Smoking Pot makes stupid, lazy and hungry, so a common prejudice. But it is also true? According to a new study should be enough alone Trying hashish or marijuana to change the brain in a sustainable way. Parents are alerted. The investigation leaves many questions unanswered.

What did they find?

An international team of researchers analyzed brain scans of 46 youths, the scientists report in the journal “Journal of Neuroscience”. The 14-Year-old had consumed a once or twice Cannabis and otherwise of drugs.

It was shown that in regions of the brain, which bind with specific receptors for Cannabis in subjects, the volume of the so-called Gray matter, on average, was higher in comparison to the control group. The Gray matter is the part of the cerebrum that contains mainly nerve cells. “It only takes one or two Joints, Adolescents seem to be in the young to change the volume of Gray matter”, concluded Director of studies Hugh Garavan, from the U.S. University of Vermont.

The biggest difference, therefore, in two regions: the Amygdala, which plays a role in the emergence of anxiety and other emotions, and in the Hippocampus, for memory and spatial Thinking is important. But also in the cerebellum and other regions of the Grey substance was more present, the scientists write.

drug policy No fear of legal Cannabis

“Previously it was assumed that brain structural changes through regular and particularly early cannabis use can cause,” said Rainer Thomasius from the German centre for addiction issues of the child and youth age, which was not involved in the study.

limitations of the study

The study, however, it can be any occasion for further analyses, because it leaves open crucial questions. Because of the effects of the larger volume for the Affected, is unclear, as is the question of why Cannabis use should contribute to an enlarged Gray matter. May be a process disturbance, in which some synaptic Connections in the brain are reduced, speculated Garavan.

The study is in its explanatory power but, above all, is limited, because the researchers could not examine whether the young people had possibly smoked more than specified. Also, the number of subjects with 46 comparatively small. Whether an enlarged Grey matter in detail only on the consumption of two Joints, is therefore questionable. It could also be for other reasons.

in Addition, no blood was collected values to the actual recorded amount, for example, of THC – a psychoactive determine the active substance in Cannabis. The proportion of such substances can be in the case of Cannabis is very different. So at the end of December published a study of data from the EU, Norway and Turkey, to the conclusion that the average THC content in marijuana and hashish from 2006 to 2016, about doubled.

8.7 per cent of young people have already have smoked

Eva Hoch of the University hospital in Munich (LMU), to concerns that the study could not prove a causal relationship. The investigation will show, however, that early education about the effect of mind-altering substances, such as alcohol, tobacco, and Cannabis began had to be. “That may already be in the very low cannabis use in early adolescence adverse effects on brain development, this is an important message.”

According to the annual report of the German monitoring centre for drugs and drug addiction, 8.7 percent of 12 – to 17 have consumed Year-olds at least once in their lifetime.

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