Pharmakrasis

1From narcocrasis to pharmakrasis

The previous paper in this series, Narcocrasis, asked what a drug does when it is used heavily enough to reset the brain's baseline. This paper asks a prior question: what does a drug do to the senses at all?

McLuhan's most literal claim was that media change "the ratio among our senses." He meant it physiologically, and the first paper in this series, Sensory Syncrasis, argued that he was right to. But media change sense ratios slowly and diffusely, through years of use, and the effects are hard to isolate. Drugs change them within minutes, in measurable ways, and in controlled experiments. If any technology is a sense-ratio technology, a drug is.

McLuhan saw the connection. In his 19692 Playboy interview, he described hallucinogens as “chemical simulations of our electric environment” that "revive senses long atrophied" by print culture. He treated drugs as a symptom of the electric age. This paper treats them as a clearer case of what every medium does.

The central term is pharmakrasis: the configuration of the senses a drug imposes. It joins pharmakon, the Greek word for a drug that is at once remedy and poison, with krasis, the tempered mixture that names the whole series. The double meaning of pharmakon is deliberate. The same chemistry that can fix a configuration into addiction, as Narcocrasis argued, can also loosen one. A drug is never only a poison or only a cure; it is a re-tempering whose direction depends on dose, person and setting.

The paper makes three claims, in order of confidence. First, drug classes produce characteristic, partly measurable changes in the configuration of the senses, which can be mapped onto the five dimensions of sensory syncrasis. Second, those changes can be read as a typology: each class is a recognisable setting, not a random disturbance. Third, when a drug meets a medium, the result is what McLuhan called a hybrid, a new configuration that neither produces alone.

The first claim rests on direct evidence for some drugs and some dimensions. The second is interpretation built on that evidence. The third rests on one strong case and much thinner evidence beyond it. The paper marks which is which throughout. The typology itself, as far as we have found, has not been attempted before.

2What a drug changes: the five dimensions

Sensory Syncrasis proposed that the configuration of the senses has five dimensions. They are the coordinates for everything that follows.

1. 1Sense ratio: how much weight each sense gets when they are combined. A drug that makes music feel more vivid than sight, or that narrows attention onto one target, changes the ratio.
2. 2Overall gain: how strongly all channels are amplified at once, set largely by arousal and the brain's neuromodulators. Stimulants turn it up; sedatives turn it down.
3. 3Integration mode: whether signals from different senses are fused into one experience or kept apart. Psychedelics push toward fusion, sometimes to the point of sounds seeming to have colour. Dissociatives push the other way, pulling the sense of the body apart from the senses of the world.
4. 4Inside–outside balance: how attention is shared between signals from the body and signals from the world. Some drugs turn attention inward to heartbeat and breath; others numb the inside channel.
5. 5Persistence: how long a setting lasts after its cause is gone. For most drugs, the acute configuration lasts hours. For some, the after-effects, whether tolerance, dependence or a window of plasticity, last far longer.

In the vocabulary of predictive processing, these dimensions are aspects of how the brain assigns confidence, or precision, to different signals. Many drugs act directly on the neuromodulators thought to set that confidence: dopamine, noradrenaline, acetylcholine and serotonin. That is part of why drugs are such clean cases. They act on the machinery of the configuration itself.

The framework has a limit worth stating at the start. These five dimensions are a proposal, not an established measurement scheme, and no study has measured all five for any drug. What follows assembles evidence measured for other purposes and reads it through the framework.

3The evidence

Five bodies of controlled evidence anchor the typology. Each is narrow, and together they are the firm ground the rest of the paper builds on.

Time

Time perception is the most directly measured drug effect on the sensorium. In pooled data from placebo-controlled studies of intravenous THC (44 participants), cannabis made people overestimate how much time had passed and cut produced intervals short, as if an internal clock had sped up. The effect was blunted in frequent users (Sewell and colleagues, 2013)3. Psilocybin did something different: it impaired the reproduction of intervals longer than about two and a half seconds and disrupted people's ability to tap in time with a beat (Wittmann and colleagues, 2007)4. One drug speeds the clock; the other loosens the grip on longer spans of time.

