Above The Propaganda

I forgot, does marijuana cause short-term memory impairment?

The effect of marijuana on memory is its most dramatic
and the easiest to notice. Many inexperienced marijuana
users find that they have very strange, sudden and
unexpected memory lapses. These usually take the form of
completely forgetting what you were talking about when you
were right in the middle of saying something important.
However, these symptoms only occur while a person is `high'.
They do not carry over or become permanent, and examinations
of extremely heavy users has not shown any memory or
thinking problems. More experienced marijuana users seem to
be able to remember about as well as they do when they are
not `high.'

Studies which have claimed to show short-term memory
impairment have not stood up to scrutiny and have not been
duplicated. Newer studies show that marijuana does not
impair simple, real-world memory processes. Marijuana does
slow reaction time slightly, and this effect has sometimes
been misconstrued as a memory problem. To put things in
perspective, one group of researchers made a control group
hold their breath, like marijuana smokers do. Marijuana
itself only produced about twice as many effects on test
scores as breath holding. Many people use marijuana to
study. Other people cannot, for some reason, use marijuana
and do anything that involves deep thought. Nobody knows
what makes the difference.

This article is from the Hemp / Cannabis / Marijuana FAQ, by Brian S. Julin [email protected] with numerous contributions by others.

From Marijuana Myth-Fact
Myth: Marijuana Impairs Memory and Cognition. Under the influence of marijuana, people are unable to think rationally and intelligently. Chronic marijuana use causes permanent mental impairment.

Fact: Marijuana produces immediate, temporary changes in thoughts, perceptions, and information processing. The cognitive process most clearly affected by marijuana is short-term memory. In laboratory studies, subjects under the influence of marijuana have no trouble remembering things they learned previously. However, they display diminished capacity to learn and recall new information. This diminishment only lasts for the duration of the intoxication. There is no convincing evidence that heavy long-term marijuana use permanently impairs memory or other cognitive functions.

Wetzel, C.D. et al., “Remote Memory During Marijuana Intoxication,” Psychopharmacology 76 (1982): 278-81.
Deadwyler, S.A. et al., “The Effects of Delta-9-THC on Mechanisms of Learning and Memory.”Neurobiology of Drug Abuse:  Learning and Memory. Ed. L. Erinoff. Rockville, MD: National Institute on Drug Abuse 1990. 79-83.
Block, R.I. et al., “Acute Effects of Marijuana on Cognition: Relationships to Chronic Effects and Smoking Techniques.” Pharmacology Biochemistry and Behavior 43 (1992): 907-917.



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