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LSD: From Aztec Rituals to CIA Mind Control

This is the first article of the series of posts about most known drugs. Each week, we’ll discuss one, giving you information about their mode of action, observable effects, and quoting accounts of people exposed to the drug.

Lysergic Acid Diethylamide (LSD) was first synthesised in 1938. It was used in psychiatric research to simulate experimental psychosis. US Army and CIA were working on using it for military purposes, and to control the mind of the suspects during interrogation. First conquistadors also describe very similar psychoses caused by consuming ancient Aztec potions, which were thought to be used as a method of contacting the supernatural powers.


A medium dose is 100-200 µg p.o.

Overdosing is problematic because the patient is prone to extensive psychosis and thus is unable to communicate with the researchers normally.

Small change in cells, massive effect on brain

Mode of action

The main hypothesis is that the LSD inhibit the serotonergic cell firing and preserves the up/down regulation of the postsynaptic serotonergic receptors. The neurones producing serotonin are mainly located in the raphe nuclei of the midbrain. Once inhibited, they will affect the locus coeruleus, which in turn will change the noradrenaline signalling for the sympathetic nervous system.
Areas influenced by the locus coeruleus include cerebellum, thalamus, hypothalamus, cerebral cortex and hippocampus. Raphe nuclei will also extend its projections to the brainstem and up into the brain.
It’s almost impossible to imagine how relatively small area in the brain can cause such an extensive effect on all our motor, visual and physiological control panels.


Figure above shows an animation put together by a person supposedly exposed to LSD (Reddit)

Observable effects (selected)

– adapted from (Passie et al., 2008)

  • Illusions
    • Pseudo-hallucination
    • Intensification of colour perception
    • Metamorphosis-like changes in objects and faces
    • Intense (kaleidoscopic or scenic) visual imagery with transforming content
    • Intensification of emotional experience
    • Shortened attention span
    • Unusual inner perception of bodily processes
    • Mystical-type experiences


Accounts of exposed people


From Hofmann’s personal scientific diary: 
“I was forced to interrupt my work in the laboratory […] being affected by a remarkable restlessness, combined with a slight dizziness. At home, I lay down and sank into a not unpleasant intoxicated-like condition, characterised by an extremely stimulated imagination. In a dreamlike state […] I perceived an interrupted stream of fantastic pictures, extraordinary shapes, with intense, kaleidoscopic play of colours”

After a while of repeated exposures

“Fantastic images surged in on me, alternating variegated, opening and closing themselves in circles and spirals, exploding in coloured fountains … Every sound generated a vividly changing image, with its own consistent for and colour”


Another account of similarly acting substance was an ancient Aztec preparation of teonanacatl, a mixture of various spices of Psilocybe mushrooms.
During his bloody conquest, Hernan Cortes described it:

“ there was dancing, there was weeping […] some [of the Aztecs] saw a vision that they would die in war, some saw in a vision that they would be devoured by wild beasts … some saw in a vision that they would become rich and wealthy”

During his travels in South America, Francisco Hernandez accounted that:
“When the priests wanted to commune with their Gods and receive a message from them… they ate this plant and a thousand visions and satanic hallucinations appeared to them”


Eva Mandez, feature in Life magazine, June 1957
“The visions came … they emerged from the centre of the field of vision, opening up as they came, now rushing, now slowly, at a pace that our will choose. They were vivid colour, always harmonious. They began with art motifs, angular such as might decorate carpets or textiles […] courts, arcades, gardens. Then I saw mythological beast driving a regal chariot”



Half of the medium dosage of LSD will be eliminated from the system between 1 and 2 hours after the consumption. The accounts of the people exposed also confirm that the hallucinations end about that time.


Side effects & Addiction
There are no obvious harmful side effects of the drug usage. Although the biochemical receptor model of addiction is highly debatable, even if true, LSD would be unlikely cause any addiction-like behaviour. This doesn’t mean you can’t be addicted to it psychologically.

Long-term usage effects are unclear, but there is some evidence it can cause harm to the memory formation and speed up the development of Alzheimer’s of schizophrenia.

MK Ultra Secret CIA Project


Lastly, the CIA experiments on LSD were a part of a broader project MKUltra. This pseudoscientific endeavour aimed at finding the new methods of extrapolating the information. LSD was a promising gateway to the suspects’ mind but was eventually dismissed as too unpredictable. In the 1960s, the agency developed substances of a greater hallucinogenic effect, and the LSD research was put off altogether.


About the author

Max Brzezicki

Max Brzezicki

Passionate about evidence-based medicine and science, likes slicing meat, crushing rat brains, criminal & public law, foreign languages, rhetoric, history, classical studies and political thought. FNS since 2015.

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19 thoughts on “LSD: From Aztec Rituals to CIA Mind Control

    1. Hi Natalia, thanks for your comment. Can you please point me to where I advertised drug to children. I’ll be happy to address it. Thanks!

      1. Well for starters you didnt say its gonna be for adults only and that should be clearly marked at the beginning of your article furthermore you say all the good things about the drugs and how you can use that and not say anything about wrongs and side effects I have to say I am deeply disappointed by that.

  1. The article may seem bit controversial but I actually enjoyed it. You could talk more about science of it though

    1. Very good point, Michael. I tried to keep it simple, but I’ll think of introducing more of the neaty-gritty of neuropharma in my next piece.

  2. I really don’t understand why people are so obsessed about these drugs??? Get over it! THat’s not too hard, isn’t it????

  3. Actually, I think it really is quite wellexplained. I don’t give a damn about its ethics, it’s just for info. If you ever read what the page is about, you’d understand.

    1. Thanks for your input, Alexander. However, I still think that we should be free to discuss science without violating ethical rules. And I hope this article was just that.

    1. Very good observation, Alistair! I tried to put them together, as the mode of action is very similar and the first reports come from mushroom usage. It was not until 20th century that the actual LSD was synthesised.

  4. I wonder how much more there will be in that series. Will you cover methamfetamine or THC? Have you got a list? Looking forward to other articles lol

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