In his previous sally, he cited the story of Maria’s Shoe, a tall tale that has been circulating in the New Age community for decades, always growing in the telling. This story is the claim that a woman with a heart condition was hospitalized, and while unconscious with a heart attack, her spirit floated out of the coronary care unit to observe a shoe on a third-floor ledge. As has been shown, she described nothing that could not be learned by mundane observation, no supernatural events required, and further, that the story is peculiarly unverifiable: “Maria” cannot be found, not even in the hospital records, and no one has been found who even knew this woman. The entire story is hearsay with no independent evidence whatsoever.

Beauregard attempts to salvage the story by layering on more detail. The description of the shoe was very specific, he says, right down to the placement of the laces and the pattern of wear, and she could not possibly have learned this by overhearing staff talking about it because “it would have been difficult for Maria to understand the location of the shoe in the hospital and the details of its appearance because she spoke very little English.” This is a curious observation; the claim is that she could not understand a description of the shoe, but she was able to describe the shoe herself to a woman, Kimberly Clark Sharp, who did not understand Spanish.

“When I got to the critical-care unit, Maria was lying slightly elevated in bed, eyes wild, arms flailing, and speaking Spanish excitedly,” recounts Sharp. “I had no idea what she was saying, but I went to her and grabbed her by the shoulders. Our faces were inches apart, our eyes locked together, and I could see she had something important to tell me.”

The question isn’t whether a seriously ill woman with poor command of English could see the shoe; it’s whether a healthy, ambulatory, English-speaking woman who has made a career out of the myth of NDEs could see the shoe. Beauregard’s additions to the anecdote do not increase its credibility at all.

Beauregard adds another anecdote to the litany, the story of another cardiac patient who was resuscitated and later recounted seeing a particular nurse while his brain was not functional. Seriously — more anecdotes don’t help his case. He threatens to have even more of these stories in a book he’s in the process of publishing, but there’s no point. He could recite a thousand vague rumors and poorly documented examples with ambiguous interpretations, and it wouldn’t salvage his thesis.

This new anecdote is more of the same. The patient is comatose and with no heart rhythm when brought into the hospital; over a week later, he claims to recognize a particular nurse as having been present during his crisis, and mentions that she put his dentures in a drawer.

I am underwhelmed. I must introduce Beauregard to two very common terms that are well understood in the neuroscience community.

The first is confabulation. This is an extremely common psychological process in which we fill in gaps in our memory with fabrications. I described this in my previous response, but Beauregard chose to disregard it. The patient above has a large gap in his memory, but he knows that he existed in that period, and something must have happened; he knows that he was resuscitated in a hospital, so can imagine a scene in which he was surrounded by doctors and nurses; he knows that his dentures are missing, so he suspects that someone put them somewhere, likely one of the people surrounding him during the emergency. So his brain fills in the gap with a plausible narrative. This whole process is routine and unsurprising, and far more likely than that his mind went wandering away from his brain.

The second term is confirmation bias. Only positive responses that confirm Beauregard’s expectations are noted. The patient guessed that a nurse he met during his routine care was also present during his episode of unconsciousness, and he was correct. What if he’d guessed wrongly? That event would be unexceptional, nobody would have made note of it, and Beauregard would not now be trotting out this incident as a vindication of his hypothesis. This is one of the problems of building a case on anecdotes; without knowledge of the range and likelihood of various results, one can’t distinguish the selective presentation of chance events from a measurable phenomenon.

While unaware of basic concepts in science, Beauregard seems to readily adopt the most woo-ish buzzwords. His explanation for this purported power of the mind to exist independently of any physical substrate is, unfortunately and predictably, quantum mechanics. Every charlatan in the world seems to believe that attaching “quantum” to a word makes it magical and powerful and unquestionable. I have to accept Terry Pratchett’s rebuttal: “‘Let’s call it Quantum!’ is not an explanation.” And neither is Beauregard’s feeble insistence that the universe possesses quantum consciousness, that psychic powers represent quantum phenomena, or that there is an infinitely loving Cosmic Intelligence.

Beauregard then accuses me of having an ideological bias, and that I’m a fanatical fundamentalist. He, of course, is the dispassionate, objective observer with no ax to grind, only interested in reporting the scientific facts. Unfortunately, his book “The Spiritual Brain” reveals to the contrary that he has some very, very strange beliefs.

