According to the latest study in JAMA smoking marijuana affects our memory.

(Mirror Daily, United States) – According to the latest study that was published in JAMA journal of Internal Medicine, prolonged use of marijuana affects our memory, especially the short-term kind and the verbal kind.

A professor at the Lausanne University, Reto Auer, was in charge of a team of scientists that examined data gathered from the analysis of approximately 3,400 Americans over a period of 25 years. After the 25 years, the long trial period ended, the participants in the study were asked to answer a few questions that were designed to assess their cognitive abilities, like focus, memory, the ability to make quick decisions, and others of that sort.

According to the results of the extensive study, individuals that smoked pot on a regular basis (usually daily) for a long period of time (more than five straight years) presented a less developed verbal memory than those who did not smoke at all or those who smoked less frequently.

In order for the results to be as accurate as possible, the researchers eliminated other factors that affect that cognitive performance such as education, age, other substances use or abuse and depression.
For better organizing the data they collected, the scientists measured the marijuana exposure in “marijuana years”. Basically, individuals that smoked marijuana every day for a year completed a marijuana year or those who smoked once every two days completed a marijuana year in two years time, and so forth.

The results were clear because the data was linear. The more frequent the marijuana consumption, the bigger the memory loss.

In order to determine the degree of memory loss, the scientists used a sample of 20 participants divided into two groups of ten individuals each. The volunteers were then given a 15-word list to memorize. After 25 minutes, they were asked to recall the 15 words.

The people who consumed marijuana occasionally or not at all were able to remember an average of nine words out of the given fifteen.

The second group, the ones that smoked marijuana regularly for over five years only managed to remember an average of 8.5 words. The difference between the two groups was of only half a word.

The gap between the two groups grows bigger as the regular marijuana use grows longer. But according to the data, only eight percent out of the total 3,385 participants in the study were exposed to marijuana use for more than five years.

The authorities are worried that in the case in which marijuana use is legalized, the substance will be overly abused.
But there is one variant that was not taken into consideration by the researchers. There might be a correlation between people that already have impaired cognitive function and a regular use of the substance. Further research is needed, but until then the scientific community cautions that marijuana affects our memory.

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