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The Psychedelic Brain

Alex Hansen's picture

Psychoactive drugs have gained widespread popularity over the years. Growing acceptance has occurred amongst the young with in the urban and suburban societies. In fact, colleges and high schools appear to be breeding grounds for this growing substance abuse. The most popular of such drugs is marijuana as it is regarded as the least harmful and least costly of the psychoactive drugs. Therefore, this lack of cost restriction for marijuana implies easier access amongst the lower class in comparison to other stronger hallucinogens such as lysergic acid diethylamide. This widespread popularity is evident by the observation that millions of Americans have once tried marijuana. While other drugs do not maintain the same pervasive reputation, their usage remains pertinent. For example, Dr. Timothy Leary claims that there were one hundred thousand regular LSD users, one single experience. It is hypothesized that the increase in interest and usage of the internet and World Wide Web along with a heightened rave and trance culture based in an interest of exploring the conscious and unconscious mind has greatly contributed to this problematic drug growth. As a result, the effects of such drugs have become of increasing concern for such chemicals are foreign to the body and produce detrimental effects.

The nervous system in particular is greatly impacted by psychoactive drugs. In turn, such boasts drastic implications as the nervous system is responsible for relaying messages back and forth within the body.  This complex system consists of the central nervous system and the peripheral nervous systems, the central nervous system is the larger of the two and is comprised of the brain and spinal cord. The main function of the central nervous system is to receive information from the body and send out instructions, whereas the peripheral nervous system sends messages from the brain to the remai nder of the body  both indicative of the input/output mechanism. Therefore, as the brain is related to behavior, such is implicative of the relationship between the central nervous system and brain and behavior.

One such mechanism which affects behavior is drugs. Specifically, psychoactive drugs, chemicals that act in the central nervous system, infringe upon the function of the brain. These brain complications include ones related to perception, consciousness, thought, emotions, mood, and behavior.  Clearly, psychoactive drugs induce differing effects on the body depending upon classification. These drugs are commonly subdivided into four categories: antipsychotics, depressants, stimulants and hallucinogens, of which hallucinogens are further divided into psychedelics, dissociatives, and deliriants. Deliriants are defined as substances which cause a temporary state of mental confusion and fluctuating consciousness by anxiety, disorientation, hallucinations, delusions and incoherent speech.  Dissociatives are drugs which reduce, or block, signals to the conscious mind from other parts of the brain, typically, but not necessarily, limited to the physical senses. Lastly, psychedelics are psychoactive drugs whose primary action is to alter the thought processes of the brain. Thus, many of the widely used illegal drugs can be placed into one of the three categories. For example, phenylcyclohexylpiperidine, ketamine, dextromethorphan, nitrous oxide, salvia divinorum, and muscimol are all dissociatives. In comparison, deadly nightshade, mandrake, henbane, antihistamine diphenhydramine, antiemetic dimenhydrinate, and datura are known as deliriants.

Such varying drug classifications withi n the hallucinogenic psychoactive drugs infer differences amongst their individual effects. Primarily, deliriants are considered true hallucinogens th nonexistent people. Therefore, the hallucinogenic quality of deliriants initiates immediate effects such as sleepwalking, for the abuser is unable to recall their experience after taking the substance. Deliriants such as diphenhydramine exhibit direct effects on the central nervous system as they are classified as anticholinergic agents, and thus reduce the affects of ac etylcholine in the nervous system. An example of acetylcholine function lies in synaptic plasticity. Common central nervous system malfunctioning includes agitation, respiratory depression, short-term memory loss, incoherent speech, photophobia, unusual sensitivity to stimuli, inability to sustain a train of thought, etc. An overdose of a deliriant causes additional side effects including dehydration and mydriasis, while the most severe outcome of this drug is death due to its high level of toxicity.

Similarly, while deliriants appear to lead to a loss of consciousness , dissociatives induce conscious dreaming, more commonly known as lucid dreaming, elicit states of mind due to sensory deprivation. Dissociatives also play a unique role as a central nervous system depressant lowering ones heart rate and/or respiration and oxygen intake, ultimately causing death. Specific long term use of dissociatives, such as ketamine and phenylcyclohexylpiperidine, has even been claimed to induce Olneys lesions known as NMDA Receptor Antagonist Neurotoxicity,  a form of brain damage. Such damage pertains to the vacuoles in the posterior cingulated cortex and retrosplenial cortex of the brain and causes an increase in microglia and heat-shock protein 70 concentrations. Other damages to the brain include hypertension, a toxic acute brain syndrome manifested by disorientation of consciousness and convulsions. Thus, overdosing on deliriants and dissociatives is extremely caustic, while overdosing on psychedelics is extremely rare due to the non-toxicity quality of these drugs.

