Can’t count sheep? You could have aphantasia 
 
 If counting sheep is an abstract concept, or you are unable to visualise the faces of loved ones, you could have aphantasia – a newly defined condition to describe people who are born without a “mind’s eye”. 
 
 Some people report a significant impact on their lives from being unable to visualise memories of their partners, or departed relatives. Others say that descriptive writing is meaningless to them, and careers such as architecture or design are closed to them, as they would not be able to visualise an end product. 
 
 Cognitive neurologist Professor Adam Zeman, at the University of Exeter Medical School, has revisited the concept of people who cannot visualise, which was first identified by Sir Francis Galton in 1880 A 20th century survey suggested that this may be true of 2.5% of the population – yet until now, this phenomenon has remained largely unexplored. 
 
 Visualisation is the result of activity in a network of regions widely distributed across the brain, working together to enable us to generate images on the basis of our memory of how things look. These regions include areas in the frontal and parietal lobes, which ‘organise’ the process of visualisation, together with areas in the temporal and occipital lobes, which represent the items we wish to call to the mind’s eye, and give visualisation its ‘visual’ feel. An inability to visualise could result from an alteration of function at several points in this network. This problem has been described previously following major brain damage and in the context of mood disorder. Now, Professor Zeman and his team are conducting further studies to find out more about why some people are born with poor or diminished visual imagery ability. 
 
 The recent research came about by serendipity. The American science journalist, Carl Zimmer, wrote an article in Discover magazine about a previous paper by Professor Zeman reporting a man who lost his mind’s eye in his sixties following a cardiac procedure. Professor Zeman was then contacted by 21 individuals who recognised their own experience in the Discover article, but had never been able to imagine. Professor Zeman and colleagues describe these patients’ experience in a paper just published in the journal Cortex. 
 
 Dame Gill Morgan, from Devon in South West England, made contact with Professor Zeman as a result of this coverage. The Chair of NHS Providers first realised that her ability to conjure a mental picture differed from her peers during management training in her 20s. She said: “We were told to ‘visualise a sunrise’, and I thought ‘what on Earth does that look like’ – I couldn’t picture it at all. I could describe it – I could tell you that the sun comes up over the horizon and the sky changes colour as it gets lighter, but I can’t actually see that image in my mind.” 
 
 Dame Gill has a successful career and does not feel hindered by her lack of a “mind’s eye”. But she said: “I became more aware of it when my mum died, as I can’t remember her face. I now realise that others can conjure up a picture of someone they love, and that did make me feel sad, although of course I remember her in other ways. I can describe the way she stood on the stairs for a photo for example, I just can’t see it.” 
 
 Dame Gill believes her excellent memory may have developed in part to compensate for her lack of visual imagination. “If I have to recount something that’s absent, I have to reconstruct it from the facts I know about it, rather than view it in my mind.” 
 
 Niel Kenmuir, 39, from Lancaster in the UK, first realised he could not visualise images at primary school. “I can remember not understanding what 'counting sheep' entailed when I couldn't sleep. I assumed they meant it in a figurative sense. When I tried it myself, I found myself turning my head to watch invisible sheep fly by. I’ve spent years looking online for information about my condition, and finding nothing. I’m very happy that it is now being researched and defined.” 
 
 Niel works in a bookshop and is an avid reader, but avoids books with vivid landscape descriptions as they bring nothing to mind for him. “I just find myself going through the motion of reading the words without any image coming to mind,” he said. “I usually have to go back and read a passage about a visual description several times – it’s almost meaningless.” 
 
 Niel studied philosophy, which is rich in visual imagery, but this aspect was lost on him. The way he explains it, though, he does understand the mechanics behind it. He said: “The mind’s eye is a canvas, and the neurones work together to project onto it. The neurones are all working fine, but I don’t have the canvas”. 
 
 Asked if it had impacted on his life, he said: “I have never been ambitious, and wondered if an inability to 'imagine myself in a place ten years from now' as a concrete image has affected this. I also find it difficult to jump from abstract thought to concrete examples, although I think a positive consequence is that I am perhaps better at thinking abstractly than many other people.” 
 
