How cannabis causes 'cognitive chaos' in the brain

Cannabis use is associated with disturbances in concentration and memory. New research by neuroscientists at the University of Bristol, published in the Journal of Neuroscience, has found that brain activity becomes uncoordinated and inaccurate during these altered states of mind, leading to neurophysiological and behavioural impairments reminiscent of those seen in schizophrenia.

The collaborative study, led by Dr Matt Jones from the University's School of Physiology and Pharmacology, tested whether the detrimental effects of cannabis on memory and cognition could be the result of 'disorchestrated' brain networks.

can be compared to performance of a philharmonic orchestra in which string, brass, woodwind and percussion sections are coupled together in rhythms dictated by the conductor. Similarly, specific structures in the brain tune in to one another at defined frequencies: their gives rise to , and the tuning of these brain waves normally allows processing of information used to guide our behaviour.

Using state-of-the-art technology, the researchers measured from hundreds of neurons in rats that were given a drug that mimics the psychoactive ingredient of marijuana. While the effects of the drug on individual were subtle, the drug completely disrupted co-ordinated brain waves across the hippocampus and prefrontal cortex, as though two sections of the orchestra were playing out of synch.

Both these brain structures are essential for memory and decision-making and heavily implicated in the pathology of schizophrenia.

The results from the study show that as a consequence of this decoupling of hippocampus and prefrontal cortex, the rats became unable to make accurate decisions when navigating around a maze.

Dr Jones, lead author and MRC Senior Non-clinical Fellow at the University, said: "Marijuana abuse is common among sufferers of schizophrenia and recent studies have shown that the psychoactive ingredient of marijuana can induce some symptoms of schizophrenia in healthy volunteers. These findings are therefore important for our understanding of psychiatric diseases, which may arise as a consequence of 'disorchestrated brains' and could be treated by re-tuning brain activity."

Michal Kucewicz, first author on the study, added: "These results are an important step forward in our understanding of how rhythmic activity in the brain underlies thought processes in health and disease."

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Isaacsname
3.5 / 5 (13) Oct 25, 2011
" Using state-of-the-art technology, the researchers measured electrical activity from hundreds of neurons in rats that were given a drug that mimics the psychoactive ingredient of marijuana. "

There are multiple cannabinoids, hence the " s " to signify a plural.

What a biased and BS " study ".
JRDarby
4.4 / 5 (19) Oct 25, 2011
Wait a second...

the researchers measured electrical activity from hundreds of neurons in rats that were given a drug that mimics the psychoactive ingredient of marijuana.


(1) They didn't administer actual cannabis. (2) They didn't administer the correct cocktail of chemicals that would mimic cannabis. There are around SIXTY active ingredients in cannabis, not one, and there are well-established moderating and limiting effects between the different chemicals on each other. (3) There is no mention of dosage, either absolute or relative to human consumption. (4) The link between schizophrenia and cannabis (ab)use is, at best, a correlation. Additionally, noting that cannabis use can induce some symptoms of schizophrenia after positing the correlation is disingenuous. Myriad stimuli can induce schizophrenia-like symptoms, but these are never mentioned here or in public discourse, nor are they controlled for in many other studies.

JRDarby
4.3 / 5 (17) Oct 25, 2011
Furthermore, there are several endocannabinoid systems in the human brain. For the Greek-challenged, "endo" means "internal." In other words, there are several natural cannabinoid systems in the brain that produce, metabolize, and excrete chemicals like those found in the plant itself.

http://en.wikiped...d_system

Perhaps the researchers' grant money would be more productively spent studying the relation of these UBIQUITOUS endocannabinoid systems to schizophrenia than it is spent here--demonizing cannabis, the use of which is NOT ubiquitous, for what are quite obviously public policy reasons.

At the very least, if they want scientifically valid results, they should at least conduct the science correctly (see my post above).
JRDarby
4.2 / 5 (18) Oct 25, 2011
And just to show you that I do my homework, look at this little gem I found on the actual article: (PhysOrg: Why did you copy and paste the ENTIRE article EXCEPT for this statement?)

http://www.bris.a...985.html

The research is part of a Medical Research Council (MRC)-supported collaboration between the University and the Eli Lilly & Co. Centre for Cognitive Neuroscience...