Individual minds and selves arise from and are linked together by a divine Ground of Being (or primordial matrix). That is the spaceless, timeless, and infinite Spirit, which is the ever-present source of cosmic order, the matrix of the whole universe, including both physics (material nature) and psyche (spiritual nature). Mind and consciousness represent a fundamental and irreducible property of the Ground of Being. Not only does the subjective experience of the phenomenal world exist within mind and consciousness, but mind, consciousness, and self profoundly affect the physical world…it is this fundamental unity and interconnectedness that allows the human mind to causally affect physical reality and permits psi interaction between humans and with physical or biological systems. With regard to this issue, it is interesting to note that quantum physicists increasingly recognize the mental nature of the universe.

If I am an ideologue, it’s only in that I demand that if you call something science, it bear some resemblance in method and approach to science, not mysticism. Beauregard insists on trying to endorse the babbling piffle above as science by reciting the number of publications he has made, and how much grant money he’s got, when I’m looking for verifiable, reproducible, measurable evidence.

I would also remind him that Isaac Newton, who was probably an even greater scientist than the inestimable Beauregard, wasted much of his later years on mysticism, too: from alchemy and the quest for the Philosopher’s Stone, to arcane biblical hermeneutics, extracting prophecies of the end of the world from numerological analyses of Revelation. While his mechanics and optics have stood the test of time, that nonsense has not. That his mathematics and physics are useful and powerful does not imply that he was correct in his calculation that the world will end before 2060 AD; similarly, Beauregard’s success in publishing in psychiatry journals does not imply that his unsupportable fantasies of minds flitting about unfettered by brains is reasonable.

That might be why some “Girls” writers take exception to their show being singled out for criticism. Here’s what writer Leslie Arfin tweeted in response to criticisms: “What really bothered me most about Precious was that there was no representation of ME.” (“Precious,” the 2009 film about a mentally and sexually abused teenager, featured a predominantly black cast.)

Why shouldn’t Arfin and creator Lena Durham be able to re-create their own private girl-world on screen? What responsibility do show runners have to represent diversity? Does it even matter? How do our brains respond when people of color are invisible or stereotyped on TV?

This is where science can help. I co-edited a book called “Are We Born Racist?,” which features new insights from psychology and neuroscience about what happens in our nervous systems when we encounter people of different races. And we found that decades of studies say yes, the racial vision of “Girls” does matter. For example, a series of four 2009 studies found that people who watched shows that featured negative nonverbal behavior toward blacks became more prejudiced themselves, as measured by tests of implicit bias — this was especially true when viewers didn’t recognize the behavior as negative. It seems that TV can indeed subconsciously induce racism.

So how can show runners correct for that? The research is overwhelmingly clear: job one is to confront the fact that racial difference exists. The new science of racism reveals that our brains do indeed seem to react negatively to people of different races — exposure of just milliseconds to a black face can cause white folks’ amygdalae to light up with fear.

Colorblindness doesn’t work because we never stop spotting differences in our environment.  Our brains are designed to do that; that’s how we survived on the savannah 50,000 years ago, and it’s how we survive in the globalized urban jungles of the 21st century. It takes an effort of will to cover your eyes and stick your fingers in your ears and shout, “Nah nah nah I’m not listening,” when confronted with racial difference. And doing that is what psychologists call “non-survival behavior,” something that belongs in the same category as smoking cigarettes and riding a motorcycle without a helmet.

The antidote to subconscious bias is not political correctness — shoehorning in a quirky, spunky black BFF for the girls will just annoy black viewers, instead of making the world a better place. Rather, the best cure for what ails shows like “Girls” is a dose of thoughtfulness, self-awareness and courageous originality.

The good news is that our brains get used to difference; in most situations, exposure to people of different races reduces prejudice. That’s a good reason for TV and movies to at least make an effort to show our cities in all their diversity. But that’s not all. As researchers have developed new and creative ways to induce racial nightmares in brain scanners, they’ve found that the prefrontal cortex — that’s the newest, most human part of the brain, the one responsible for long-term planning and intentional thought — is able to tell the oldest, least human part of the brain, the amygdala, to calm down. In other words, people can outthink and unlearn subconscious prejudice.

Some folks seem to think, as my colleague, UC Berkeley psychologist Rodolfo Mendoza-Denton writes, that “unconscious biases reveal ‘the real you’ — how you really feel about X or Y group despite your best, superficial efforts to hide it.” Some interpret this idea to mean that saying whatever ugly thing enters our heads is simply being honest. We don’t want to suppress our true savage nature, do we? We don’t want to sweep it under the rug, do we?

