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SubstanceRelated Disorders

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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).
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