Cross-modal blending

Psychedelics are famous for synaesthesia, sounds seen as colours. A systematic review found such reports mostly with serotonergic psychedelics, especially LSD, with sound-to-colour the most common (Luke & Terhune, 2013)5. A careful placebo-controlled study then tested the claim. Under LSD, people did report more synaesthesia-like experiences, but their colour pairings were no more consistent than under placebo, so the experiences did not meet the strict criteria for true synaesthesia (Terhune and colleagues, 2016)6. The accurate claim is weaker and still interesting: psychedelics increase cross-modal blending without producing fixed, genuine synaesthesia.

The body

In the rubber-hand illusion, people come to feel a fake hand as their own when it is stroked in time with their hidden real hand. In a double-blind study of 15 people, ketamine strengthened the illusion and made it persist even when the stroking was out of sync, which normally breaks it (Morgan and colleagues, 2011)7. Ketamine loosens the binding between the body as felt and the body as seen.

Opioids are often assumed to make the body feel warm and pleasant, but the one rigorous test of touch did not support this. In a trial of 49 men, neither morphine nor the opioid blocker naltrexone changed how pleasant touch felt (Løseth and colleagues, 2019). That null result matters for the typology.

Music

The best-documented drug effect on an aesthetic medium is LSD on music. In a placebo-controlled study of 10 people, LSD deepened emotional responses to music, with stronger feelings of wonder, transcendence and tenderness (Kaelen and colleagues, 2015)9. Brain imaging in 12 people found that LSD with music increased communication between the parahippocampal region and visual cortex, and this tracked richer imagery with eyes closed, including autobiographical scenes (Kaelen and colleagues, 2016)10. The samples are small, but the findings are consistent.

Sensory gain

Sedatives turn sensory responses down. In small placebo-controlled studies, benzodiazepines such as lorazepam and alprazolam reduce the brain's electrical responses to sounds (the auditory evoked potentials known as N1 and P2). This is close to a direct measure of lowered overall gain, though the studies are small and this evidence is less firm than the rest of this section.

What the evidence covers

The firm findings cluster in a few places: cannabis and psilocybin on time, ketamine on the body, LSD on music, and, less firmly, sedatives on gain. Much of the rest of what drugs do to the senses is documented in experience reports and clinical observation rather than controlled measurement. The typology in the next section is built on this uneven ground and says so cell by cell.

4A typology of drug classes

The table maps each drug class onto the five dimensions. It is the paper's central construct and its most interpretive one. Each cell carries a grade: strong means controlled human evidence, suggestive means consistent but indirect or small-sample evidence, and weak means experience reports or theory.

Reading the table

Three patterns stand out. The classes differ most on overall gain, where the evidence is strongest. They differ most interestingly on integration mode: psychedelics fuse, dissociatives decouple, and stimulants sharpen selection, three distinct ways of combining the senses. And persistence is where the drug's story continues after the drug is gone, in tolerance, dependence or plasticity.

The table should be read as a map with uneven survey quality. Its value is that it puts very different drugs into one comparable frame, and it shows clearly where measurement is missing: most cells for integration mode and inside–outside balance have never been tested directly.

5Hybrids: when a drug meets a medium

People rarely take drugs in a sensory vacuum. They drink in bars full of music and screens, smoke cannabis in front of a television, take psychedelics with headphones on. In each case a drug sets a configuration of the senses, and a medium then arrives into it. The experience belongs to neither alone. McLuhan's word for this, discussed in the next section, was the hybrid.

The strong case: psychedelics and music

Psychedelic therapy is the one setting where the drug–medium hybrid has been designed on purpose and studied. Sessions are built around carefully chosen music. In a study of 19 people with treatment-resistant depression given psilocybin, the quality of the music experience during the session, not the overall intensity of the drug, predicted how much their depression improved a week later, and it tracked insight and mystical-type experience (Kaelen and colleagues, 2018)12. The authors called music "the hidden therapist."