It would be stupid to immediately dismiss the findings due to the direct financial link to a pharmaceutical megacorporation who has an obvious interest in preventing the legalization of cannabis for medicinal purposes, but critical and inquiring minds should at least take into account the source of funding for this study.
pauljpease
4.6 / 5 (11) Oct 25, 2011
Thanks JRDarby! I have no doubt that cannibinoids affect brain activity, what did they expect to find. And the regions affected are involved in a lot of things, they're not like the "schizophrenia" part of the brain or something. My main point though is that even if it messes up memory and makes you confused, it is temporary, and often these effects have benefits for some people. Every article that makes negative statements about cannabinoids should be required to state "but the negative effects are mild compared with the negative effects of moderate alcohol consumption."
JRDarby
3 / 5 (4) Oct 25, 2011
Thanks for the triple 1-star ratings, SmaryJerry. I'd really love to hear why you thought my comments deserved what you gave them, and also your opinion on the article itself given your ratings.
paulo
4.3 / 5 (9) Oct 25, 2011
Wouldn't it have made more sense to use actual cannabis in a study about cannabis?
Matt_J_
3 / 5 (4) Oct 25, 2011
It would make more sense to read the actual study in the Journal of Neuroscience rather than a simple summary before asking detailed questions about the study. Unless you're on dope.
cmn
5 / 5 (9) Oct 25, 2011
They probably didn't use Marijuana itself because the accuracy of dosage (THC/CBDs/etc) can vary within the plant, even if the levels are test a prior, and the administration itself can affect the absorption levels (smoked/eaten/etc). It would make more sense, scientifically, to inject something synthetic like Marinol or one of the JWH's where the dosage can be exactly measured.

Not to mention, have you ever tried to get a mouse to smoke a joint?!? I mean, rolling a normal sized joint is hard enough, try rolling one mouse sized! ;)
mocpl
5 / 5 (5) Oct 25, 2011
Number one anyone who has smoked Marijuana had some form of paranoia. So I would not doubt something I have known for years. Now, once you have smoked Cannabis daily and have become chronic, you know what I mean, you will loose some of the side effects of paranoia and you will just become sedated. Have you ever saw people who are chronic drive, take test, study at school; take some little mouse that is just starting his or her dose and of course she will be confused about the maze and just sit down until it passes. I would like to see a more detail study involving the life of the suspect and see what brain changes if any occurs. Greg
YawningDog
2.6 / 5 (5) Oct 25, 2011
More junk "science". Can't somebody find these people jobs at McDonald's?
Cave_Man
3.1 / 5 (7) Oct 25, 2011
They probably didn't use Marijuana itself because the accuracy of dosage (THC/CBDs/etc) can vary within the plant, even if the levels are test a prior, and the administration itself can affect the absorption levels (smoked/eaten/etc). It would make more sense, scientifically, to inject something synthetic like Marinol or one of the JWH's where the dosage can be exactly measured.

Not to mention, have you ever tried to get a mouse to smoke a joint?!? I mean, rolling a normal sized joint is hard enough, try rolling one mouse sized! ;)


I've got some stingy friends who roll mouse size joints on a regular basis, however the amount of paper in these joints is probably greater than any cannabis.

I never understood non-user agression toward users of cannabis.
It's like they really don't want to see people having harmless fun. Most users of cannabis are mild mannered and quite philosophical, the ones who aren't would probably be the idiots they are with or without cannabis.
PeerPride
3.7 / 5 (6) Oct 26, 2011
They probably didn't use Marijuana itself because the accuracy of dosage (THC/CBDs/etc) can vary within the plant, even if the levels are test a prior, and the administration itself can affect the absorption levels (smoked/eaten/etc). It would make more sense, scientifically, to inject something synthetic like Marinol or one of the JWH's where the dosage can be exactly measured.