No, we don’t. And we should also be honest about how racially homogenous our social networks tend to be — if the quirky, spunky frenemies in “Girls” are all white, that’s just realistic, I agree. But shows like “Girls” improve when they implicitly and explicitly recognize that there are people in the world who aren’t like the protagonists, and that sometimes we all say stupid things.  So instead of being defensive, as Arfin was in her tweet, what if we just took knee-jerk bias for granted — and then also took it for granted that people can grow and correct for prejudice? What if we just, you know… had faith in each other?

“The assumption that prejudice and egalitarianism is an all-or-none proposition (i.e., one is either prejudiced, or one is egalitarian) makes the possibility that one may think or do something stereotypical very threatening, precisely because it would reveal one’s true nature,” Mendoza-Denton argues. But when we consciously condemn racism, that act of the prefrontal cortex is just as authentic and meaningful as the unconscious impulses we find in the amygdala. In fact, I’d argue that intentionally rejecting racism reveals the very essence of our humanity.

The trick is, quite simply, to acknowledge race and racism, and to talk about it. Many white parents avoid the subject like the plague — in one notorious instance, parents pulled out children en masse from a study when they learned it would entail talking about race. But this strategy doesn’t produce colorblind citizens. It creates shows like “Girls,” “Seinfeld” and “Sex in the City.” It perpetuates a society that historically has pretended to be entirely Anglo-Saxon.

In fact, many, many studies find that children whose parents talk with them about race ultimately become less prejudiced. Talking is how we become conscious of subconscious biases — bias against anyone or anything, not just people of different races. All this science stuff sounds high-minded and earnest, doesn’t it? Is it even possible to apply these insights to a TV show without wrecking its entertainment value? Is it possible to depict racially insular and casually prejudiced white people in a way that doesn’t promote insularity and prejudice, as “Girls” does?

“Mad Men” does it (for gender as well as race). The non-quirky, non-spunky main characters are all white, but race haunts the show, in ways that are mostly lost on the chain-smoking ad executives it depicts. The difference between “Mad Men” and “Girls” is simply that “Mad Men” sees its characters with a combination of compassionate objectivity and ruthless historical perspective. That’s the result of artistic integrity, not political correctness.

Take this video, for example. It’s easy to chuckle at the character, Pete Campbell. But as you watch this clip, think about the nuances involved in this interaction — the ways Pete and Hollis struggle to communicate across profound differences in social power.

And by the way, HBO has done it before. “The Sopranos” was a show about Italian-American mobsters who must, as with any modern line of employment, work with people different from themselves. In this scene, we see the crew discussing some workplace diversity issues, wiseguy-style.

It’s raw, racist and honest. But it’s more than that. The writing is also smart, self-aware and grounded in the real world. This kind of writing does not see moral seriousness and entertainment as a trade-off, an either-or. It’s a both-and.

“Girls” is actually a pretty good show; it made me laugh, it made me sigh. But the bloggers are right to ask for it to be smarter and better. It’s something we should always be asking of ourselves.

One such case was reported by Dutch cardiologist Pim van Lommel and his colleagues in an article published in The Lancet journal. Here is a brief summary of the case.

During a night shift an ambulance brings in a 44-year-old cyanotic, comatose man into the coronary care unit (CCU). This man had been found lying in a cold, damp meadow about an hour before. He was hypothermic and he had no heart rhythm. At arrival (at the CCU), he is placed upon a resuscitation bed. Next, he receives artificial respiration without intubation, while heart massage and defibrillation are also applied. When the medical team wants to intubate the patient, he turns out to have upper dentures in his mouth. A nurse removes these upper dentures and put them onto the “crash cart.” Meanwhile, extensive cardiopulmonary resuscitation (CPR) is continued.

After about an hour and a half the patient has sufficient heart rhythm and blood pressure, but he is still ventilated, intubated, and comatose. He is then transferred to the intensive care unit to pursue the necessary artificial respiration. After more than a week, the nurse meets with the patient, who is by now back on the cardiac ward. The moment he sees the nurse he says: “Oh, that nurse knows where my dentures are…you were there when I was brought into hospital and you took my dentures out of my mouth and put them onto that cart, it had all these bottles on it and there was this sliding drawer underneath and there you put my teeth.” The nurse was amazed because the patient remembered this happening while he was in the process of CPR (i.e. while his brain was not functional). Asked further, the patient reported that he had seen himself lying in bed, that he had perceived from above how nurses and doctors had been busy with CPR. He was also able to describe correctly and in detail the small room in which he had been resuscitated as well as the appearance of those present.