 Professor Zeman said: “This intriguing variation in human experience has received little attention. Our participants mostly have some first-hand knowledge of imagery through their dreams: our study revealed an interesting dissociation between voluntary imagery, which is absent or much reduced in these individuals, and involuntary imagery, for example in dreams, which is usually preserved.” 
 
 Professor Zeman is pursuing the study of aphantasia through an interdisciplinary project funded by the Arts and Humanities Research Council (AHRC), The Eye’s Mind - a study of the neural basis of visual imagination and its role in culture. The AHRC project involves, among others, the artist Susan Aldworth, art historian John Onians and philosopher, Fiona Macpherson. 
 
 
 
 Read Professor Zeman's post on aphantasia on The Exeter Blog. ||||| One day in 2005, a retired building surveyor in Edinburgh visited his doctor with a strange complaint: His mind’s eye had suddenly gone blind. 
 
 The surveyor, referred to as MX by his doctors, was 65 at the time. He had always felt that he possessed an exceptional talent for picturing things in his mind. The skill had come in handy in his job, allowing MX to recall the fine details of the buildings he surveyed. Just before drifting off to sleep, he enjoyed running through recent events as if he were watching a movie. He could picture his family, his friends, and even characters in the books he read. 
 
 Then these images all vanished. The change happened shortly after MX went to a hospital to have his blocked coronary arteries treated. As a cardiologist snaked a tube into the arteries and cleared out the obstructions, MX felt a “reverberation” in his head and a tingling in his left arm. He didn’t think to mention it to his doctors at the time. But four days later he realized that when he closed his eyes, all was darkness. 
 
 Worried, MX paid a visit to Adam Zeman, a neurologist at the Peninsula Medical School in Exeter, England. Zeman was so intrigued by the case that he teamed up with Sergio Della Sala, a cognitive neuroscientist at the University of Edinburgh who specializes in how the brain handles visual information. Neither Zeman nor Della Sala could offer MX a cure for his condition, unfortunately, but they recognized a rare chance to study how the mind’s eye works. Della Sala proposed running a series of exams. MX gave his consent. 
 
 Scientists have long speculated that the act of seeing things in our mind’s eye employs some of the same brain circuits that we use when seeing with our physical eyes. A number of brain scan studies have supported this view. When you look at a person up close, for example, a particular network of brain regions becomes active, including areas that process raw signals from your eyes as well as more sophisticated regions that recognize individual faces. When you close your eyes and conjure up a face, the parts of the brain that receive signals from the eyes are dormant, but the regions that recognize the features defining an individual again light up. 
 
 MX gave Della Sala and Zeman the chance to test two ideas about the role of the mind’s eye in our inner life. Some scientists have argued that the mind’s eye is constantly at work whenever we look at our internal simulations of the world. Stephen Kosslyn, a Harvard psychologist, goes so far as to argue that we rely on the mind’s eye to make decisions about what we should do in the future. When we start driving home from a friend’s house, for example, we envision the different routes we can take in order to decide on the best way to go. 
 
 Kosslyn has his critics, though. Zenon Pylyshyn, a cognitive scientist at Rutgers University, doesn’t think mental images are essential to figuring such things out. We all have the experience of picturing things in our heads, of course. If someone asks you how many paws are on a cat, you may see the image of a cat in your mind and count the paws. But the experience of using your mind’s eye doesn’t fully explain the mental processing that goes on beneath the surface. There may be other, more essential computations that lead you to your conclusion. 
 
 To test these competing interpretations, Della Sala and Zeman put MX through a battery of tests. First they wanted to find out whether the problem with his mind’s eye was just one part of a greater disorder. They tested his other faculties, such as his ability to make decisions and form memories. To see just how unusual MX was, the scientists decided to assemble a group of control subjects who were similar to him except for his complaint, so they recruited 10 male architects around the age of 60. 
 