Together with the earlier LSD studies (section 3), this gives a coherent picture. The drug raises the emotional weight of sound and increases its coupling to visual imagery and memory. The music then lands on that altered configuration and becomes part of what the treatment is. Neither the drug alone nor the music alone produces the effect.

Cannabis, music and the screen

Cannabis users have long reported that music sounds better and films absorb them more deeply. Some evidence fits this. Early EEG work found changes in brain rhythms during music listening after cannabis, leading to the suggestion that cannabis works like a "hearing aid" for music (Fachner, 2002)13, but it studied four people with no control. Recent work has begun to examine the cannabis–music interaction more systematically (Darakjian and colleagues, 2025)14, though controlled studies remain scarce.

In syncrasis terms, the mechanism is plausible. Cannabis raises the weight of sound and detail, loosens associations and speeds the felt passage of time (section 4). A film or a song arriving into that configuration is received with different emphasis, at a different apparent pace, with more associative drift. That is a hybrid in McLuhan's sense. But for television and film specifically, there is almost no controlled research. The cannabis-and-TV hybrid is a widely shared experience and a genuine research gap.

The thin rest

For the other obvious pairings (alcohol and advertising, stimulants and gaming, caffeine and screen work), controlled studies of how the drug changes the experience of the medium barely exist. This paper's claims about them are extensions of the framework, not findings.

Set and setting as the hybrid

The most developed scholarly frame for drug–medium interaction is "set and setting": the idea that a drug's effects depend on the person's mindset and the physical and social environment. Ido Hartogsohn's American Trip (2020)15 traces how the same psychedelics produced very different experiences in different twentieth-century settings, from psychiatric research to the counterculture.

Pharmakrasis reads set and setting in a particular way. Drug research often treats setting as a confound to control. Here it is half of the hybrid: the medium the drug meets. The 1960s understood this practically. Light shows, the 1966 Trips Festival in San Francisco, the art collective USCO and Stewart Brand's multimedia events deliberately combined psychedelics with projected images, sound and environment. McLuhan's ideas were widely discussed in that scene. It was, in effect, an uncontrolled experiment in drug–medium hybrids at the scale of a culture.

6McLuhan on drugs, hybrids and hot and cool

Hybrid energy

Chapter 5 of Understanding Media, "Hybrid Energy: Les Liaisons Dangereuses," argues that the most revealing moments in media history come when two media meet:

“The hybrid or the meeting of two media is a moment of truth and revelation from which new form is born.”

He adds that such a meeting is “a moment of freedom and release from the ordinary trance and numbness imposed by them on our senses.” McLuhan meant media meeting media, such as radio meeting film to make the talkie. But the logic applies directly to a drug meeting a medium. Each sets a configuration of the senses; together they produce a third. And McLuhan's suggestion that the hybrid breaks the usual numbness fits the experience reports of people who say a familiar song or film became newly strange and vivid under a drug.

Drugs and the electric environment

In his 1969 Playboy interview, McLuhan linked drug use directly to electric media:

“The upsurge in drug taking is intimately related to the impact of the electric media.”

He described LSD as “a way of miming the invisible electronic world” that “releases a person from acquired verbal and visual habits,” and hallucinogens as “chemical simulations of our electric environment” that “revive senses long atrophied by the overwhelmingly visual orientation of the mechanical culture.” Asked whether he had taken LSD himself, he said no: “I'm an observer in these matters, not a participant.”

McLuhan's claim was historical and cultural: the electric environment made people hungry for a total, all-at-once sensory involvement that drugs could provide. Pharmakrasis makes a narrower and more physiological claim. Whatever the cultural reasons people take them, drugs do in hours what McLuhan said media do over years.

Hot and cool

McLuhan divided media into "hot," which fill one sense with high-definition information and leave little for the audience to complete (print, radio, film), and "cool," which offer low definition and demand participation (speech, telephone, television as he saw it in the 1960s). He associated psychedelics and electric media with the cool, participatory, "audile-tactile" sensibility, against the hot visual culture of print.