Dr. Myers also claims that Maria’s story has been completely demolished. Nothing could be further from the truth. Actually, skeptical investigators have attempted to debunk the case of Maria. However, they did not succeed in explaining how she was able to “see” that the little toe area of the shoe was worn and one of the laces was stuck underneath the heel while (of note, she was confined to bed and attached to physiological monitors). The debunkers suggested that Maria could have become aware of the shoe prior to her NDE. Since a shoe placed on the ledge of the north side of the third floor could have been visible, both inside and outside the hospital, to people who could have come into contact with Maria, she could have overhead from staff commenting on it. Still, even if this was true, it is highly unlikely that hospital workers would have talked in detail about the shoe’s appearance. In addition, it would have been difficult for Maria to understand the location of the shoe in the hospital and the details of its appearance because she spoke very little English.

Over the last several centuries in the West, many scientists have functioned within a strict materialist, reductionist framework that holds to one essential assumption: “Matter is all that exists.” This materialist viewpoint has become the lens through which most of us interpret the world, interact with it, and judge what is true. Within the view of materialism, everything is composed of collections of material particles. All that we experience—including our thoughts, feelings, beliefs, intentions, sense of self, and spiritual insights—results from electrochemical impulses in our brains.

Along with an increasing number of scientists, I argue that science should not be equated with materialist metaphysics. In my view, science should be an objective process of discovery, i.e. metaphysically neutral.

Corroborated veridical NDE perceptions during cardiac arrest (and several other phenomena discussed in “Brain Wars”) strongly suggest that so-called “scientific materialism” is not only limited, but wrong. In line with this, nearly a century ago, quantum mechanics (QM) dematerialized the classical universe by showing that it is not made of minuscule billiard balls, as drawings of atoms and molecules would lead us to believe. In other words, QM acknowledges that the physical world cannot be fully understood without making reference to mind and consciousness, that is, the physical world is no longer viewed as the primary or sole component of reality (this was well explained by Wolfgang Pauli, one of the founders of QM—I suppose Dr. Myers also considers Pauli to be another “mystical moron”).

It is not difficult to understand why Dr. Myers has launched a personal attack against me. He is well known as an ideologue (masquerading as a person of science) driven by an intense desire to further the materialist agenda. His tactics are nothing new: incendiary rhetoric, swearing, and insults to raise doubts about the competence and integrity of scientists (and others) who threaten his belief structure. I do not think that too many people are fooled by such blatantly deceptive tactics.

Full of hate and anger, Dr. Myers postures as a champion of rationality. But, as a matter of fact, he behaves like a fanatical fundamentalist engaged in a holy war to defend the materialist doctrine. His emotional attachment to this ideology leads him to deny the existence of phenomena that do not fit with his preconceived view of the world. In doing so, he avoids being forced to relinquish his deeply held, cherished beliefs.

In other respects, it is the first time I hear someone says that he found “The Spiritual Brain” (my previous book) unreadable and idiotically conceived. In fact, this book has received several favorable reviews and perhaps Dr. Myers does not have the intellectual sophistication required to appreciate its value.

Finally, with respect to my credibility as a neuroscientist, I would like to tell readers that I have authored/co-authored more than 100 publications (some in highly ranked journals) in neuroscience, psychology, and psychiatry. Alone and in collaboration with colleagues, I have amassed millions of dollars in grant money. Moreover, I have received a number of scientific awards. It is also noteworthy that I am not involved in the Intelligent Design debate and I am not affiliated with any religious organization.

The first clue that this is going to be bad is the author, Mario Beauregard. Beauregard was coauthor with Denyse O’Leary of one of the worst, that is, most incompetently written and idiotically conceived, books I’ve ever read, “The Spiritual Brain.” It’s not just that he thought it sensible to team up with a well-known intelligent-design crank, but that the content is unreadable and the “science” is gobbledy-gook — Beauregard is a well-established kook, and here he is, writing for Salon.

