How does cannabis affect the brain?
Some do it daily, some even several times a day. There are stoners for whom a joint is part of everyday life as naturally as butter on bread or coffee with cake.
The brain of these Cannabis users is constantly flooded with THC, the main active ingredient in cannabis.
This is especially true when using highly potent cannabis strains.
How harmful is cannabis to the brain?
There are a number of partially contradicting research results on the question if and how harmful is cannabis to the brain.
For this reason, researchers from the Center for Medical Cannabis Research at the University of California collected and analyzed all available research results on the neurocognitive effects (effects on the brain) in long-term users in 2003
Few studies provide reliable results.
Of the 1,014 studies identified that examined neurocognitive functions in cannabis users, only 15 studies could meet methodological criteria that produce reliable results.
These 15 studies include 704 long-term cannabis users and 408 non-users.
The neurocognitive studies, examines the response time, learning ability, memory and attention and no brain damage was found – but impaired learning and memory performance where low.
After summarizing and analyzing all the results of the study, the researchers came to the conclusion that there was no substantial loss in cognitive brain functions.
However, there were slight losses in the areas of learning ability and memory.
“Surprisingly, we have hardly found any evidence of harmful effects (related to brain performance).
The only exception is an extremely small effect when learning new information, “said Prof. Igor Grant, head of the study.
In addition, the restrictions in brain performance that were found could not be attributed with absolute certainty to cannabis, since the consumers may also have previous burdens – e.g. have had previous use of other drugs.
Brains of children and adolescents are more vulnerable to the negative effects of Cannabis use.
Adolescents who use cannabis show a long-term change in brain structure.
In one study, cannabis was taken by several people at different frequencies over a long period of time.
One group used cannabis regularly in moderate amounts, while the other participants used cannabis extensively. After all, you should stop using it completely for a month.
The brain had fully recovered from the moderate users. In the group with the extensive consumers, however, brain performance had not yet returned to the original level even after one month of abstinence.
Irreversible changes in adolescents
Using Cannabis demage the ability to learn new information
In a test to determine the ability to make decisions, people with long-term Cannabis consumption over 10 years achieved particularly bad scores: their results were 70 percent below the norm.
The results of consumers with an experience of between 5 and 10 years were 55 percent below normal, while the results of the control group were only 8 percent lower.
Dr. Messinis sums up: “The longer the participants consumed marijuana, the more their cognitive abilities were impaired, especially their ability to learn new information.”
Effects on everyday life
Researches were made to check the effects of Cannabis consumption on everyday life.
In a study, the test subjects had to fill in special questionnaires in addition to the usual brain performance tests, in which they provide information about their everyday memory.
It dealt with the small failures in everyday life such as forgetting appointments or other things that you actually wanted to remember.
Since it is such a thing with the self-declaration, friends and relatives were asked to estimate how often the test subjects make mistakes in everyday life.
- The results provide a two-part picture:
No significant differences between cannabis users and abstinent people were found in the brain performance tests in the laboratory.
Cannabis use therefore has no influence on the performance of the brain. - On the other hand, significant effects on the everyday life of consumers were demonstrated: the people in the cannabis group admitted errors in everyday life significantly more often. The self-assessments also coincided with the statements of friends and relatives.
In their study, the team of authors argues that cannabis users can concentrate under laboratory conditions and can deliver the same services as abstinent people.
In real life, however, they would be easier to be distracted and consequently also show small memory problems and other failures more often than abstinent people.
“Even if cannabis users have shown normal performance in the laboratory, this does not mean that THC has no effect on the underlying neuronal structures,” the team of authors concludes in their study.