Cannabis increases the noise in your brain

Cannabis indica. Credit: Wikipedia

Several studies have demonstrated that the primary active constituent of cannabis, delta-9-tetrahydrocannabinol (∆9-THC), induces transient psychosis-like effects in healthy subjects similar to those observed in schizophrenia. However, the mechanisms underlying these effects are not clear.

A new study, published in the journal Biological Psychiatry, reports that ∆9-THC increases random neural activity, termed neural noise, in the brains of healthy human subjects. The findings suggest that increased neural noise may play a role in the psychosis-like effects of cannabis.

"At doses roughly equivalent to half or a single joint, ∆9-THC produced psychosis-like effects and increased neural noise in humans," explained senior author Dr. Deepak Cyril D'Souza, a Professor of Psychiatry at Yale School of Medicine.

"The dose-dependent and strong positive relationship between these two findings suggest that the psychosis-like effects of cannabis may be related to neural noise which disrupts the brain's normal information processing," added first author Dr. Jose Cortes-Briones, a Postdoctoral Associate in Psychiatry at Yale School of Medicine.

The investigators studied the effects of ∆9-THC on in 24 human subjects who participated in a three-day study during which they received two doses of intravenous ∆9-THC or placebo in a double-blind, randomized, cross-over, and counterbalanced design.

If confirmed, the link between and psychosis could shed light on the biology of some of the symptoms associated with schizophrenia.

"This interesting study suggests a commonality between the effects on the brain of the major active ingredient in marijuana and symptoms of schizophrenia," stated Dr. John Krystal, Editor of Biological Psychiatry. "The impairment of cortical function by ∆9-THC could underlie some of the cognitive effects of marijuana. Not only does this finding aid our understanding of the processes underlying psychosis, it underscores an important concern in the debate surrounding medical and legalized access to marijuana."

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More information: Jose A. Cortes-Briones et al. The Psychosis-like Effects of Δ9-Tetrahydrocannabinol Are Associated With Increased Cortical Noise in Healthy Humans, Biological Psychiatry (2015). DOI: 10.1016/j.biopsych.2015.03.023
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Citation: Cannabis increases the noise in your brain (2015, December 3) retrieved 21 January 2019 from
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Dec 03, 2015
So an isolated THC-only solution without any of the other cannabinoid, terpenes or flavonoids present in whole cannabis - whether in the raw product or the extracted solution - produces "psychotic"- like episodes. This has been known for a long time now.

What is more significant is the "entourage effect" and the fact that CBD and the other cannabinoids, terpenes and flavonoids found in whole plant products mitigate and modulate the negative psychoactive effects of THC-only or high THC/low CBD content cannabis products like the one used in this study.

In a recent British study of psychotic-like episodes produced by high THC/low CBD strains of "skunk" weed they found that people who consumed hash did not have any off these negative psychoactive effects. The reason is that hash in Europe is imported from third world countries that make the hash from naturally growing unadulterated non hybridized landrace strains that are high in CBD content unlike high THC skunk.

Dec 03, 2015
Another misleading and fear mongering article.

Dec 03, 2015
After 13 years at the NW Pain Clinics I've experienced first hand, the best modern pain treatment that current medicine has to offer. I've also come closer to death from them than I like to admit. Had I chose to continue to listen to the majority of my pain docs on this topic, I would most certainly BE DEAD!

I never expected to be another one of those people that swear that "MARIJUANA SAVED THEIR LIFE" but I know in my heart that it's the truth.

I can also tell you from my own personal experience, w/o even the slightest bit of doubt, that drug companies have partnered with insurance companies and are now running our health care for profit and not your wellbeing. You are an absolute FOOL if you believe otherwise!!! There for I expect that anything that works half as well as marijuana on pain would be highly suspect to many more of these very unfounded cheap & quick studies in order to disprove what so many like myself have found: THEY ARE ALL JUST MORE OF THE SAME OLD BS!!!

Dec 03, 2015
"24 human subjects who participated in a three-day study during which they received two doses of intravenous ∆9-THC"

They found that out all on one weekend study? And the drug was given iv? And none of the other MJ components were given. I do know there were studies in England about the paranoid effects of THC. They found people given THC by itself in pure form got paranoid. They also found that if people took thc with all the other stuff that you get in MJ the paranoid effects did not appear. There is more to MJ than just thc. THC is just one component in MJ and in the oils of MJ. So you can't conclude that people who smoke weed will become psychotic or even increase the "noise" in their heads. It's one study not a long term study and it leaves out the after effects and long term possible after effects. I think that if it turned people psychotic I would be raving mad by now and probably would have happened years go. Have not heard any voices yet....

Dec 03, 2015
NO IT DON"T ! I've been told (actually read) don't bring alcohol into the argument .Well I will Many times I've had the experience observing drunk individuals jabbering ,ranting carrying out conversations with "NO ONE!". This is not uncommon for someone who enters an alcohol blackout.sometimes funny and often dangerous.With cannabis as a seventy year old I never ever experienced anyone with "Schizoid" behavior /symptoms etc. Also the drug alcohol is not a beverage again it's a drug that can cause mind disorders on a major scale such as Wernicke–Korsakoff syndrome (WKS), also called wet brain, Korsakoff's psychosis, and alcoholic encephalopathy.

Dec 03, 2015
If cannabis was legal we could put warnings like this on the packets, but we can never make that happen while it's kept illegal. We need to legalize cannabis as a far safer alternative to alcohol!

Dec 03, 2015
Its a small study, but it makes sense. Disrupting the normal brain process, isnt that getting high? It interesting that they may be able to use marijuana components to study schizophrenia. This could lead to better treatments using the CBDs that level out your buzz to help level out some of schizophrenia effects. This could be a positive thing for marijuana.