 The tests revealed that MX was, for the most part, pretty much like the other men. He had a high IQ and a reliable memory. He did an excellent job at playing a card-swapping game in which the rules could change unexpectedly. His vision was normal, and he could easily put names to the faces of famous people shown to him. In other words, the vision-processing networks in his brain and his memory systems were in good working order. 
 
 When the scientists tested the mind’s eye of MX, though, the difference was stark. The researchers gave all their subjects a standardized test called the Vividness of Visual Imagery Questionnaire. They asked each participant to picture things like a landscape and a friend. Then the scientists had each man rate the image that came to mind. If it was as vivid as normal vision, he was asked to score it a 5. If there was no mental image at all—if the subject knew only that he was thinking of an object—he was to give it a score of 1. Most of the men scored high on the test. MX scored as low as possible, racking up a bunch of 1s. 
 
 Della Sala and Zeman scanned MX’s brain to see if they could find the source of this deficit. They first showed him a series of faces. MX’s brain responded in much the same way as the architects’ brains did, activating a network of regions that process vision and recognize individuals. Then the scientists showed their test subjects a series of names of famous people. As they read each name, the men were asked to picture that person. In the brains of the control group, the mind’s-eye regions became active, much as before. But in MX’s brain, those regions remained quiet. Even though the individual regions of his brain were working normally, some of the connections seemed to be down. ||||| Media playback is unsupported on your device Media caption "When I think about my fiancee, there's no image" Niel Kenmuir on living with aphantasia 
 
 Close your eyes and imagine walking along a sandy beach and then gazing over the horizon as the Sun rises. How clear is the image that springs to mind? 
 
 Most people can readily conjure images inside their head - known as their mind's eye. 
 
 But this year scientists have described a condition, aphantasia, in which some people are unable to visualise mental images. 
 
 Niel Kenmuir, from Lancaster, has always had a blind mind's eye. 
 
 He knew he was different even in childhood. "My stepfather, when I couldn't sleep, told me to count sheep, and he explained what he meant, I tried to do it and I couldn't," he says. 
 
 "I couldn't see any sheep jumping over fences, there was nothing to count." 
 
 Our memories are often tied up in images, think back to a wedding or first day at school. 
 
 As a result, Niel admits, some aspects of his memory are "terrible", but he is very good at remembering facts. 
 
 And, like others with aphantasia, he struggles to recognise faces. 
 
 Yet he does not see aphantasia as a disability, but simply a different way of experiencing life. 
 
 Take the aphantasia test 
 
 It is impossible to see what someone else is picturing inside their head. 
 
 Psychologists use the Vividness of Visual Imagery Questionnaire, which asks you to rate different mental images, to test the strength of the mind's eye. 
 
 The University of Exeter has developed an abridged version that lets you see how your mind compares. 
 
 You must have JavaScript enabled for this quiz to show! 
 
 Mind's eye blind 
 
 Ironically, Niel now works in a bookshop, although he largely sticks to the non-fiction aisles. 
 
 His condition begs the question what is going on inside his picture-less mind. I asked him what happens when he tries to picture his fiancee. 
 
 "This is the hardest thing to describe, what happens in my head when I think about things," he says. 
 
 "When I think about my fiancee there is no image, but I am definitely thinking about her, I know today she has her hair up at the back, she's brunette. 
 
 "But I'm not describing an image I am looking at, I'm remembering features about her, that's the strangest thing and maybe that is a source of some regret." 
 
 The response from his mates is a very sympathetic: "You're weird." 
 
 But while Niel is very relaxed about his inability to picture things, it is a cause of distress for others. 
 
 One person who took part in a study into aphantasia said he had started to feel "isolated" and "alone" after discovering that other people could see images in their heads. 
 
 Being unable to reminisce about his mother years after her death led to him being "extremely distraught". 
 
 The super-visualiser 
 
 At the other end of the spectrum is children's book illustrator, Lauren Beard, whose work on the Fairytale Hairdresser series will be familiar to many six-year-olds. 
 
 Her career relies on the vivid images that leap into her mind's eye when she reads text from her author. 
 
