Kurzgesagt - Wikipedia

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In 2015, the channel received a US$570,000 grant from the Bill and Melinda Gates Foundation,[12] who later became one of their key sponsors. Kurzgesagt have made videos calling for investment in novel technologies the foundation also supports, such as carbon capture and artificial meat, as well as arguing for an optimistic view on the future of climate change and economic inequality, a view shared by Bill Gates.[22][23]

Since September 2017, Kurzgesagt's German branch had been financially supported by the network Funk of ARD and ZDF. Kurzgesagt's German branch announced their departure from Funk in January 2023.[24][25][26][27]

In March 2022, Kurzgesagt received €2.97 million in a grant via Open Philanthropy,[28] which the channel said was being used for translating their videos into various languages, and for funding the creation of content for TikTok.[29] The channel has received a smaller grant from the John Templeton Foundation.[30]

In a January 2023 statement,[29] Kurzgesagt stated that 65% of their income from 2020 to 2022 came from viewers via the sale of merchandise from their shop, such as mugs, posters and toys, crowdfunding via Patreon, and Google AdSense revenue, with commercial or institutional sponsorships and grants accounting for only 24% of income. The statement said that the channel treats all data skeptically, that their sources for statements are always given, and that all research work is done in-house, with no editorial influence from sponsors or donors—a condition they say is included in every deal they have signed.[29] Kurzgesagt made this statement in response to a December 2022 video that was said to have accused them of having been "basically bought off by billionaires."[29]

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Biquette a dit:

Pour la partie dégâts au cerveau, je serais intéressé par un état de l'art sur les dommages causés à la myéline, parce qu'à ma connaissance il n'y a pas d'adaptation possible une fois les dégâts faits.

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Sorence a dit:

On sait que des abus abusifs

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Sorence a dit:

Concernant la myéline je n'en ai aucune idée, pourquoi tu parles de ça précisément ?

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Biquette a dit:

tu saoules, ça fait 2h que je lis

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In order to help minimize the damage caused by baseless neuro-claims regarding drug effects, you have to know how to read the methods and results sections of research papers that are purported to support these claims. I will now show you how to read these sections properly. For starters, you can ignore the introduction and discussion sections of most scientific papers. They usually serve as propaganda instruments to promote the research and ideas of the authors. For those uninterested in the details of this venture, I’ll give you the take-home message now: there are virtually no data on humans indicating that responsible recreational drug use causes brain abnormalities in otherwise healthy individuals. Trust me, if this were not the case, I would not so proudly proclaim within these pages my own lifelong recreational drug use.

For those of you who stuck around, I must now provide you with a basic level of understanding about a few commonly used brain-imaging techniques. They can be divided into two categories: structural and functional. Magnetic resonance imaging (MRI) is an example of structural imaging. MRI provides high-resolution images of the brain’s anatomy, pictures with a degree of focus ideal for detecting structural abnormalities, such as brain tumors or gross neuronal death. MRI procedures are said to be noninvasive because no radioactive chemicals are injected into the person being examined. An important drawback associated with MRI is that it provides no information about how the brain is functioning. It can tell you the size of a brain structure but not whether or how well that structure accomplishes a particular task. Simply knowing that my nucleus accumbens is larger than yours doesn’t mean that I experience more pleasure than you.

Positron-emission tomography (PET) and functional MRI (fMRI) are examples of functional imaging techniques because they can provide brain-activity information that is not available by simply looking at the brain’s anatomy. For example, the activity of a specific neurotransmitter can be obtained using a PET scan. Neither PET nor fMRI scans, however, provide information about the anatomy of the brain. But perhaps the most important limitation of PET is that it requires the injection of radioactive chemicals into the person being scanned, although the amount of exposure to harmful radiation is minimal.

Typically, these studies are conducted by recruiting two groups of participants: users of a particular drug and non–drug users. The non–drug users serve as the control group. During a study, each participant’s brain is scanned once, and they all complete behavior measures, such as cognitive tests. These scans and measures allow the researchers to determine whether there are behavioral differences between the groups. If so, the brain measures can help to determine the neural (or brain) source of the differences. But because brain images are typically collected at only a single time point for both groups of participants, it’s nearly impossible to determine whether drug use caused any observed differences. Any brain differences could have existed before the initiation of drug use. So, as you read the brain-imaging literature, be on guard for the inappropriate use of terms—such as alterations, atrophy, deterioration, and reductions, among others—that imply that a change has occurred. In order to measure a real change, multiple brain scans need to be completed at different time points. Can you tell if a person’s hair style has changed if you have seen the person only once in your life?