NDEs are evidence of nothing but the creative power of the human mind. NDE proponents are constantly trotting out the same tired old anecdotes and the same tired old bogus misinterpretations, and this article is just more of the same. If you’ve ever looked into the NDE literature, you’ll know that two cases that are repeatedly brought up are the 20- to 30-year-old stories of Pam and Maria’s shoe; they have become something close to legend. These stories are poorly documented — “Maria,” for instance, can’t even be found in any hospital records, despite a story that details many medical details. Beauregard blithely recounts this anecdotal story as evidence that NDEs are real.

Maria was a migrant worker who had a severe heart attack while visiting friends in Seattle. She was rushed to Harborview Hospital and placed in the coronary care unit. A few days later, she had a cardiac arrest but was rapidly resuscitated. The following day, Clark visited her. Maria told Clark that during her cardiac arrest she was able to look down from the ceiling and watch the medical team at work on her body. At one point in this experience, said Maria, she found herself outside the hospital and spotted a tennis shoe on the ledge of the north side of the third floor of the building. She was able to provide several details regarding its appearance, including the observations that one of its laces was stuck underneath the heel and that the little toe area was worn. Maria wanted to know for sure whether she had “really” seen that shoe, and she begged Clark to try to locate it.

Quite skeptical, Clark went to the location described by Maria — and found the tennis shoe. From the window of her hospital room, the details that Maria had recounted could not be discerned. But upon retrieval of the shoe, Clark confirmed Maria’s observations. “The only way she could have had such a perspective,” said Clark, “was if she had been floating right outside and at very close range to the tennis shoe. I retrieved the shoe and brought it back to Maria; it was very concrete evidence for me.”

The case is touted as a clear example of veridical perception. “Veridical” is one of the favorite words of the NDE/OBE crowd; it simply means an observation that aligns with reality, so they’re always babbling about people wafting about in a ghostly disembodied state and seeing things that no earth-bound human could possibly have seen, which are later confirmed. Unfortunately, all we get are second- and third-hand accounts full of embellishments, and tall tales whose highlights are depressingly mundane, such as seeing a shoe on a ledge. It’s always trivia that gets reported. It seems that all dead people want to do is hover.

And, of course, Maria’s story has been totally demolished. The little details are all inflated; for instance, the claim that details of a shoe on a ledge could not possibly be discerned has been tested on that hospital building, and it turns out that a shoe on the ledge actually is really easy to see and jumps out to the eye of people passing beneath.

So, a few well-worn exaggerations are all these guys have to go on. I don’t think Beauregard can claim science has had any “shocking results” when this is the best he’s got.

Furthermore, Beauregard, who is supposed to be a neuroscientist, says some awesomely stupid things.

This case is particularly impressive given that during cardiac arrest, the flow of blood to the brain is interrupted. When this happens, the brain’s electrical activity (as measured with EEG) disappears after 10 to 20 seconds. In this state, a patient is deeply comatose. Because the brain structures mediating higher mental functions are severely impaired, such patients are expected to have no clear and lucid mental experiences that will be remembered. Nonetheless, studies conducted in the Netherlands, United Kingdom, and United States have revealed that approximately 15 percent of cardiac arrest survivors do report some recollection from the time when they were clinically dead. These studies indicate that consciousness, perceptions, thoughts, and feelings can be experienced during a period when the brain shows no measurable activity.

This is another common claim. The subject, they say, was flat-lined during the incident — the heart was still and there was no brain activity, and yet, they claim, the subject was experiencing detailed perceptual events during this period of material inactivity. What they gloss over is the simple fact that, while there was definitely a period when their brain was functionally inert, they are describing these events afterward, in a period when their brain is fully active. Beauregard is making the ignorant mistake of assuming that our consciousness is a continuous stream of recorded mental activity, and that a remembered event must necessarily have actually occurred.

That’s not how memories work. Our brains don’t tuck away a movie of our experiences somewhere in our temporal lobe; they store a few little details away, with a web of associations, and basically reconstruct the event when we try to recall it. This is why eyewitness testimony is unreliable — memory is dynamic and constantly being modified by later experience. When we lose conscious awareness and later recover it, the brain has absolutely no problem inventing a continuous narrative to fill in the blanks, and in fact, the way our minds work, we want that narrative. To consider that we didn’t exist for an interval of time is something we linear creatures tend to shy away from.

So when someone claims that a report of a recollection from a time when they were clinically dead is evidence of a mind functioning during that period when the brain was nonfunctional, you should know  they’re full of shit. It’s evidence of no such thing.