Not to mention, have you ever tried to get a mouse to smoke a joint?!? I mean, rolling a normal sized joint is hard enough, try rolling one mouse sized! ;)


The reasons are unimportant. This study shouldn't even mention the word cannabis. It should refer only to the drug they administered to the rats, which is not mentioned as it were.

Moreover, in side to side trials inorganic thc-substitutes have different effects on the human body than smoked marijuana. (i.e. JWH-018 can cause seizures when smoked)

This is propaganda "science".
h20dr
3.4 / 5 (5) Oct 26, 2011
This article cracks me up! Rats? Really? Why don't they just go stand outside a dispensary in CA and ask for volunteers? I am reporting this to PETA!
antonima
1 / 5 (2) Oct 26, 2011
I think its important to document both the pros and costs of marijuana use. Drinking is legal, and it seems that the costs are much higher than with cannabis, but perhaps they do not entirely overlap.
jamesrm
3.9 / 5 (7) Oct 26, 2011
This is your Brain: Play some Brahms
This is your Brain on pure synthetic 9THC: Play some Stravinsky

One of our science shows (in Oz) had a reporter try a natural THC mix versus pure-D9THC, the natural mix found her very happy and laughing, the synth sent her off to panic-land, a massive difference. I think these poor rodents were seeing cats coming out of the woodwork.
baudrunner
3.4 / 5 (8) Oct 26, 2011
All living conscious and cognizant entities/life-forms conduct their lives with what they have to work with. While experimentation on rats can be very productive, I don't think that a rat would ever be compelled to run down to the corner to score some weed. Humans are a different animal, however. I know of only one who likes driving his car around when he gets high, but I think that's not wise. People use marijauna in a safe environment to have a laugh or get into some creative pursuit like painting or playing or appreciating music. I'm sure that the things that run through a person's mind are not the same as what's in a rat's mind when under the influence, so any conclusions drawn from the experiment to the effect that the results are in any way analagous to effects on humans are bogus.

Furthermore, between the Sativa and Indica varieties there exist around two hundred hybrids, all of which have some different kind of effect on the human brain. Hardly a scientific study.
baudrunner
2.3 / 5 (3) Oct 26, 2011
Furthermore, the article is titled "How cannabis causes 'cognitive chaos' in the brain". I can't find that out in this article, but then, I'm more looking for molecular biological processes.
Bonkers
3 / 5 (2) Oct 26, 2011
This is a prime example of "policy-based evidence", (here in the UK our government is committed to evidence-based policy, except when it disagrees with their prejudices) - the statement that "many schizophrenics take cannabis" is pure sophistry, attempting to imply a causative link.
WTF is it to do with any baby-kissers, shouldn't they be focusing on other stuff, like the economy?
I've said it before, consenting adults in private should be allowed to do whatever they like, that is the freedom you are afforded for being a reasonable member of society, there is supposed to be a payback. If they want to smoke some weed, then I don't see what it has to do with anyone else.
Personally I find a little smoke helps me solve intricate technical problems, for the most part.
So, beneficial or at very least harmless, in moderation, - get over it big Pharma and big brother.
hyongx
5 / 5 (3) Oct 26, 2011
matematically, a 'chaotic' system is one that is very sensitive to variations of initial conditions. i would say that cognition is at least a stochastic process, already, if not intrinsically chaotic. all these headlines are phrased by journalists, not scientists, anyway.
in these kind of topics, though, people always just believe what they want to believe.
that_guy
4.2 / 5 (5) Oct 26, 2011
I propose a follow up study where you induce a state of cannibinoid cognitive chaos in a bunch of potheads, and then tell them that marijuana is a worse drug than cocaine or amphetemine (According to US law...MJ is schedule I, while Coke and amphetemine are schedule II)

Then we can monitor the results. According to my research into the comments section of physorg, potheads tend to jump immediately into a state of coherence when the subject concerns marijuana.

According to the requirements for a schedule I drug, marijuana has the following properties:

-A high potential for abuse.
-No currently accepted medical use in treatment in the United States.
- There is a lack of accepted safety for use of the drug or other substance under medical supervision.

