TRIGGERING AN EX-ADDICT'S CRAVING

Focuses on a study which examined the role of association in triggering ex-addicts' cravings for amphetamines. Methodology; Results of the study.

By Kelly McCarthy, published on January 1, 2002 - last reviewed on January 23, 2015

ADDICTION

DRUG USE CAUSES LONG TERM OR PERMANENT CHANGES IN NEURAL
PATHWAYS

AN EX-SMOKER'S GREATEST enemy may not be the cigarette, but the
ashtray. Items like needles or clinking glasses might trigger old drug or
alcohol cravings after years of abstinence. In a study published in the
Journal of Neuroscience, Kent C. Berridge, Ph.D., and Cindy L. Wyvell,
Ph.D., professors of psychology at the University of Michigan, found that
rats conditioned to associate sugar pellets with amphetamines exhibited
cravings for the drugs when exposed to sugar pellets--long after the
amphetamines were out of their system. This leads to speculation that
drug use causes long-term or permanent changes to certain neural
systems.

In the study, rats were trained to seek nonaddictive sugar pellets
by pressing a lever and to associate a tonal sound with the pellets. A
group of rats were then given amphetamine injections, and the experiment
resumed 14 days later, when this group was drug-free. When the rats
pressed the lever in search of the sugar reward, they received the sound
cue intermittently. The amphetamine-sensitized rats pressed the lever 200
times more than did the control group, at a rate similar to that of rats
with amphetamines in their system. Thus, rats on amphetamines and those
sensitized but drug-free reacted equally voraciously to the cue.

No one knows how long such triggers might persist in humans.
Berridge postulates that it can last from at least one year to as much as
half a lifetime. "There's just no data on this yet" he admits.

DRUG USE CAUSES LONG TERM OR PERMANENT CHANGES IN NEURAL
PATHWAYS