I also have to add that all of the accounts of NDEs and other such out-of-body experiences (OBEs) are peculiar in their attachment to ordinary patterns of perception. They claim to become a noncorporeal, immaterial, invisible entity that floats around, but somehow, they use the same mundane senses they do in the body. How do invisible eyes capture photons? How do immaterial minds detect physical vibrations in the air? Sensory transduction is a real problem for beings that lack hair cells and photoreceptors, I would think. It’s much more likely that they are using those fleshy sensory organs (or even more likely, the memory of using those organs), while experiencing an illusion of detachment from their body.

No reservations trouble Beauregard, though. He blindly charges on to claim revelation.

These findings strongly challenge the mainstream neuroscientific view that mind and consciousness result solely from brain activity. As we have seen, such a view fails to account for how NDErs can experience — while their hearts are stopped — vivid and complex thoughts and acquire veridical information about objects or events remote from their bodies.

NDE studies also suggest that after physical death, mind and consciousness may continue in a transcendent level of reality that normally is not accessible to our senses and awareness. Needless to say, this view is utterly incompatible with the belief of many materialists that the material world is the only reality.

As I’ve said, the recollection of vivid and complex thoughts while the heart is stopped is not only easily explained, it’s pretty much the default understanding by neuroscientists of how the brain works. The acquisition of veridical information would be more difficult to explain… if it had ever occurred. Trundling out the same hoary folk tales and anecdotes is not at all convincing that it has.

He is right that this idea of minds existing independently of brains is incompatible with materialist views. It’s also incompatible with the existing evidence, and he has presented no counter-evidence. His extremely badly argued article is yet another piece of evidence, though, that Beauregard is a crank.

P.S. It’s a shame that tripe got published in Salon, but don’t read the comments, or you’ll discover why it got published. There sure are a lot of mystically inclined, quantum-woo-spouting diddledingles fulminating away in their readership.

The logic of associating personalities with specific drugs seems natural. A German-British psychologist named Hans Eysenck spent the mid-20th century turning the eye of the scientific community from Freud’s behavior-based theories to individualized psychology—pioneering the science of personality. He considered this pursuit of matching personalities with drugs a pet project.

Eynsenck believed the ways people are inclined to think aren’t always the ways that make us feel best. And because drugs are the easiest way to modify temperament, it’s only natural for us to seek out those substances that keep us on an even keel. For instance, he thought that introverts, whose brains are always chewing at problems, should crave depressants to quiet the incessant mental chatter. Extroverts, easily bored, should chase the rush of stimulants.

His theory condensed individualized drug cravings into an easy, logical framework—but he was wrong. Or at least, he vastly oversimplified the concepts of both “personality” and “drugs.” Worse, his theory wasn’t borne out by research. Study after study showed both introverts and extroverts drinking alcohol (a depressant) to excess. And extroverts didn’t limit themselves to uppers; it seemed they would reach for all kinds of substances.

So where does that leave us? Well, scientists kept trying to tie the two nebulous concepts together. Over the years, as new methods of personality screening emerged, researchers continued to distribute questionnaires to groups of drug addicts. One major breakthrough came when four sets of psychologists independently realized in the 1980s and 1990s that a person’s personality traits—tendencies that are partially genetic and tend to last throughout life—can be pretty reliably described using five factors.

Introversion and extroversion weren’t enough, they thought. We should also consider openness to new experiences (think Bear Grylls), conscientiousness (Haruki Marukami), agreeableness (Mother Theresa) and neuroticism (Woody Allen) when trying to understand why people act the way they do. Thus armed, personality psychologists began fitting the various personality traits they had come up with over the years into what came to be called the “Big Five.” And lo, with a more accurate representation of traits, a connection between personality and drug use began to emerge.

People who tested high on neuroticism (indicating that they tend to be impulsive, emotionally unstable and anxious), low on conscientiousness (tending to be disorganized, unambitious and lazy), and low on agreeableness (tending to be uncooperative, unhelpful or misanthropic), were more likely to have problems with alcohol or drugs than people whose scores were closer to the middle, or reversed. Perhaps more interestingly to the question of whether personality traits led their owners to cocaine over alcohol, or marijuana over mushrooms, higher scores for each risky trait were linked to higher likelihood of using “hard” drugs like heroin, amphetamines or crack.

