Hegemony; false consciousness; propaganda; biopower. These words, and others like them, denote a space where studies of power intersect with studies of the brain. All studies in the humanities have a psychological dimension. Studies of power, in particular, are laced with assumptions about how the brain works. So what would the study of power in human societies look like if we approached it through the latest research on the brain? If we accept the idea that the brain itself is (in part) a cultural construct, instead of a living fossil composed of hard-wired patterns of stimulus and response, would it be possible to write a history of how changing regimes of power over the last several thousand years emerged in tandem with changes in aggregate neurobiological states?

The history sketched in this article begins with the observation that all human societies are marked by an array of mechanisms that affect brain states. These mechanisms include behaviors such as sex, long-distance running, or spousal abuse; cultural practices such as reading or listening to music; and a considerable range of drugs or psychopharmacological substances.^[151] These are all psychotropic mechanisms. If experienced continuously by an individual, psychotropic mechanisms can create dependencies or addictions. They can numb or amplify the signals that pass across receptors in the brain and even generate new neural maps. If psychotropic mechanisms are distributed widely enough across a sub-population, they can, in theory, alter or transform the aggregate brain, creating generalized states or conditions in whole groups, not just individuals. The brain states would have the appearance of being hard-wired without being genetic.

Brain states associated with stress are already known to have political consequences in primate societies, and it has been suggested that they also have this effect in human societies. Since the very mechanisms that generate neurobiological states are themselves delivered by political and/or economic systems, we can suppose the existence of feedback mechanisms linking political conditions and neurobiological states. These feedbacks may operate at a level below that of full intentionality on the part of political operatives. Regardless, the effects could be significant, and the possibility deserves a place in our analyses of power.

The argument sketched above is not new. Although recent developments in neuroscience have offered new grounds on which to elaborate the argument, other observers of the human condition have arrived at a similar intuition. The argument was prefigured most notably by Aldous Huxley in his Brave New World (1932) and by George Orwell in Nineteen Eighty-Four (1949). These two books, published seventeen years apart, offer competing images of the dystopian nightmare that might be human fate. Both authors shared the basic intuition that cultural practices have drug-like effects and that political cultures can therefore be organized around the strategic manipulation of the human nervous system. In this essay, I will offer a preliminary case study illustrating how a more general (and less paranoid) version of this argument might apply to a specific historical case: that of Europe over the past millennium or so.^[152] To introduce the contours of the argument, however, let us look at the Huxley-Orwell model, a strong version of the basic argument that neurobiological states have political implications.

Orwell wrote as a horrified observer of the rise of modern public relations. The field and technique owe much to the figure of Edward Bernays, a nephew of Sigmund Freud who is often called the father of modern advertising. As Bernays explained in his 1928 work Propaganda, “We are governed, our minds molded, our tastes formed, our ideas suggested, largely by men we have never heard of. . . It is they who pull the wires which control the public mind, who harness old social forces and contrive new ways to bind and guide the world."^[153] From this came Orwell’s interest in the way languages and frames can twist and bend our ability to reason. But Orwell’s fictional city of Oceania was also a world of constant, never-ending stress visited on the body and the nervous system. In a manner reminiscent of Jeremy Bentham’s perfect prison, which he called the Panopticon, all citizens of Oceania are supervised by two-way telescreens and live in constant fear of the thought police. The weekly Hate exercises serve to whip up and channel aggressive sentiments. The total suppression of sexual desire (the torturer O’Brien declares at one point, “we shall abolish the orgasm”^[154]) is designed to channel all bodily feelings toward these exercises and simultaneously eliminate one of the many mechanisms that people use to relieve stress.