That last one means that it is considered unsafe to use marijuana even under direct medical supervision (Which is why they need a federal exception even to study real MJ)

have a nice day guys.
Cave_Man
2.3 / 5 (3) Oct 26, 2011
I propose a follow up study where you induce a state of cannibinoid cognitive chaos in a bunch of potheads, and then tell them that marijuana is a worse drug than cocaine or amphetemine (According to US law...MJ is schedule I, while Coke and amphetemine are schedule II)

Then we can monitor the results. According to my research into the comments section of physorg, potheads tend to jump immediately into a state of coherence when the subject concerns marijuana.

According to the requirements for a schedule I drug, marijuana has the following properties:

-A high potential for abuse.
-No currently accepted medical use in treatment in the United States.
- There is a lack of accepted safety for use of the drug or other substance under medical supervision.

That last one means that it is considered unsafe to use marijuana even under direct medical supervision (Which is why they need a federal exception even to study real MJ)

have a nice day guys.


Good one!
Cave_Man
3 / 5 (4) Oct 26, 2011
I really think hallucinogens need a more prominent role in our society, they have been used for thousands of years for a reason and that reason is not to have fun, it is to gain knowledge of the universe that is only attainable once you recognize the tangible aspect of reality (or lack thereof).

What remains constant when under the effects of mushrooms? What changes? You can't learn about it accurately in a lab you must use your instincts and deeply ingrained though processes to decipher the unimaginable variation present in normal perception and altered perception.

Personally, I've seen the (my) meaning of the universe, it exists in my mind in a different language than everything else in there and it's quite useful in terms of dealing with new experience that I would normally have trouble integrating, like death or drastic changes to lifestyle.

I think most religion is an attempt to codify the knowledge gained by altered states into an easy to understand guideline of moral behavior
Smashin_Z_1885
3 / 5 (2) Oct 27, 2011
This article is Absurd, and NOT scientific in any way. In fact, this supposed "study" violates every step in the scientific process. 1. Study subject is a rodent (not a human). 2. Study substance is an UN-Named synthetic drug (not the actual drug supposedly being studied. 3. Results are assumed, based on, once again, the absurdity that cannabis is somehow "bad" for humans to consume. . Keep in mind, please, that cannabis has been in use by humans for at least 4600 years, or more. Furthermore, it is a proven FACT, that cannabis is 100% non-toxic. It is the safest known plant-based material on the planet, in any form; smoked, eaten, etc. it does not matter how the plant is consumed, no physical or mental damage can become of it's used, period. And that is a FACT. No other plant on this Earth can claim such a safety record, not even vegetables which we eat (of which many can cause gout, allergic reactions, or contain various toxic substances naturally, such as potatoes, spinach, etc.)
that_guy
not rated yet Oct 27, 2011
I really think hallucinogens need a more prominent role in our society...

What remains constant when under the effects of mushrooms? What changes? You can't learn about it accurately in a lab...

Although you can always argue about the subjectivity of 'spirituality' of certain experiences - They are able to scientifically cover far more ground than you think.

There was a great scientific article on physorg or med express a few weeks back regarding how mushroom experiences can incur permanent life changing effects in a person to be more open/empathetic, etc. I highly recommend that you find it - I think you'll like it.
Skultch
3.7 / 5 (3) Oct 27, 2011
These results are an important step forward in our understanding of how rhythmic activity in the brain underlies thought processes in health and disease.


Let's not get TOO worked up over this badly summarized experiment. If it merely brings us one step closer to understanding the incredibly complex disorder called schizophrenia, then I'm glad it was conducted.

That said, we have a long way to go, in the US at least, to communicate the individual health advantages of cannabis use. I also happen to advocate the legalization of recreational use, for the obvious civil liberty benefit in relation to the low societal risks.