The typology suggests that drugs can be placed on the same axis, though no one has done so formally. Stimulants, which narrow attention and raise gain, look hot. Psychedelics and cannabis, which loosen associations and invite the experiencer to fill in, look cool. If that holds, a drug–medium hybrid would combine two temperatures, and some pairings, a cool drug with a hot medium or the reverse, might produce the vividness McLuhan attributed to the hybrid. This is speculation on the paper's part, offered as one of the more interesting directions the framework opens.

A meeting in 1966

Timothy Leary later said that his slogan "Turn on, tune in, drop out" grew out of a 1966 lunch with McLuhan, who advised him that the psychedelic movement needed catchy, advertising-style messaging. Leary told the story in his memoir Flashbacks (1983)17. The anecdote is widely repeated, but it comes from Leary alone and should be treated as his account rather than an established fact. If true, it is a fitting detail: the most famous slogan of the drug culture shaped by the theorist of media.

7Nearest neighbours and what is new

The idea that drugs and media belong in the same conversation is not new. Several thinkers have put them side by side, each from a different direction.

Ido Hartogsohn is the closest. American Trip (2020)15 shows that psychedelic effects are shaped by their cultural and sensory settings, and his wider work treats psychedelics as media in their own right. With Vudka, he reads digital media as narcotic through McLuhan's idea of numbness (Hartogsohn & Vudka, 202316, Transcultural Psychiatry). That work runs the comparison from media to drugs at the level of culture and discourse.

Jacques Derrida, in "Plato's Pharmacy," drew out the double meaning of pharmakon: remedy and poison at once, and in Plato's dialogue, a word for writing itself. In "The Rhetoric of Drugs" (1989)18, he examined how the very category of "drugs" is constructed. Bernard Stiegler extended the pharmakon to all technology: every technical system is both poison and cure.

Literary and cultural historians have traced writers' relationships with drugs: Marcus Boon in The Road of Excess (2002)20, Sadie Plant in Writing on Drugs (1999), and Avital Ronell in Crack Wars (1992).

What none of these does is the thing this paper attempts: to treat drug classes as specific configurations of the senses and map them, dimension by dimension, onto measured perceptual effects. Hartogsohn supplies the frame of drugs as media and setting as decisive. Derrida and Stiegler supply the pharmakon. The literary historians supply the cultural record. Pharmakrasis adds three things to that: a typology of drug classes across five sensory dimensions, a grounding of that typology in the neuroscience of precision and neuromodulation, and a reading of drug–medium combinations as McLuhan's hybrids. As far as we have found, those three are new.

8Objections and replies

"The typology over-reads thin evidence." Partly conceded. Only a few cells rest on controlled human studies: cannabis and psilocybin on time, ketamine on body ownership and LSD on music, with weaker evidence for sedatives on sensory gain. That is why every cell is graded. The typology is offered as a map that organises what is known and exposes what is not.

"Drugs act on the brain directly; media act through the senses. They are different kinds of thing." True of the route, not of the result. McLuhan's claim concerns the configuration of the senses a technology leaves behind, and both drugs and media end in changes to how the brain weights and combines its channels. The paper does not claim a drug is a medium in every respect. It uses drugs as a magnified, faster case of the change McLuhan attributed to media, and the hybrid section is precisely about what happens when the two routes meet.

"Drugs as media is already Hartogsohn's idea." Hartogsohn is the nearest neighbour and is credited as such (section 7). The novelty lies elsewhere: the five-dimensional typology, its grounding in the neuroscience of precision, and the reading of drug–medium combinations as hybrids.

"Psychedelic synaesthesia isn't real synaesthesia." Conceded, on the best evidence (Terhune and colleagues, 2016)6. The paper claims only increased cross-modal blending and synaesthesia-like experience, which is what the evidence supports.

"Set and setting make drug-specific signatures impossible to isolate." Set and setting certainly shape outcomes. But that cuts in favour of the hybrid reading rather than against the typology. A drug sets a characteristic configuration; the setting is the medium that meets it. Both are real, and the experience is their combination.