Huxley’s model of totalitarianism worked in an entirely different way. The psychological state generated in the Brave New World was not one of stress, but one of pleasure. Commenting on Orwell’s Nineteen Eighty-Four a decade after its publication, Huxley wrote: “government through terror works on the whole less well than government through the non-violent manip­ulation. . .of the thoughts and feelings of individual men, women and children.”^[155]Brave New World explores a nearly insoluble philosophical dilemma: if people are content in their own subjection, is it still subjection? The division of labor in the Brave New World operates by means of child conditioning. From the moment of (artificial) conception, the members of each of the five major castes are genetically manipulated to suit their allotted social condition. Infants destined to be workers are conditioned in Pavlovian ways to resist the allure of flowers, books, and especially mothers. Children are further conditioned through hypnopaedia—constant audio messages played during sleep. As adults, the citizens of the Brave New World are subjected to an additional day-to-day conditioning through free distribution of an opiate called "soma." Soma, we learn, has "all the advantages of Christianity and alcohol; none of their defects."^[156] Huxley, here, was alluding to Karl Marx’s famous passage: “Religion is the sigh of the oppressed creature, the heart of a heartless world as it is the spirit of a spiritless situation. It is the opium of the people.”^[157] Religion, in Marx’s model, is a cultural opiate, an institution or practice that can have a soothing, opiate-like effect on the body. In Brave New World, Huxley turned Marx on his head: the opiate itself has become the religion of the people. A marvelous scene in Chapter Five, a parody of the eucharistic ceremony, plays on a fortuitous pun: soma is the Vedic word for a south Asian opiate, but in Greek it also means “body.”

The denizens of the Brave New World are addicted to soma. They pop several pills each day and never experience the dopamine withdrawal that makes Ecstasy and other equivalents so dangerous. But they are also both stimulated and subdued by the endless recreations of their consumer paradise: the games, the dances, travel, the sensuous, perfumed showers, the endless rounds of sex, all of them opiates or stimulants, albeit of different kinds. As Richard Posner has pointed out, Brave New World was written “in the depths of a world depression that Keynes was teaching had resulted from insufficient consumer demand and could be cured only by aggressive government intervention.”^[158] The Brave New World was the logical outcome of the Keynesian belief that consumption is the antidote to recession.

Chemical opiates on the one hand; cultural stimulants on the other. If the human goal is to pursue pleasure and avoid pain, and if a regime has a total monopoly on the sources of pleasure, then that regime has created a realm of subjection like nothing ever before seen. Working together, the assemblage of opiates and stimulants available in the Brave New World, both cultural and chemical, constitute an order so finely calibrated to the workings of the human nervous system that there can be no escape. The same is true for the assemblage of stressors in Orwell’s Oceania. Hence, history itself has come to an end. In describing the end of history’s dialectic, both Orwell and Huxley hint at a historical model, a great transformation, in which the native stimulants and stressors of the past yield to a systematically designed array in the new world. Power, they suggest, is always mediated through the nervous system. The end of history comes about when a regime armed with the necessary technological apparatus hits upon the ideal combination of neurological controls.

It is a dazzling and disturbing idea.

We can set aside the intuition shared by Huxley and Orwell that transformations of this type are guided by the hand of totalitarian regimes, for although their model actually does describe with some accuracy the modus operandi of twentieth-century totalitarian regimes, it is probably less capable of describing past societies. Some of the most interesting trends in history, moreover, are those that emerge as the unforeseen and unintended consequences of shifts in practice or thought. When their model is purged of this totalitarian and voluntarist vision, however, it offers a startling new way to think about the transformations of the past. In the case study offered below, I would like to offer a glimpse at what such a history could look like. I shall begin with a brief review of relevant findings of neuroscience and related fields like cognitive archaeology before turning to a preliminary case study using evidence drawn from medieval and early modern Europe.

Why Europe? My own limited expertise, rather than any belief in Western European exceptionalism, is the chief reason. But Western European history does have several features that make it an interesting subject for a neurohistorical approach. As various observers have noted, medieval Latin Christendom was a region generally poor in psychopharmacological substances. There were plenty of cultural practices, however, that impinged on the nervous system. These were the components of a distinctive assemblage of traits that emerged in stages along with the rise of Latin Christendom. Then, across the long eighteenth century (from about 1688 to 1815), a distinctly different assemblage of traits came together.

First, the exchange of psychopharmacological substances like caffeine and opium accelerated all over the world. David Courtwright has called this “the psychoactive revolution.”^[159] Patterns of use changed. To take but one example, coffee—hitherto a medicine—became a luxury, an adjunct to entertainment, and eventually a staple. Expanding production led to a growing density of psychoactive substances in all global societies.