Common psychedelic hallucinogens include lysergic acid diethylamide (LSD), psilocybin, mescaline, dimethyltryptamine, 4-methyl-2,5-dimethoxyamphetamine, San Pedro cactus, peyote, and even cannabis. Their effects are extremely dependent upon the actual drug, the dosage, and the environment as they disable filters of the mind. Such effects range from distortions of a single sense such as auditory hallucinations, to effects on cognition, to empathogenic emotional and social effects. However, one common property, especially amongst perception-altering psychedelics, is the ability to act on the 5HT-2A receptor, a serotonin receptor of the brain.

Lysergic acid diethylamide is a primal example of a psychedelic drug associated with serotonin activity in the brain. The specific effects of LSD usage include impaired intellectual ability, lowered IQ, an inability to concentrate, breakdown of ego functioning, and feelings characterized by emptiness, loneliness an d isolation. Such is also characteristic of schizophrenia, and thus has alluded to similarities between LSD and the mental disorder, ultimately proposing the hypothesis that LSD has the ability to cause schizophrenia. With such, the relationship between LSD and the brain is essential in understanding the chemical's mechanisms. Specifically, the drug is often considered to inhibit the production of serotonin in brain cells - a monoamine neurotransmitter synthesized in serotonergic neurons in the central nervous system associated with perception and memory. Further evidence supporting such a relationship includes the data that illustrates that drugs which stimulate serotonin production directly impede on the effects of the psychedelic. Therefore, it can be hypothesized that LSD interacts with the 5-hydroxytryptamine (serotonin) receptors in the brain, ultimately lowering the concentrations of brain serotonin. Research indicated that lysergic acid diethylamine reduced the turnover rate of brain 5-hydroxytryptamine in rats rate of discharge of raphe nuclei neurons located in the area of reticular formation containing most of the serotonergic cell bodies. In addition, LSD antagonizes the potentiating action of reserpine, which is the chemical typically involved with releasing large amounts of serotonin. Therefore, it is evident that lysergic acid diethylamine essentially lowers the levels of serotonin in the brain through various functions.

Overall, hallucinogenic drugs are directly involved with the central nervous system, directly involved with the input and output system. Therefore, the psychoactive drugs' relationship with neurons in turn indicates their ability to induce permanent damage. It has even been shown that psychedelic substances cause chromosome breakage, which not only affects the user, but ultimately affects and unborn child. In order to preserve a healthy brain, a healthy nervous system and healthy children, psychoactive drugs need to be avoided. However, ceasing usage of the drugs d oes not include halting research regarding the numerous drugs. The relationship that exists between substances and the brain including the neurons of the nervous system, can be advantageously exploited. If we are able to better understand the mechanisms behind these drugs and their hallucinogenic effects, their effect on the brain, advancements could be made. As such, could gain the ability to understand the role of the unconscious, and more importantly, better our understanding of neuronal functioning, which in turn could lead to various cures and promote health.


[ed. note: Bibliography/ End Notes was damaged in backup /restore operation. Will be re-built.]

Alicia Ebbitt, The Effects of Hallucinogenic Drugs on The Brain neuro98/202s98-paper1/Ebbitt.html>

Burton M. Altura, �Phencyclidine, Lysergic Acid Die thylamide, and Mescaline: Cerebral Artery Spasms and Hallucinogenic Activity�Hallucinogen s�MBC 3320 Acetylcholine,� /MBC3320/acetylcholine.htm >

Michael Fichman, �LSD- Origins and Neurobiological Implications� html>� M.J. Farabee, �The Nevous System,� BioBookNERVhtml >�

\nParkhurs t A. Shore, Stanley L. Silver andBernard B. Brodie, �Interaction of Reserpine, Serotonin, and Lysergic Acid Diethylamide in Brain< /a>� Costa, �Lysergic Acid Diethylamide: Role in Conversion of Plasma Tryp tophan to Brain Serotonin (5-Hydroxytryptamine),� 8) Vol. 68, No. 3\n