“There is some evidence that the more ‘bad’ traits you have, the harder the drugs you’re going to use,” says Michigan State Department of Psychology professor Chris Hopwood. “So super, super-impulsive, sensation-seeking, neurotic people might be inclined to use something like heroin, for example, whereas if you’re a little bit less impulsive or have more anxiety about things maybe you wouldn’t. Maybe you would use other drugs but you would be too afraid to use heroin.”

Not all the personality factors that appear in people with drug problems are negative, however:

Sensation-seeking—a facet of openness to experience that’s common among extreme sports athletes, explorers, philanderers and roller coaster-enthusiasts—is almost always associated with drug abuse, but doesn’t necessarily scale with using harder drugs. Marijuana users, for instance, have been shown to be high in sensation-seeking, with closer-to-average levels of neuroticism.

Sensation-seeking seems to be about 60 percent heritable—meaning about 60 percent of the trait comes from your genes—and appears to be related to the brain’s dopamine reward system, the same system that makes most drugs of abuse pleasurable. Sensation-seeking may even be related to where you live, through interactions with neighbors—or, in the case of, say, New York City, through self-selection. A study by Jason Rentfrow, Sam Gosling and Jeff Potter that was analyzed by Richard Florida on the Atlantic’s Atlantic Cities blog showed that Openness to Experience scaled with drug use when compared within states. And which states had the highest levels of both illicit drug use and openness? Colorado, Vermont, Oregon, Washington, Nevada, Massachusetts, New York and California.

Given the personality characteristics that seemed to split “hard” versus “soft” drugs, scientists began to wonder if—even if they couldn’t predict who would take uppers over downers—there was a way to predict who would become an alcoholic and who would abuse illegal drugs. The studies showed some remarkable similarities: One study conducted among veterans suggested that all addicts share interpersonal styles that tend toward loner, rebel and pessimist stereotypes, for example, which surprised no one who has ever seen “Leaving Las Vegas.” But there did appear to be a little something extra that could push a person into hard drug addiction.

People who use illicit drugs often have been shown to have higher rates of both extroversion and susceptibility to boredom, which may drive them into more situations where drugs appear, or simply make them more likely to crave new subjective experiences. And those who are particularly susceptible to boredom have been shown to use opiates more often.

But this is where the studies break down. Most research on the topic of how personality relates to drugs of choice is conducted among people who already have drugs of choice—addicts. And as any addict knows, once you’ve taken a shine to a drug, it can be exceedingly difficult to disentangle the personality factors that came before from the ones that came after. By the time the personality questionnaires are administered, who’s to say what caused the drug use and what the drug use caused?

“It could go either way,” says Hopson. “A person who uses heroin might end up having problems in their life. Perhaps he loses his job, perhaps then he starts stealing things. You could easily tell a story that goes, the heroin started first and then the person started doing all kinds of mean antisocial things. Or you could tell a story that says that the person was sort of a ‘bad’ person, if you’ll forgive the language, and one of the bad things they did was use heroin.”

There are also direct effects of drugs that scientists have to consider. Crack and cocaine abusers, for example, have shown personality traits related to the symptom of paranoia in certain studies, as well as depression and impulsivity and a trait terrifyingly called “psychoticism.” Because long-term crack or cocaine use can cause many of these effects, however, it’s unlikely that those traits cause people to take up stimulants. Rather, it appears that long-term crack or cocaine use might be able to alter the expression of certain traits to create a “stimulant user profile.”

Regardless of the qualms of scientists, however, quiz websites and message boards hoping to connect personality to a particular drug have popped up all over the Internet. Many focus on Myers-Briggs personality types (ENFP, ISTJ, etc.), which are commonly used by career counselors to assess how people prefer to perceive and organize information. Others skip the science altogether, selecting a drug you’re likely to use based on the clothes you wear, the events you attend, where you live, and your perceived flaws.

Will science ever reach that degree of accuracy—explaining just what it is that seems to make neurotic writers more likely to drink than use heroin? It’s certainly possible, says Hopson. “One way to think about personality is in terms of traits, which are stable and heritable. But you can also think about personality dynamics, like how do I react if you insult me, for example. That’s sort of my guess is that which drugs you use depend on the more complicated personality dynamics.”

Assuming you’ve got the traits that push you toward drug use in the first place, what else might lead you to one substance over another? Hopson says factors that play a role include what your parents use, what your friends use, and even simply what’s available where you live. Which perhaps explains Hemingway’s situation better than we could have expected: there sure was a lot of rum in Cuba.