Second, there were transformations in the basic profile of available cultural practices that impinged on the nervous system, as evidenced by the luxury debates, the mania for collecting, the passions aroused by theater, and especially the anxieties surrounding what was known as “reading mania” or “reading fever.” It was a century, remarkably, in which contemporary observers were aware of the changing forms of addiction. A neurohistory is, necessarily, a deep and global history, but the full spectrum will emerge only after we have begun to piece together the local histories.^[160]

In the past few decades, enormous strides have been made in the fields of biological anthropology and paleohistorical archaeology. Genomic studies have enriched our understanding of behavioral traits and patterns of migration in the Paleolithic era (the old Stone Age). New dating techniques have supplied the chronological scaffolding that was missing or thin in many areas of deep human history.^[161] The emergence of the field of cognitive archaeology, a distant cousin of the better-known field of evolutionary psychology, has offered important new insights on both brain and behavior.^[162] All of this is leading to a robust new understanding of early human history.

One of the most significant questions of the emerging field of paleohistory is also the one that has been around the longest: what instigated the growth of the human brain? The size and shape of the brain case is easily graphed, and what that graph illustrates is a pattern of punctuated growth from the australopithecine brain (ca. 3.2 million years ago) to the modern brain. The brain is expensive tissue, and the large skulls needed to protect it are dangerous for both mothers and neonates. So what was the evolutionary benefit that offset the considerable costs of the large brain? One of the most vigorous arguments lately is the social intelligence hypothesis,^[163] which builds off the idea that humans have lived in cooperative groups for nearly two million years and are dependent on altruism like no other species. The brain, accordingly, grew to keep track of credits and debits, social alliances, and social standing. This new social context placed a premium on the ability to accurately read and act on social signals. In his studies on autism, Simon Baron-Cohen calls this “mind-reading.”^[164] Social intelligence created what evolutionary theorists have called a “cognitive arms race” in which the most important selection pressure was not the changing environment or the use of tools, but the need to keep up with everyone else’s mind-reading ability.

The changing use of the brain pushed the evolution of practices or mechanisms that interact with the dopamine reward and the stress response systems. These are ancient systems found in all reasonably complex animal species, for animals need to receive pleasure for doing good things and pain for doing bad things. The dopamine reward system works by generating dopamine in synapses; this excites the neurons and produces a feeling of pleasure or satisfaction. The stress response system generates discomfort through the reduction of dopamine and serotonin in synapses and through the release of stress hormones. In social species, the two systems are harnessed to the demands of cooperative life. Pro-social activity generates a reward. Stress mounts if the animal is at odds with or isolated from the group. The sensory-deprivation experiments first conducted on human subjects at McGill University in the 1950s vividly illustrate this point. Subjects who were isolated from sensory input—with frosted goggles, gloves, solitary rooms, white noise—would begin to hallucinate within a day or two. Every one of them was forced to abandon the experiment within a week. Horrifying studies conducted in the 1970s showed that newborn rhesus macaque monkeys went psychotic and suffered permanent neurological damage after being isolated for several months in the aptly named “Pit of Despair.”

Key to this psychological process is the need felt by most primates for daily contact. As the psychologist and primatologist Robin Dunbar has argued, grooming is not just about parasites; it is crucial for building and maintaining social relations.^[165] Grooming generates a pleasant dose of dopamine and serotonin, along with oxytocin, the peace-and-bonding neurotransmitter. Language, according to Dunbar, allows for gossip, a kind of verbal grooming. Using gossip, humans can extend the reach of chemical bonding across a much larger network. In practice, this means that humans can live in groups of unlimited size, unlike other primates. Dunbar’s insight is key to answering one of the great questions we ask today: how did large, imagined communities come to be?

In both birds and mammals, the sensitivity of this neurochemical system makes it susceptible to psychoactive substances. But the system is also open to things you do to yourself and especially open to things that other people do to you. Although Edward Bernays built an industry on the understanding that clever marketing could induce consumers to make purchases they didn’t really intend to make, he was not the first person to make this observation. Writing in the mid-sixteenth century, the French essayist Etienne de la Boétie observed, “theatres, games, plays, spectacles, marvellous beasts, medals, tableaux, and other such drugs [droguerie] were for the people of Antiquity the allurements of serfdom, the price for their freedom, the tools of tyranny.”^[166] To be enticed by what the Roman poet Juvenal had called “bread and circus” was to submit to voluntary servitude. La Boétie’s idea of voluntary servitude was an early contribution to a long intellectual thread leading through Marx and Gramsci to Huxley and beyond, to the cultural critique of late capitalism found in Neil Postman’s 1985 work, Amusing Ourselves to Death.^[167]