[2] Wikipedia Encyclopedia, s.v. �Psychedelics, dissociatives and del iriants.� tle=\"_ftn3\">[3] Wikipedia Encyclopedia, s.v. �Nevous system.� Text\">[4] M.J. Farabee, � The Nevous System,� p>\n

[5] The Body: The complete HIV/AIDS Resource,� pinfg7pyscho/ drugbkix.html >

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Wikipedia Encyclopedia, s.v. Psychedelics, dissociatives and deliriants

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Dr. Ngoc 's picture

Muffet Hemingway-I think Mariel is making assumptions

Joan (Muffet) Hemingway has been interviewed herself about what she thinks escalated her mental illness and she was quick to say that her drink was dosed with it unbeknownst to her, when she was 16. Mariel seems to believe that Muffet ran out to San Francisco in her teens and dropped acid on a regular basis. I would tend to believe the person it happened to. Mariel is much younger than Muffet and is probably going on years of speculation by her family - the majority of whom were (since I think they're all dead except for her and Muffet) drunks and, in Margaux's case, an epileptic who abused various drugs and alcohol as well. If Muffet says that she was heavily dosed once, and without knowledge of it, I - having had the same thing happen to me - but at 19 - would tend to believe Joan. It's a very, very sad story, and the Hemingways are a tragic family. Mariel is doing her best, holistically, to "run from crazy," and for the most part I think she's beating it. I hope the cycle of tragedy in her family ends soon. - Dr. Ngoc

Kris Bradford's picture

Great read. I think the

Great read. I think the important word is "abuse", as long they don't abuse it and has no long term side effects it should be OK, if not they should warn them. I tried Dimethocaine recently. Some elements are definetly cocaine like, a certain mental clarity, crispness, fatigue relief, rebound stimulant. To me it seems just slightly less potent or about the same as street cocaine but it lasts like 3 hours. It works pretty good for my toothaches which are pretty severe.

Serendip Visitor's picture

Research thus far does not

Research thus far does not say that people with a genetic disposition towards schizophrenia will be triggered, it says people who were predisposed to develop the illness may have an earlier onset as result of psychedelic use. By definition these persons were going to develop schizophrenia anyway.

An important point to be noted is that scientists have not even conclusively proven schizophrenia is a genetic disorder. To suggest that perfectly normal people who would have never developed the disease have some time bomb gene triggered only by LSD is misleading.

And we all agree that misuse of psychedelics can pose significant risks.

Serendip Visitor's picture

Some factual corrections: Syd

Some factual corrections:

Syd Barrett was not a one-time acid casualty. By choice he took enormous amounts of LSD for several years.

The song Dr Robert was about an American doctor who was known for prescribing amphetamines to his patients.

The Beatles were spiked with LSD by their dentist, but reported they seemed to find value in the experience that they continued to use it (John and George heavily).

However, whether or not it is an inherently harmful or useful substance is independent of the issue of psychologically unprepared people receiving high doses without their knowledge. Drugging someone without his/her consent is an ethical violation and the worst environment for any potential safe or beneficial use. Individuals experiences on psychedelics are dependent on set and setting and the circumstances you described are unarguably dangerous.

Serendip Visitor's picture



I quote all of you wonderful people for truth.

I was going to pick it apart further, there are a few areas, but that's basically good enough.

It's really too vague, contrived, and flat out pseudoscience, , BS and rehashing of words, for me to waste my time picking apart further. there would have to be some truth there, you might as well toss this whole article. I intend no offense to you Alex.

your communication also could use some improvement, you build up with all these words, but they are not in a commonly used context. it's even worse when the logic is fallacious and misplaced.

You'd be better off studying mystical experiences, in which you don't have this bias. however you may have another bias, or several. we all have our subjectivities, to the supposed objectivity.

Anonymous's picture

"Other damages to the brain

"Other damages to the brain include hypertension, a toxic acute brain syndrome manifested by disorientation of consciousness and convulsions."

hypertension - "a. elevation of the blood pressure, esp. the diastolic pressure.
b. an arterial disease characterized by this condition" (

Here, you take the liberty of creating your own "toxic acute brain syndromes;" in reality, hypertension is simply raised blood pressure. This does result (usually insignificantly, except in the case of overdose) from MDMA usage, but the opposite actually results from Cannabis use (the blood pressure is lowered). The picture is more obscure in the case of your true psychedelics - LSD, Psilocin, and Mescaline, etc. - but there is no way that any increase in blood pressure from use of these drugs amounts to any brain damage...(as far as I am aware, the only brain damage that could be done would be caused by a stroke!) Hypertension = a "toxic acute brain sydrome"? Come on, this is offensive!