Dec 03, 2015
What was that?

Dec 03, 2015
Many of the murderers in mass shooting and suicide bombings have induced psychosis from drug use -- but not from cannibis.

There are MANY drugs and environmental exposures that induce schizophrenia and psychosis. In fact, schizophrenia has become a silent epidemic with many developing the disease late in life do to environmental and 2nd hand exposure.

1st, 2nd or 3rd hand methamphetamine exposure is creating millions of new schizophrenia cases each year. Meth was effectively used by Nazis as a way to allow normal soldiers to become psychotic murderers. It is still used today by our own military to create the same level of mental alertness and satanic murdering efficiency, like that displayed by those punks in San Bernadino yesterday. Unfortunately, meth is almost impossible to detect by our measurements and the public is grossly calm over the subject partially because Hollywood glamorized meth in Breaking Bad.

Dec 03, 2015
Still trumps Alcohol.

Dec 03, 2015
A better way of looking at it is cannabis and psychedelics reduce the filter we put on top of reality. The filter is a good and useful thing (for driving in traffic and running away from dangerous predators) but it is not reality. Reality is infinite, as in the more you look, the more you see. You can experience everything drugs can show you in deep meditation but most people don't want to put in the effort. So, yes, you do have more stuff going on in your mind, and it is similar to psychosis, but you would have to do extreme amounts of weed to get that high, and pot ingestion tends to be self limiting. Other psychedelics are order of magnitude stronger and should be treated with respect.

Dec 04, 2015
Welllllll Duh, it's a serotonin agonist! And that says nothing about the subjective experience, having more noise is one thing, having a hippocampus to filter it is another. That's to say it's one thing to be stimulated, it's another thing to derive meaning from the experience. And that goes for any human experience, chemically enhanced or otherwise. And as other posters have pointed out, cannabis is not just THC (or one chemical isomer i,e, delta 9) it's a mixture of agonists, antagonists and synergists of both. The study is as meaningless as using pure ethanol to extrapolate the theoretical experience of enjoying an aged single malt whiskey.

Dec 04, 2015
These studies are convoluted, in that the tests subjects are first time users of the drug being tested. Those that use alcohol for the first time experience a totally different response to alcohol than those that are accustomed to alcohol.

My, my, how much more money will big pharma pay for such lies and distortion, just so that they can continue to profit via lie filled propaganda.

Dec 04, 2015
Reefer Madness strikes again - in the 21st Century! - This is just more junk science propaganda.

If marijuana were a significant cause of schizophrenia, we would have had a corresponding explosion of that mental illness in the sixties and seventies when consumption went from a few thousand to several million - in this country alone. - We didn't, of course.

The authors also fail to mention THC is actually produced by the brain. That's why we have THC receptors - duh. - Further, decades of research have shown marijuana doesn't harm the brain. In fact, science has shown marijuana relieves the symptoms of most schizophrenic patients, can reduce the deadly swelling from brain trauma, gives the brain more stamina, prevents/treats Alzheimer's and similar brain disease, and actually stimulates the production of new brain cells.

It will interesting to watch the disappearance of all this fear-mongering after we end the fraudulent, freedom-strangling war on marijuana consumers.

Dec 04, 2015
Just another BS disinformation story put out by the government in an attempt to stymie the will of the people. Everyone knows cannabis only works the way God created it, as a symbiosis, you can't take it apart and expect it to work the same. I've been using cannabis for 40 years and have never had or witnessed a bad reaction.

Dec 04, 2015
Pinene has been known for centuries to clear the mind and is also a prominent terpene in cannabis. As well, the cannabinoid CBD is a modulator of THC. All the cannabinoids and terpene's working together are called the Entourage Effect. If you separate them and dose a subject will not have the same effect as they do with the combination of chemicals.

Dec 04, 2015
""This interesting study suggests a commonality between the effects on the brain of the major active ingredient in marijuana and symptoms of schizophrenia,"

I am at a loss so far as to what 'noise' is supposed to mean' ! I'm not a Neurologist, Psychiatrist, or medical professional, but if going back lets say 40 years ago to college days, 'neural noise' would imply to me something like misfiring of neurons across synoptic junctions which would basically leave one scrambled; or offer a good theory for epilepsy. Then of course there is the myelin sheath which could leak.

It would help if the research demonstrated perhaps what they mean by 'noise.'

'Symptoms of Schizophrenia' should also be elaborated on. If suggesting that the psychological affect of THC in providing a euphoria is supposed to be like a Schizophrenic experience, I feel this is misleading and would want to suggest a more complete study based on heavy doses of LSD instead -

Dec 04, 2015
The propaganda continues, first is was based on prohibition opinions, which proposed that marijuana was bad for you in every way and a 'gateway' drug, then it was "we don't know enough, the scientific studies haven't been done", then it was this or that "studies show it cases this or that negative effect", probably based on over dosage or excessive use.

It would be great if the millions of people who have good results with marijuana use with zero negative side effects where considered.

Dec 05, 2015
Of course it causes noise. This is where all of Lady Gaga's music comes from.

Dec 06, 2015
Is that why democrats are nuts over gun control so they can no only sacrifice themselves to slaughter by terrorists WITH smuggled guns, but make it so they can slaughter you too?....They are all stoned stupid on 'mary-jane' to the point they cannot think at all.

Dec 08, 2015
12380 gun this year, mass shootings 311, deaths from "terrorists" 0 . A clear link that all Democrats are stoners. Is the tin foil hat hard to wear at night? Or does it impede communications from the mothership?

Dec 08, 2015
^ should read 12380 gun deaths .

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