 When I met her in her box-room studio in Manchester, she was working on a dramatic scene in the next book. 
 
 The text describes a baby perilously climbing onto a chandelier. 
 
 "Straightaway I can visualise this grand glass chandelier in some sort of French kind of ballroom, and the little baby just swinging off it and really heavy thick curtains," she says. 
 
 "I think I have a strong imagination, so I can create the world and then keep adding to it so it gets sort of bigger and bigger in my mind and the characters too they sort of evolve. 
 
 "I couldn't really imagine what it's like to not imagine, I think it must be a bit of a shame really." 
 
 Media playback is unsupported on your device Media caption How good is your visual imagination? 
 
 Not many people have mental imagery as vibrant as Lauren or as blank as Niel. They are the two extremes of visualisation. 
 
 Adam Zeman, a professor of cognitive and behavioural neurology, wants to compare the lives and experiences of people with aphantasia and its polar-opposite hyperphantasia. 
 
 His team, based at the University of Exeter, coined the term aphantasia this year in a study in the journal Cortex. 
 
 Prof Zeman tells the BBC: "People who have contacted us say they are really delighted that this has been recognised and has been given a name, because they have been trying to explain to people for years that there is this oddity that they find hard to convey to others." 
 
 How we imagine is clearly very subjective - one person's vivid scene could be another's grainy picture. 
 
 But Prof Zeman is certain that aphantasia is real. People often report being able to dream in pictures, and there have been reported cases of people losing the ability to think in images after a brain injury. 
 
 He is adamant that aphantasia is "not a disorder" and says it may affect up to one in 50 people. 
 
 But he adds: "I think it makes quite an important difference to their experience of life because many of us spend our lives with imagery hovering somewhere in the mind's eye which we inspect from time to time, it's a variability of human experience." 
 
 If you think you have aphantasia or hyperphantasia and would like to be involved in Prof Zeman's research he is happy to be contacted at a.zeman@exeter.ac.uk ||||| Once upon a time, a neurosurgeon named Eben Alexander contracted a bad case of bacterial meningitis and fell into a coma. While immobile in his hospital bed, he experienced visions of such intense beauty that they changed everything—not just for him, but for all of us, and for science as a whole. According to Newsweek, Alexander’s experience proves that consciousness is independent of the brain, that death is an illusion, and that an eternity of perfect splendor awaits us beyond the grave—complete with the usual angels, clouds, and departed relatives, but also butterflies and beautiful girls in peasant dress. Our current understanding of the mind “now lies broken at our feet”—for, as the doctor writes, “What happened to me destroyed it, and I intend to spend the rest of my life investigating the true nature of consciousness and making the fact that we are more, much more, than our physical brains as clear as I can, both to my fellow scientists and to people at large.” 
 
 Well, I intend to spend the rest of the morning sparing him the effort. Whether you read it online or hold the physical object in your hands, this issue of Newsweek is best viewed as an archaeological artifact that is certain to embarrass us in the eyes of future generations. Its existence surely says more about our time than the editors at the magazine meant to say—for the cover alone reveals the abasement and desperation of our journalism, the intellectual bankruptcy and resultant tenacity of faith-based religion, and our ubiquitous confusion about the nature of scientific authority. The article is the modern equivalent of a 14th-century woodcut depicting the work of alchemists, inquisitors, Crusaders, and fortune-tellers. I hope our descendants understand that at least some of us were blushing. 
 
 As many of you know, I am interested in “spiritual” experiences of the sort Alexander reports. Unlike many atheists, I don’t doubt the subjective phenomena themselves—that is, I don’t believe that everyone who claims to have seen an angel, or left his body in a trance, or become one with the universe, is lying or mentally ill. Indeed, I have had similar experiences myself in meditation, in lucid dreams (even while meditating in a lucid dream), and through the use of various psychedelics (in times gone by). I know that astonishing changes in the contents of consciousness are possible and can be psychologically transformative. 
 
