178 ChapTER 5 Body Rhythms and Mental States
personality characteristics, and physical tolerance for
the drug. Women generally get drunker than men
on the same amount of alcohol because women are
smaller, on average, and their bodies metabolize
alcohol differently (Fuchs et al., 1995). Asians are
more likely than Anglos to have a genetic variation
that prevents alcohol from being metabolized nor-
mally. As a result, they may have adverse reactions
to even small amounts of alcohol, including severe
headaches, facial flushing, and diarrhea (Cloninger,
1990). For any individual, a drug may have one
effect after a tiring day and a different one after
a rousing quarrel, or the effect may vary with the
time of day because of the body’s circadian rhythms.
And some differences among individuals in their
responses to a drug may be due to their personality
traits. When people who are prone to anger and
irritability wear nicotine patches, dramatic bursts of
activity occur in the brain while they are working
on competitive or aggressive tasks. These changes
do not occur, however, in more relaxed and cheerful
people (Fallon et al., 2004).3
Environmental setting refers to the context in
which a person takes the drug. A person might
have one glass of wine at home alone and feel
sleepy but have three glasses of wine at a party
and feel full of energy. Someone might feel
happy and high drinking with good friends but
fearful and nervous drinking with strangers. In
an early study of reactions to alcohol, most ofsymptoms, which, depending on the drug, may
include nausea, abdominal cramps, sweating, mus-
cle spasms, depression, disturbed sleep, and an
intense craving for more of the drug.The Psychology of Drug Effects
LO 5.13
People often assume that the effects of a drug
are automatic, the inevitable result of the drug’s
chemistry. But reac-
tions to a psychoac-
tive drug involve
more than the drug’s
chemical properties.
They also depend on
a person’s experience
with the drug, individual characteristics, environ-
mental setting, and mental set.1
Experience with the drug refers to the number
of times a person has taken it. When people
use a drug—a cigarette, an alcoholic drink, a
stimulant—for the first time, their reactions vary
markedly, from unpleasant to neutral to enjoyable.
But reactions may become increasingly positive
once a person has used a drug for a while and has
become familiar with its effects.2
Individual characteristics include body weight,
metabolism, initial state of emotional arousal,About Drug EffectsThinking
CriTiCallyAttitudes about drugs vary with the times. Cigarette smoking was once promoted as healthy and glamorous. And
before cocaine was banned in the United States in the 1920s, it was widely touted as a cure for everything from
toothaches to timidity. It was used in teas, tonics, throat lozenges, and even soft drinks (including, briefly, Coca-Cola,
which derived its name from the coca plant).