Primatologists have described a daily dialectic between the stress-response system and the dopamine reward system. Dominant males and females visit stress on subordinates the better to maintain their own high rank. Pleasurable grooming and same-sex sexuality among primates helps to build and repair social bonds and alliances. Among humans, the daily dialectic between the dopamine reward system and the stress response system is also a kind of historical dialectic. The neuroscientist Robert Sapolsky has offered the most vivid point of departure for this argument.^[168] Stress, he argues, is distributed unequally across the social spectrum. The poorer you are, the more stress you endure. The transitions that have taken place in recent human history—that is to say, the last ten thousand years—have created hierarchies of wealth and power that have institutionalized forms of stress. What we need to add to Sapolsky’s observation is the possibility that institutional stress can be balanced by practices that relieve stress and provide diversions. These can be cultural, as La Boétie divined, but they can also be psychopharmacological. To take a modern example, Frank Dikötter and his coauthors have argued that the consumption of opium in the Chinese countryside in the nineteenth century tended to increase in times of malnutrition. Foreign observers passing through the so-called opium villages would confuse cause and effect, blaming the starvation of the people on their consumption of opium.^[169] The institutionalized forms of stress that emerged in agrarian and post-agrarian societies prompted a growing human investment in opiates and pleasurable stimulants of all kinds, chemical and cultural. A whole economy came to be harnessed to this task.

This model proposes that human history has been shaped by a continuous dialectic between the dopamine reward system and the stress response system. The dialectic was initiated in Africa several million years ago with the emergence of hominins and cooperative living. It has been fed by the cognitive arms race and especially by changing human population densities. Significant steps were taken after modern humans colonized the globe, starting around 85,000 years ago. Agriculture, cities, and whole civilizations added new wrinkles. To return to the works discussed earlier, Huxley, following La Boétie, imagined that this dialectic could come to an end with the victory of pleasure. Orwell, like Sapolsky, favored stress.

The language of neuroscience is not strictly necessary when it comes to talking about changing patterns of reward and stress in human society. The point has been obvious enough to authors and essayists. But the neurobiology is helpful, for it confirms on a chemical level that there is no meaningful distinction between cultural practices and psychoactive chemicals. Both kinds of input are translated into the language of the nervous system. That language consists of synapses, neurochemicals, and a hideously complex grammar. At the level of the synapse, the effect of cultural traits and practices is similar to the effect of psychoactive substances. Culture, in this sense, is like a drug. But drugs themselves are part of culture, delivered by commerce and bound up in ritual forms. Patterns of use can and do change significantly from one historical society to another.

This insight allows us to fashion a category of analysis that embraces cultural stimulants along with their psychoactive counterparts. These are the “psychotropic mechanisms” mentioned earlier in this essay—the spectrum of devices, practices, or substances available in any culture that alter the nervous system to greater or lesser degrees and perform political or social work. Every political society has a characteristic assemblage of psychotropic mechanisms. The history outlined below is a history of transformation in psychotropic assemblages.

Medieval Latin Christendom, toward the end of the first millennium, was a world tucked away in the northwest corner of the Old World, at a remove from the vibrant civilizations and trade networks that stretched from Al-Andalus to Song Dynasty China. Gone were the psychotropic mechanisms of the ancient world: the theatres, games, and spectacles described by La Boétie, to which he could have added an eroticism worthy of the Brave New World. Europe at this time was a world in which the luxury items of the age, such as gold and ivory, and the spices, the fine silken fabrics of the great Islamic and Chinese civilizations, were all imported, mostly in exchange for slaves, and did not circulate much outside the great secular and ecclesiastical courts. It was a world largely bereft of psychoactive substances. Other Old World societies had their tea, coffee, hashish and marijuana, opium, and even the soma of the Vedas. New World societies had long since discovered coca, tobacco, peyote, and hallucinogens. None of these products was native to the European backwater.

