler, Jacobson, et al., 2003; Petry, 2001; Sher et al., 1991; Wall et al., 2001). For example, the children of people with alcoholism are more likely than others to develop alcoholism themselves; and if the children are identical twins, both are at increased risk for alcoholism, even when raised apart (Kendler et al., 1992; McGue, 1999; Slutske et al., 1998). It is still unclear just what might be inherited or which genes are involved. One possibility involves inherited abnormalities in the brain’s neurotransmitter systems or in the body’s metabolism of alcohol (Martinez et al., 2005; Nurnberger et al., 2001; Petrakis et al., 2004). Males with alcoholism do tend to be less sensitive than other people to the effects of alcohol—a factor that may contribute to greater consumption (Pollack, 1992; Schuckit, 1998). Now that the human genome has been decoded, researchers are focusing on specific chromosomes as the possible location of genes that predispose people to—or protect them from—the development of alcoholism (Cheng et al., 2004; NIAAA, 2000, 2001; Wall et al., 2005). However, the genetics of addiction is highly complex; there is probably not a single gene for alcoholism (Crabbe, 2002). As with other disorders, many genes interact with each other and with environmental events, including parental influences (Rhee et al., 2003). One study found that, as expected, the sons of identical twins were at elevated risk for alcoholism if their father had alcoholism, but not if it was the father’s identical twin who had alcoholism (Jacob et al., 2003). In these cases, something in the boys’ nonalcoholic family environment had apparently moderated whatever genetic tendency toward alcoholism they might have inherited. Youngsters typically learn to drink by watching their parents and their peers. The observations help shape their expectations, such as that alcohol will make them feel good and help them cope with stressors (Chassin, Pitts, & Prost, 2002; Schell et al., 2005). But alcohol use can become abuse, and perhaps addiction, if drinking is a person’s main coping strategy (NIAAA, 2001). The importance of learning is supported by evidence that alcoholism is more common among ethnic and cultural groups (such as the Irish and English) in which frequent drinking tends to be socially approved than among groups (such as Jews, Italians, and Chinese) in which all but moderate drinking tends to be discouraged (Gray & Nye, 2001; Wilson et al., 1996). Moreover, different forms of social support for drinking can result in different consumption patterns within a cultural group. For example, one study found significantly more drinking among Japanese men living in Japan (where social norms for males’ drinking are most permissive) compared with Japanese men living in Hawaii or California, where excessive drinking is less strongly supported (Kitano et al., 1992).