"Many effects are just general arousal." For some cells, especially overall gain, that may be true. But arousal alone does not explain why psychedelics fuse the senses while dissociatives pull them apart, or why cannabis and psilocybin distort time in different ways. Those differences are what make a typology worth drawing.

"Hot and cool for drugs is speculation." It is, and section 6 labels it as such. It is included because it is the most direct bridge between McLuhan's own categories and the typology.

"This could read as endorsing drug use." It is not an endorsement. The paper describes what drugs do to perception because that is the clearest available evidence for McLuhan's claim about sense ratios. Several of the drugs discussed carry serious risks, and the companion paper, Narcocrasis, is about how drug use becomes dependence.

9Conclusion

McLuhan's claim that media change the ratio among our senses has always been hard to see, because media do it slowly and everywhere at once. Drugs do it quickly and in isolation. That makes them the clearest available demonstration that a technology can re-temper the senses, and a way of seeing, at higher magnification, what McLuhan said every medium does.

Pharmakrasis names that re-tempering. Each drug class sets a recognisable configuration: stimulants raise gain and narrow selection, sedatives lower gain, psychedelics fuse the senses, dissociatives decouple the body, cannabis reshapes time and the weight of sound. The evidence for these settings is strong in a few places and suggestive in most. The typology makes that unevenness visible rather than hiding it.

The pharmakon sits at the centre. The same chemistry that, used heavily, fixes a configuration into narcocrasis can, in the right dose and setting, loosen it. Which way it goes depends on the molecule, but also on dose, on the person and on the medium the drug meets. That is the hybrid McLuhan described, and it is why the setting of a drug is not background but half the event.

Several questions remain open. Can a drug class be given a stable place on McLuhan's hot–cool axis, or does that always depend on the setting? Is integration mode one dimension or several, given that fusing the senses, binding the body and blending associations may be different processes? Which of the typology's differences are specific to each drug, and which reflect arousal in general? And when a familiar film or song becomes strange and vivid under a drug, is that McLuhan's “release from the ordinary trance and numbness” of a medium, an anti-environment produced chemically? If so, the drug–medium hybrid is not only a pleasure or a risk. It is one of the few ways a person can briefly perceive the medium they live inside.

References

1. 1McLuhan (1964), Understanding Media, ch. 5 "Hybrid Energy: Les Liaisons Dangereuses"
2. 2McLuhan (1969), Playboy interview
3. 3Sewell et al. (2013), Psychopharmacology 226(2): 401–413 (pooled analysis)
4. 4Wittmann et al. (2007), Journal of Psychopharmacology 21(1): 50–64
5. 5Luke & Terhune (2013), Frontiers in Psychology 4: 753
6. 6Terhune et al. (2016), Neuropsychologia 88: 28–34
7. 7Morgan et al. (2011), Biological Psychiatry 69(1): 35–41
8. 8Løseth, Eikemo & Leknes (2019), Social Cognitive and Affective Neuroscience 14(4): 411–422
9. 9Kaelen et al. (2015), Psychopharmacology 232(19): 3607–3614
10. 10Kaelen et al. (2016), European Neuropsychopharmacology 26(7): 1099–1109
11. 11Benzodiazepine auditory evoked-potential studies (lorazepam, alprazolam)
12. 12Kaelen et al. (2018), The hidden therapist, Psychopharmacology 235(2): 505–519
13. 13Fachner (2002), Journal of Cannabis Therapeutics 2(2): 3–36
14. 14Darakjian et al. (2025), cannabis and music, Annals of the New York Academy of Sciences
15. 15Hartogsohn (2020), American Trip, MIT Press
16. 16Hartogsohn & Vudka (2023), Transcultural Psychiatry 60(4): 651–661
17. 17Leary (1983), Flashbacks
18. 18Derrida, "Plato's Pharmacy" (1972); "The Rhetoric of Drugs" (1989)
19. 19Stiegler, pharmacology of technology (e.g., What Makes Life Worth Living, 2013)
20. 20Boon (2002), The Road of Excess; Plant (1999), Writing on Drugs; Ronell (1992), Crack Wars