164 Chapter
5
States of Consciousness
COCAINE
Although its use has declined over the last decade, the stimulant cocaine and its
derivative, crack, still represent a serious concern. Cocaine is inhaled or “snorted”
through the nose, smoked, or injected directly into the bloodstream. It is rapidly
absorbed into the body and takes effect almost immediately.
When used in relatively small quantities, cocaine produces feelings of profound
psychological well-being, increased confi dence, and alertness. Cocaine produces this
“high” through the neurotransmitter dopamine. Dopamine is one of the chemicals
that transmit between neurons messages that are related to ordinary feelings of
pleasure. Normally when dopamine is released, excess amounts of the neurotrans-
mitter are reabsorbed by the releasing neuron. However, when cocaine enters the
brain, it blocks reabsorption of leftover dopamine. As a result, the brain is fl ooded
with dopamine-produced pleasurable sensations (Jarlais, Arasteh, & Perlis, 2007;
Redish, 2004).
However, there is a steep price to be paid for the pleasurable effects of cocaine. The
brain may become permanently rewired, triggering a psychological and physical addic-
tion in which users grow obsessed with obtaining the drug. Over time, users deteriorate
mentally and physically. In extreme cases, cocaine can cause hallucinations—a common
one is of insects crawling over one’s body. Ultimately, an overdose of cocaine can lead
to death (George & Moselhy, 2005; Little et al., 2009; Paulozzi, 2006).
Almost 2.5 million people in the United States are occasional cocaine users, and
as many as 1.8 million people use the drug regularly. Given the strength of cocaine,
withdrawal from the drug is diffi cult. Although the use of cocaine among high school
students has declined in recent years, the drug still represents a major problem (John-
ston et al., 2009).
Depressants: Drug Lows
In contrast to the initial effect of stimulants, which is an increase in arousal of the
central nervous system, the effect of depressants is to impede the nervous system
by causing neurons to fi re more slowly. Small doses result in at least temporary feel-
ings of intoxication —drunkenness—along with a sense of euphoria and joy. When
large amounts are taken, however, speech becomes slurred and muscle control
becomes disjointed, making motion diffi cult. Ultimately, heavy users may lose con-
sciousness entirely.
ALCOHOL
The most common depressant is alcohol, which is used by more people than is any
other drug. Based on liquor sales, the average person over the age of 14 drinks 2½
gallons of pure alcohol over the course of a year. This works out to more than 200
drinks per person. Although alcohol consumption has declined steadily over the
last decade, surveys show that more than three-fourths of college students indicate
that they have had a drink within the last 30 days (Jung, 2002; Midanik, Tam, &
Weisner, 2007).
One of the more disturbing trends is the high frequency of binge drinking among
college students. For men, binge drinking is defi ned as having fi ve or more drinks in
one sitting; for women, who generally weigh less than men and whose bodies absorb
alcohol less effi ciently, binge drinking is defi ned as having four or more drinks at
one sitting (Mokdad, Brewer, & Naimi, 2007).
Around 50% of male college students and 40% of female college students say they
engaged in binge drinking at least once within the previous two weeks (see Figure 5).
Some 17% of female students and 31% of male students admitted drinking on 10 or
more occasions during the previous 30 days. Furthermore, even light drinkers were
affected by the high rate of alcohol use: Two-thirds of lighter drinkers said that they
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