Also, you misidentify your drug pharmacology: "Common psychedelic hallucinogens include lysergic acid diethylamide (LSD), psilocybin, mescaline, dimethyltryptamine, 4-methyl-2,5-dimethoxyamphetamine, San Pedro cactus, peyote, and even cannabis...However, one common property, especially amongst perception-altering psychedelics, is the ability to act on the 5HT-2A receptor, a serotonin receptor of the brain." You may not be aware, but MDMA's action on the brain is very different and incomparable to both cannabis or the true psychedelics mentioned above. MDMA results in a massive release of serotonin into the synapses, while at the same time, it acts as a SSRI (serotonin reuptake inhibitor). As far as I know (and I am quite sure), MDMA has no specific effects on the 5-HT2a receptor, which is consequently why MDMA produces no actual visuals or hallucinations in the same sense that LSD, Psilo., or Mescal. do. You should also research the pharmacology of THC (cannabis) because it certainly doesn't produce its effects through the 5-HT2a receptor.

All in all, I found this article to be quite offensive. As anonymous above said, it seemed clearly biased towards the anti-drug side. It's factual validity is highly disputable in many places, and it is absolutely incorrect in others.

Anonymous's picture

Amen to that

After extensive readings of authors such as Stanislav Grof and John C. Lily (amongst many others) I can also back up what anonymous said above. The original article is biased and fraught with supercilious statements which indicate a rather ill considered and unbalanced view of entheogens.

Please take the time to consider the inreasingly available literature on the topic from credible scientists and anthropological academics alike who have backed up the more holistic view of psychoactive substances using cross-cultural and cross-temporal evidence.


Anonymous's picture

Your article is fraught with

The psychotomimmetic model of LSD and mescaline "Model Schizophrenia" was abandoned in the late 1950s when researchers like Humphry Osmond, Abraham Hoffer and Sidney Cohen discovered the importance of Set and Setting when using hallucinogens. The idea proper hallucinogens mimic schizophrenia was the result of researchers putting subjects in sterile white rooms and telling them they were going to be temporarily insane, thus shaping expectation and setting.

The idea that LSD can cause schizophrenia has also been debunked knowledge that many people who became schizophrenic after LSD use already had a heritable liklihood of the disease or exhibited symptoms. The concensus today is that LSD can trigger latent schizophrenia in persons who were most likely going to develop it anyway.

As for your comments about chromosome breakage and LSD, these claims have been discredited since the late 1960s.

Additionally, no researcher has ever produced concrete evidence of organic brain damage as the result of hallucinogen use. In the 50s and 60s LSD was administered to tens of thousands of people without a single record brain or nervous system damage. In fact recently Dr. John Halpern of the Harvard School of medicine showed that Native Americans who had consumed peyote more than 100 times showed no cognitive deficits, and were in fact, better psychologically adjusted than non-peyote users.

Lastly I have to add, if it wasn't obvious by the lack of factual accountability in your article your extreme and unscientific bias against hallucinogens is patently obvious when you state only the negative effects and then generalize them as if they were typical. This is like saying the effects of Prozac are nausea, dizziness, decreased sex drive and drowsiness. Why would anyone take it? You write "The specific effects of LSD usage include impaired intellectual ability, lowered IQ, an inability to concentrate, breakdown of ego functioning, and feelings characterized by emptiness, loneliness an d isolation" Are you speaking of accute effects, long term effects? If LSD is so horrible, you would have to question why anyone would be motivated to take it all? If hallucinogen use is a frightening epidemic as you say, you might want to question what the appeal of these drugs are.

Many people will also tell you than specific effects of LSD usage include self-trancedence, insight, heightened positive attitude, existential adjustment, higher levels empathy, better aesthetic appreciation and increased intellectual ability. Indeed, to evaluate the meaning of hallucinogen use in our society you might want to investigate if the drugs actually are having a detrimental effect, or perhaps if they are having a positive influence. I can say this, one is much more apt to get into a fight at bar than at a rave, and more likely to get a hug or backrub at a rave than a bar.

Indeed, there is a renewel of legitimate research into using hallucinogens and MDMA in medicinal and psychiatric context. I would suggest to take a look here or do a search of peer reviewed journals.

