Substances and Memory

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Marijuana and memoryDoes alcohol have an effect on academics?

Marijuana and memory

This is a good article explaining that short-term memory deficits can persist for some weeks after stopping marijuana. So, it’s a good idea not to smoke in the weeks before exams.

“It definitely fogs your brain,” says Lambros Messinis of the University Hospital of Patras in Greece, on the effects of marijuana. That, of course, is why people smoke it in the first place. What Messinis claims, however, is that it has a more serious effect: he says that long-term users gradually become worse at learning and remembering things.

Messinis and his colleagues compared the mental abilities of 20 people who had smoked dope at least four times weekly for an average of 15 years with 20 shorter-term users averaging 7 years of use, and 24 controls. None of the subjects had smoked for at least 24 hours before the test, and Messinis used a standard psychological method to control for differences in intelligence before they started using marijuana.

The veteran users performed worst in memory tests: asked to recall lists of 15 words they had seen earlier, for example, they averaged seven, compared with nine for the shorter-term users and 12 for the controls.

(Neurology, vol 66, p 737).

Excerpts taken from

Does alcohol have an effect on academics? YES!

On average, students who drink the most alcohol receive the lowest grades:

  • D and F students average 9.5 drinks per week
  • C students average 5.6 drinks per week
  • B students average 4.4 drinks per week
  • A students average 3.1 drinks per week

Alcohol is estimated to be the cause of 40% of major academic deficiencies and nearly 30% of all dropouts.  Why?

  • People who are out late partying often over-sleep and miss classes.
  • Someone who is hung over is more likely to sleep in, or feels too sick to attend class.
  • People who party several times a week can fall behind on homework, projects or papers.

Evidence suggests that alcohol can also affect some of the brain functions that affect learning.

Memory foundation

The ability to form new memories. A chronic drinker may be able to recall something from their childhood, but may not be able to remember what they ate for lunch a few hours ago. On mental ability tests, chronic drinkers often perform poorly on retention skills.

Abstract thinking

One of the major tasks of the brain is to distinguish the difference between concrete, obvious and surface reasoning and abstract thinking such as word puzzles and interpreting stories. Abstract thinking is more difficult for chronic drinkers.


Problem solving often involves using different strategies and reasoning skills. We also need mental flexibility, the ability to switch strategies and approaches to problems in order to solve them. Often under testing, heavy drinkers find themselves taking a lot longer to find solutions because they get stuck in one particular method of problem solving.

Attention and concentration

There is some evidence that chronic drinkers have a hard time keeping their attention focused and maintaining their concentration. The degree to which these functions are affected depends on how much alcohol is consumed. Chronic long-term abusers of alcohol experience the major effects. However, social drinkers also develop deficits in their mental functioning. The more alcohol a person has when they go out, the more likely the negative effects will develop.

Sourced from: The Bacchus Network