THAT said, I am somewhat concerned about increasing widespread acceptance of driving while intoxicated with cannabis. Driving "high" is considered safer than driving drunk, and in IMHO is, however, we cannot ignore the impacts to public safety that will inevitably come from teens experimenting with BOTH, then driving. How much worse is the combination?
Twin
1 / 5 (1) Oct 27, 2011
Responses here are as hot as in AGW articles
Arkaleus
1 / 5 (2) Oct 28, 2011
I wonder what the baseline for cognitive chaos would be if the human test subjects were drawn from American mass media consumers, and the test was to describe how the world worked and who ran it.

Would the cannabis users score better? Does cognitive chaos have more to do with how the brain interprets information, rather than how it organizes its own internal communications?
Skepticus_Rex
1 / 5 (3) Oct 29, 2011
I personally know a person whose IQ was tested both before and after cannabis use. It was found that he actually had lost 30 points off of his IQ after a few years of use. He was dropped from genius level to high IQ. It was tragic to watch.

That was not the worst. Others I also knew were negatively impacted from heavy use over a period of a decade or more, some developing mental conditions and yet others with anxiety to the point of needing anxiety medications to control it unless they remained doped up on cannabis. Almost everyone I knew who used the stuff with any regularity showed signs of cognitive decline in one way or another.

It does not affect every one the same way, however, and I acknowledge that. Perhaps there are other mitigating factors that have not yet been considered for some.
moosefoot
5 / 5 (2) Oct 30, 2011
Not saying that your praise of cannabinoids is completely unfounded... the fact that any article/study that as much as hints at anything even remotely negative about cannabis gets flooded by these comments is a little worrying though. While there is a lot of potential in cannabis-derived medicine and that its label as an evil death drug is unjust, it still has the potential to cause a plethora of negative effects. Get over it. It occurs to me as the typical conspiracy theorist thing, you know. Studies with positive results are great while studies with negative results are obviously conducted by shady scientists bribed by the government...
Skultch
3 / 5 (2) Oct 31, 2011
I personally know a person whose IQ was tested both before and after cannabis use. It was found that he actually had lost 30 points off of his IQ after a few years of use. He was dropped from genius level to high IQ. It was tragic to watch.


There's almost no way that was caused by cannabis alone; dude was probably rolling and tweaking on the side. Clearly, everyone reacts differently, but endocannabinoids have not been found to affect /existing/ long term memory OR persistently affect formation. Yes, they affect short term and the formation of long term memories /during/ the psychoactive period, but I have yet to see any experimental evidence that suggests your claim is even plausible.

Anecdotes like that have little value; like this one: I know several "perma-stoners" that have smoked all day every day for over 10 years. No less than three of them manage companies with more than 50 employees and ski expert terrain that could kill; you can't do that with below average IQ.
Skultch
1 / 5 (1) Oct 31, 2011
it still has the potential to cause a plethora of negative effects. Get over it.


And your point is...?

So, it's not a miracle substance; the first ever to not have negative side effects? What exactly are we supposed to "get over?" I'm supposed to just accept that our civil liberties are unreasonably curbed? Sorry, I'm not going to get over that for no other reason than weed ain't perfect.
jway
3 / 5 (2) Nov 01, 2011
Is that *all* that happens?! Banning stores from selling legally-grown marijuana to adults draws drug dealers into our neighborhoods and has provided the Mexican drug cartels with the ability and incentive to brutally murder more than 40,000 people in the last five years. And yet we stick with the ineffective prohibition because it causes people to think a little different. What a shame!
jway
1 / 5 (1) Nov 01, 2011
I personally know a person whose IQ was tested both before and after cannabis use. It was found that he actually had lost 30 points off of his IQ after a few years of use.


And I personally knew a person who was tortured, murdered and mutilated by one of the cartels in order to "protect" their largest cash flow - selling marijuana in the U.S.

Prohibitionists like you like to call marijuana a "harmful substance", but marijuana is far LESS harmful than beer and wine which are LEGAL, and is also far LESS harmful than the federal marijuana prohibition which causes the arrest of 850,000 people every year and draws drug dealers into our neighborhoods and around our children. It's a disgrace for people like you to put our children in danger just because you have a problem with the way other people choose to relax!