Can cannabis help a stroke patient recover

Marijuana: Cannabis stimulates the gray cells in the brain

"Gray cells" are popularly considered to be something good: an expression of the ability to think and intelligence. But it does not always have to be healthy when the amount of so-called gray matter (GS) in the brain increases.

That happens to adolescents who smoke weed - even if they rarely do it. A team of researchers from the USA, Great Britain, Germany and Austria published this discovery on January 14, 2019 in the Journal of Neuroscience.

Catherine Orr's team from the Department of Psychiatry and Psychology at the University of Vermont in the United States found that even very little cannabis consumption in adolescents causes measurable changes in the brain. Until the end of puberty, the brain is still in the growth phase and is therefore particularly sensitive to the active ingredient tetrahydrocannabiol (THC), which triggers intoxication when smoking weed.

More about gray cells: What does stress do to the brain?

Subjects had only smoked weed once or twice

With MRI images and so-called voxel-based morphometry, the volumes of cell types can be calculated

The researchers compared brain scans from 92 adolescents aged 14 years. Half of the subjects had already had experience with marijuana or hashish, the other half had not.

The scientists used what is known as "voxel-based morphometry" for this purpose. That means: They used images from a magnetic resonance tomograph (MRT) to record certain parameters in the brain quantitatively.

It found that gray matter had increased in volume in those who had only smoked weed once or twice, in the hippocampus and in the cerebellum. Neurologists commonly associate these areas with the endocannabinoid system. So this is the area of ​​the signaling system where the active ingredients of cannabis attach.

More on this: Toxoplasmosis parasites change the synapses in the brain

Gray matter - the center of our nervous system

Medical professionals refer to the nerve cell bodies and core areas of the central nervous system as gray matter. The white matter, on the other hand, consists primarily of the conduction pathways for the transmission of information. These are, for example, the nerve fibers and nerve cell extensions.

The color designation of the different areas of the nerve cells comes from the fact that the respective materials turn gray or white when they are placed in formalin. The solution is used to disinfect and preserve protein-containing biological preparations.

Formalin is used to disinfect and preserve protein-containing biological preparations

Danger to the brain: a stroke is often followed by dementia

Little basic research with smoking underage minors

The researchers did not want to decide whether the increase in gray matter should be considered useful or rather harmful. In any case, caution should be exercised when interpreting the data. One thing is certain: Doctors observe an increased number of anxiety disorders among adolescents who use cannabis.

Between 30 and 40 percent of adolescents in industrialized countries such as Germany and the USA have their first experiences with cannabis before they graduate from high school.

The medical professionals assume that this has long-term effects on the nervous system. However, there are few studies of adolescents who only use cannabis sporadically. Most scientific studies deal with adults who have used cannabis extensively for many years.

  • Squirrel: Planning the nut hiding places increases the brain size

    Fast climbers with enormous jumping power

    Squirrels are the kings of the trees. Its conspicuous bushy tail serves as a steering and balance oar during daring jumps from tree to tree. In addition, the extraordinary anatomy of the ankle allows the feet to be rotated 180 degrees backwards, for quick head-down climbing on tree trunks.

  • Squirrel: Planning the nut hiding places increases the brain size

    Diverse menu

    The food on offer for the small rodents varies depending on the season: if it is fresh buds and young shoots and seeds in spring, the buffet is richly stocked with delicious fruits, nuts, mushrooms and berries in summer and autumn. But squirrels also have to eat in the cold season, after all, they do not hibernate.

  • Squirrel: Planning the nut hiding places increases the brain size

    Laborious collecting and hiding

    Therefore, the rodents have to accumulate a large supply of food in autumn. When looking for and storing nuts, there are a few things to consider: Where is the perfect hiding place that can be found again in the end? Which nut meets the quality criteria in order to be hidden at all? This requires a lot of thought from squirrels during the autumn collection campaign.

  • Squirrel: Planning the nut hiding places increases the brain size

    Much nut, much brain?

    Researchers at the American University of Berkeley have now found that some squirrels think so much about nuts and their storage in the fall that their brains are much larger during this time of year than the rest of the year.

  • Squirrel: Planning the nut hiding places increases the brain size

    Lots of nut hiding spots

    The enlargement of the brain is particularly evident in the gray squirrels: They bury their stocks widely scattered in their territory and thus have numerous hiding places that they have to remember. Red squirrels, on the other hand, tend to bury their delicacies point by point - and then defend the supply from possible food thieves.

  • Squirrel: Planning the nut hiding places increases the brain size

    Quality control like on an assembly line

    But not only the right storage location is an important criterion for the winter supply - the quality of the nut must also be right: The researchers assume that squirrels use a certain head movement to check the weight of a nut and use their fine paws to check the freshness and condition check the shell. Every single nut is examined with painstaking precision.

  • Squirrel: Planning the nut hiding places increases the brain size

    Recovery through mental maps

    The sense of smell is not the only thing that helps to find it again: Researchers found that the rodents, with foresight, bury the nut species sorted from one another. This allows the rodents to remember the hiding places better - and that helps them survive. Because the faster a squirrel finds its supply, the quicker it can get back into its warm and safe nest.

    Author: Sabrina Walker

  • These sports damage the brain


    Wrestling is not just a show. Because one thing is certain: the brains of some wrestlers are seriously damaged thanks to repeated head injuries. When Canadian wrestler Chris Benoit shot himself at the age of 40, doctors found that his brain resembled that of an 85-year-old Alzheimer's patient.

  • These sports damage the brain


    Doctors even have a name for this disease: chronic traumatic encephalopathy, or just Boxer's syndrome. And it means: constant bumps against the head change the brain - for the worse. The result is memory loss, language difficulties, thoughts of suicide and finally dementia. The disease was first discovered in professional boxers, hence the name.

  • These sports damage the brain

    American football

    Boxer syndrome doesn't just affect boxers. The disease is particularly common among American football players. According to Science magazine, the average National Football League player suffers over 600 hits on his head over the course of a season. Even the hard-shell helmets cannot fully absorb the impact.

  • These sports damage the brain

    Protect helmets (a little)

    The National Football League denied for many years that its players could be affected by boxer syndrome. In the meantime she has given in and changed a few rules of the game to prevent head-to-head collisions. At the same time, researchers are working on magnet inserts for football helmets. Repulsive forces are designed to soften a collision before it happens.

  • These sports damage the brain

    ice Hockey

    If you want to avoid brain damage, you are not allowed to play ice hockey: some hockey players have already been diagnosed with boxer syndrome. Regardless of whether a collision is intentional or just an accident: In the long term, impacts on the head lead to an accumulation of dangerous proteins in the brain.

  • These sports damage the brain


    It seems absurd, but yes: Even soccer players are at risk - from their headers. The forces at work seem harmless compared to the violent blows in an American football or ice hockey game. But even small forces can add up over time.

    Author: Brigitte Osterath