Scott Rossi's picture

LSD and schizophrenia


I saw your post on this site, and when I read it, it began to make me sick. I will type these three names into my reply: Joan Hemingway, Syd Barrett of the music Pink Floyd, and Peter Green of Fleetwood Mac. They all suffered from mental illness as a direct result of having had their drinks laced with LSD, unbeknownst to them. As a result of having a "bad trip", for the rest of their lives they lived with schizophrenia and mental illness. You seem to minimize the notion that LSD can cause schizophrenia, but I offer these three cases. Whether or not they were genetically susceptible to getting the illness anyway is a side note. LSD triggered it, and they suffered as a result. I would appreciate any comment to this reply.


Anonymous's picture

You're using a Hemingway as

You're using a Hemingway as an example? Is there a family in the history of the world with a larger history of mental illness than them? I seriously doubt it.

And the response to any example of psychedelic triggered mental problems is the same: if a bad psychedelic experience hadn't triggered it, some other traumatic experience would have.

Of course none of this matters to you. You're a person so bent on manipulating opinion in your favor that facts clearly are no longer relevant to your ultimate goal. I mean how long has the chromosome thing been debunked? Even if you aren't blatantly lying you're always two steps away from the shaky classical half truths of the drug war. (Terms like flashback.)

Enjoy your delusional world of pure fantasy that the mentally ill and heavily intoxicated could still only dream of.

s.k.'s picture

a bit defensive, no?

>>"And the response to any example of psychedelic triggered mental problems is the same: if a bad psychedelic experience hadn't triggered it, some other traumatic experience would have."

Oh really? So you admit that a person can have a genetic disposition to schizophrenia. And you admit that LSD can trigger it. So then you conclude that if LSD had not triggered it, SOMETHING ELSE WOULD HAVE?

How in the world do you come to that conclusion? What other events, pray tell, are you thinking may "trigger it?" What if the person never has a particularly "traumatic event" in the span of years that schizophrenia usually manifests? Isn't it true that schizophrenia can run in a family and NOT affect many who carry the genes?

And even if you believed that "something else" would have triggered it, how can you know that it's true? Wanna give us a reference to that?

All I can say about all of the responses to this column is "Thou protesteth too much." The extremes that you guys will go to to defend your love of psychedelics is laughable. I'm not even against people using the stuff. I just think it's funny that you have to chuck all reason--for whatever reason--to defend your use.

Serendip Visitor's picture

Action and reaction

There are people protesting too much on both sides of the debate, most of what has been written here in defense of psychedelics is very tame and quite right, though spiking anyone with a psychedelic is morally reprehensible and unacceptable. Protesting too much on the defensive side is a reaction to protesting too much on the side of the state, whose only interest is to defend prohibition no matter how much bad science, bent science, and long debunked myths are needed to persuade people these chemicals are worthless and outright destructive.

There are real dangers to psychedelics, but they do not involve any toxicity or chromosomal damage, they are psychological dangers; and they can be avoided with the right education and regulation. Aside from this psychedelics can be useful, for a host of clinical reasons, for self exploration and to promote greater appreciation of life, tolerance/compassion/altruism. Also, if you decide to throw out rationality with the experience there is a risk you could start believing in unicorns. The experience needs to be "decoded" to get insight generally, and then it's really you meditating on it afterwards and coming to new ideas about the world, it works though.

I understand your flare up, but there are rational arguments in defense of psychedelics, and I think they outweigh those for the current prohibition we have (people who don't know what they're doing getting hurt, because everything is available on the black market).
Also I doubt anyone here can do anything more than speculate as to whether one can have a genetic disposition to schizophrenia, if the jury is out in the medical community.

Scott's picture

Misuse of LSD is the problem.

My point being is that Joan Hemingway never asked to use LSD it was put in her drink unknowingly when she was 16. The result was that it triggered schizophrenia and she had it for the rest of her life. The same happened with Peter Green and I believe with Syd Barrett, and in all three it triggered mental illness. All I'm saying is that LSD can be dangerous when misused. Have you ever heard of the Beatles song "Dr. Robert" on their album Revolver? Its based on the true story. John Lennon and George Harrison and their wives were invited for tea by their dentist around 1966. They never knew it till they began feeling the effects but their tea was laced with LSD put there by their dentist. The experience they had moments after lasted some hours. It freaked them out. Its the misuse of LSD, like anything, that bothers me. It can be dangerous.