The major exception was alcohol. Richard Unger has argued that northern Europeans consumed at least a quart of ale or “small beer” every day, matched in southern latitudes by wine.^[170] It is hard to avoid the impression of a continuously intoxicated society. Wolfgang Schivelbusch, indeed, has described a great transformation from what he called the “alcoholic stupor” of the middle ages to the common sense and industry of the caffeinated middle-class culture of early modern Europe.^[171] But this is an egregious misreading of the medieval evidence. Medieval wines, ales, and beers had lower alcohol content than their modern counterparts. Wine was a thin and vinegary substance, with an alcoholic content of no more than 5 percent and typically mixed with water at that. Ales and beers made from the first wort were not necessarily weaker than modern beer, but brewsters drew second and even third worts off the grain, resulting in what is called "small beer" with very little alcohol. Alcoholic beverages were consumed primarily for health and dietary reasons, not recreation. As Unger has put it bluntly, “the society did not know about alcoholism.”^[172]

Medieval Latin Christendom, in short, was a world in which the range of psychotropic mechanisms was largely restricted to the things people could do rather than the things people could ingest. How do we find evidence for these things? How do we describe the psychotropic assemblage of medieval Europe when we are necessarily limited to indirect evidence and inferential arguments? It is true that swings in body states among people in past societies cannot be studied through brain imaging technology. Even so, some alterations will express themselves on the outside of the body in the form of emotional displays or somatic gestures such as blushing, pallor, fainting, sighs, tears, and so on. We can, therefore, approach swings in body states indirectly, through observations drawn by contemporary observers. Happily, medieval Europe, although psychopharmacologically poor, is rich in surviving texts, and it is through written and illustrated evidence that we can begin to develop a partial understanding of medieval Europe’s psychotropic assemblage.

As it happens, scholars in literature and art history interested in the semiotics of nonverbal communication have long been aware of the somatic gestures in medieval sources. As Moshe Barasch has observed, the painter Giotto portrayed involuntary gestures with the same care and attention he gave to voluntary or purposive gestures.^[173] Yet medievalists have typically dismissed the study of somatic gestures, arguing that because they fail to carry what St. Augustine called a voluntas significandi (a desire to communicate), they cannot be the worthy subjects of historical inquiry.^[174] This is the “cognitive fallacy,” the mistaken belief that the only form of communication worth considering is voluntary communication. The autonomic nervous system is constantly engaged in communicating with other autonomic nervous systems. The substance of this communication is critically important for sub-cortical negotiations involving politics, social rank, forms of obligation, prosocial behavior, antisocial behavior—everything that is central to the work of history.

Medieval observers, who had a keen eye for somatic gestures, were in this respect more thoroughly aware than modern historians and literary scholars of the need to track all forms of nonverbal communication. In Le Grand Coutumier de France, for example, the late medieval French jurist Jacques d'Ableiges counseled judges to pay close attention to sworn witnesses who grow pale, blush, shift, tremble, or speak obscurely or unclearly.^[175] Gratian’s Decretum (a collection of canon law compiled in the twelfth century), as William Courtenay and Karl Shoemaker have recently discussed, has dozens of references to tears, key components of what we can call the canon law of weeping.^[176] For a more extended example, consider the marvelous description found in Raymond of Capua’s Life of St. Catherine of Siena, written around 1380.^[177] In addition to everything else she did, Catherine was a peacemaker. One day, Raymond sought her help in pacifying the troublesome Nanni di Ser Vanni. Catherine’s entreaties seemed to be going nowhere. With great ill-grace, however, Nanni finally agreed to let her try to resolve one of them. This is how Raymond describes the climactic scene:

In addition to offering somatic gestures like tears and constriction of the chest, medieval observers sometimes describe interesting body states without using somatic terminology. When Catherine first arrived, for example, Raymond described himself as being filled with joy.

Sifting through a range of medieval texts like this one, we find many bodies that are moved by joy or happiness. We find descriptions of compulsive behaviors. We find things that soothe as well as things that excite and agitate. Descriptions like these are scattered thinly but meaningfully across a variety of genres. Though rare in legal contracts and court records, they are not uncommon in narratives, such as chronicles, epics, and romances, as well as moral treatises and letters. So what happens when we take a census of these observations and explore the contexts in which they are found? It is true that literary descriptions are often stylized and conventional. But even if we cannot know whether St. Dominic wept copiously during his prayers, or whether El Cid’s eyes filled with tears as he groveled before his sovereign Alfonso, his mouth full of grass, we can perhaps draw legitimate inferences from the fact that tears are conventionally found in circumstances involving religious devotion and public self-humiliation.

Let me offer some highlights of a very preliminary census. Attributions of joy and ecstasy, along with tears and great exhalations, show up in many contexts. Not surprisingly, the evidence is skewed to religious experiences like sermons. Medieval observers of sermons were sensitive to the psychology of crowds. In their accounts, we