Study Finds Brain Changes in Young Marijuana Users. That was the title of an article printed in The Boston Globe on April 15, 2014. The piece was accompanied by a quote from Dr. Stuart Gitlow, then president of the American Society of Addiction Medicine, who remarked, “It’s fairly reasonable to draw the conclusion now that marijuana does alter the structure of the brain . . . and that structural alteration is responsible, at least to some degree, for the cognitive changes we have seen in other studies.”

The article and this conclusion were based on a recent MRI study conducted by researchers at Massachusetts General Hospital and Northwestern University.10 The researchers compared brain sizes of twenty cannabis users with twenty control participants by scanning the brain of each participant once. The average age of all research participants was about twenty-one. The cannabis users reported smoking the drug three to four days per week; they also smoked tobacco cigarettes and drank more alcohol than did the controls. The major finding was that, on average, cannabis users had a slightly larger nuclei accumbens and that the amount of reported cannabis use was correlated with accumbens size. The accumbens size differences were small, so small that if the brain scans of all participants were shuffled together into a single stack, it would be nearly impossible to correctly identify the group to which individual scans belonged. But this fact did not stop the investigators from concluding that their results demonstrated “morphometric abnormalities” and suggesting that marijuana exposure “is associated with exposure-dependent alterations” of brain reward structures.

The researchers’ interpretations, as well as those in the Boston Globe, are inappropriate because brain images were collected at only one time point for both groups of participants. This makes it impossible to determine whether there were any “alterations”; multiple brain scans over time for each participant would be required in order to measure a change. Also important, preexisting brain differences between the two groups cannot be ruled out. In other words, it’s possible that the small brain differences were there before the initiation of any drug use. This is a common mistake in the drug literature.

Another frequent oversight is to ignore the influence of tobacco smoking and alcohol use on the findings. In order to disentangle cannabis-related effects from those of tobacco and alcohol, the researchers should have included a third group of participants. This is almost never done in brain-imaging studies. Ideally, this group would have been composed of individuals who reported tobacco and alcohol use but not cannabis use. If the results of this third group were similar to those of the cannabis group, it would suggest that cannabis use was not responsible for the observed findings.

More important, though, there is no way to determine the everyday importance of the small structural differences observed in this study. As you might imagine, there is variability in the size of the nucleus accumbens among individuals. Some people have smaller ones; others have larger ones. Variability in the size range is considered normal, just as there is a range of normal height. Some people are shorter than others, but we would not characterize a five-foot-one woman as evincing “abnormality of stature.”

Another critical point is that the study did not include behavioral or cognitive measures. Simply knowing that there is a brain-structure size difference between two groups tells you nothing about the functional integrity of the brain or individual brain structures. For example, it’s highly likely that both groups would have performed equally well on a test measuring complex learning and memory or any other domain. Both groups of participants showed up, complied with study procedures, and completed the study. This demonstration of responsibility suggests that even the cannabis users met some basic level of functioning. Still, had the researchers included cognitive tests, for example, specific mental and intellectual information, as well as knowledge about how well brain structures were functioning, could have been deduced. Without carefully measuring a behavior of interest, such as cognition, researchers (and journalists) are often enticed into making unwarranted speculations about the neural basis of behavior. If you don’t measure behavior, then you can’t comment on behavior.

Unfortunately, most press coverage related to this study was equally irresponsible. Headlines in The Washington Post and Time declared, Even Casually Smoking Marijuana Can Change Your Brain, Study Finds and Recreational Pot Use Harmful to Young People’s Brains, respectively. Such story lines are typical when brain-imaging techniques are used to study drug users. Many of the studies are riddled with vital limitations, and the actual results frequently do not entirely correspond with conclusions drawn by the investigators. What follows are misleading headlines in the general press that are designed to frighten parents, who, in turn, implore their representatives to do something about the “drug problem.”

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there are virtually no data on humans indicating that responsible recreational drug use causes brain abnormalities in otherwise healthy individuals.

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Biquette a dit:

there are virtually no data on humans indicating that responsible recreational drug use causes brain abnormalities in otherwise healthy individuals.

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Biquette a dit:

"tenure" (je connais pas le mot français)

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