-> No leer: drug, a user has a deficit of the transmitters and enters a withdrawal
state, marked by reduced energy, reduced motivation,
and mild depression.
Stimulant drugs produce varied behavioral effects. Low
doses enhance attention, and low doses of amphetamine are
sometimes used as a treatment for attention deficit disorder
(ADHD), a condition marked by impulsiveness and poor
control of attention. However, higher doses of stimulant drugs
impair attention and learning (Stalnaker et al., 2007). A study
of pairs of human twins, in which one twin abused cocaine or
amphetamine and the other did not, found that the twin abusing
stimulant drugs showed attentional problems that lingered
for a year after quitting the drugs (Toomey et al., 2003).
By altering blood flow, cocaine also increases the risk of stroke
and epilepsy (Strickland, Miller, Kowell, & Stein, 1998).
Methylphenidate (Ritalin), another stimulant drug, is
also prescribed for people with attention-deficit hyperactivity
disorder. Methylphenidate and cocaine block the reuptake of
dopamine in the same way at the same brain receptors. The
differences between the drugs relate to dose and time course.
Cocaine users typically sniff it or inject it to produce a rapid
rush of effect on the brain. People taking methylphenidate
pills experience a gradual increase in the drug’s concentration
over an hour or more, followed by a slow decline. Therefore,
methylphenidate does not produce the sudden rush of excitement
that is common with cocaine. However, someone who
injects methylphenidate experiences effects similar to cocaine’s,
including the risk of addiction.
You might wonder whether the use of methylphenidate in
childhood makes people more likely to abuse drugs later. This
is not an easy question to investigate. Overall, people with
ADHD are more likely than other people to use and abuse
tobacco, alcohol, and many other drugs. The needed comparison
is between people with ADHD who have taken methylphenidate
and those who have not. However, no one can randomly
assign people to these two groups. Those receiving
methylphenidate probably differ from those not receiving it in
several ways. Bearing these difficulties in mind, researchers
have conducted a few studies, and have found inconclusive results.
Some studies suggest that using methylphenidate increases
the risk of later drug abuse, and other studies find that
it decreases the risk (Golden, 2009). Evidently the risk does
not change enormously, one way or the other.
Answers
Stop & C <-
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