 And, unlike many neuroscientists and philosophers, I remain agnostic on the question of how consciousness is related to the physical world. There are, of course, very good reasons to believe that it is an emergent property of brain activity, just as the rest of the human mind obviously is. But we know nothing about how such a miracle of emergence might occur. And if consciousness were, in fact, irreducible—or even separable from the brain in a way that would give comfort to Saint Augustine—my worldview would not be overturned. I know that we do not understand consciousness, and nothing that I think I know about the cosmos, or about the patent falsity of most religious beliefs, requires that I deny this. So, although I am an atheist who can be expected to be unforgiving of religious dogma, I am not reflexively hostile to claims of the sort Alexander has made. In principle, my mind is open. (It really is.) 
 
 But Alexander’s account is so bad—his reasoning so lazy and tendentious—that it would be beneath notice if not for the fact that it currently disgraces the cover of a major newsmagazine. Alexander is also releasing a book at the end of the month, Proof of Heaven: A Neurosurgeon’s Journey into the Afterlife, which seems destined to become an instant bestseller. As much as I would like to simply ignore the unfolding travesty, it would be derelict of me to do so. 
 
 But first things first: You really must read Alexander’s article. 
 
 I trust that doing so has given you cause to worry that the good doctor is just another casualty of American-style Christianity—for though he claims to have been a nonbeliever before his adventures in coma, he presents the following self-portrait: 
 
 Although I considered myself a faithful Christian, I was so more in name than in actual belief. I didn’t begrudge those who wanted to believe that Jesus was more than simply a good man who had suffered at the hands of the world. I sympathized deeply with those who wanted to believe that there was a God somewhere out there who loved us unconditionally. In fact, I envied such people the security that those beliefs no doubt provided. But as a scientist, I simply knew better than to believe them myself. 
 
 What it means to be a “faithful Christian” without “actual belief” is not spelled out, but few nonbelievers will be surprised when our hero’s scientific skepticism proves no match for his religious conditioning. Most of us have been around this block often enough to know that many “former atheists”—like Francis Collins—spent so long on the brink of faith, and yearned for its emotional consolations with such vampiric intensity, that the slightest breeze would send them spinning into the abyss. For Collins, you may recall, all it took to establish the divinity of Jesus and the coming resurrection of the dead was the sight of a frozen waterfall. Alexander seems to have required a ride on a psychedelic butterfly. In either case, it’s not the perception of beauty we should begrudge but the utter absence of intellectual seriousness with which the author interprets it. 
 
 Everything—absolutely everything—in Alexander’s account rests on repeated assertions that his visions of heaven occurred while his cerebral cortex was “shut down,” “inactivated,” “completely shut down,” “totally offline,” and “stunned to complete inactivity.” The evidence he provides for this claim is not only inadequate—it suggests that he doesn’t know anything about the relevant brain science. Perhaps he has saved a more persuasive account for his book—though now that I’ve listened to an hour-long interview with him online, I very much doubt it. In his Newsweek article, Alexander asserts that the cessation of cortical activity was “clear from the severity and duration of my meningitis, and from the global cortical involvement documented by CT scans and neurological examinations.” To his editors, this presumably sounded like neuroscience. 
 
 The problem, however, is that “CT scans and neurological examinations” can’t determine neuronal inactivity—in the cortex or anywhere else. And Alexander makes no reference to functional data that might have been acquired by fMRI, PET, or EEG—nor does he seem to realize that only this sort of evidence could support his case. Obviously, the man’s cortex is functioning now—he has, after all, written a book—so whatever structural damage appeared on CT could not have been “global.” (Otherwise, he would be claiming that his entire cortex was destroyed and then grew back.) Coma is not associated with the complete cessation of cortical activity, in any case. And to my knowledge, almost no one thinks that consciousness is purely a matter of cortical activity. Alexander’s unwarranted assumptions are proliferating rather quickly. Why doesn’t he know these things? He is, after all, a neurosurgeon who survived a coma and now claims to be upending the scientific worldview on the basis of the fact that his cortex was totally quiescent at the precise moment he was enjoying the best day of his life in the company of angels. Even if his entire cortex had truly shut down (again, an incredible claim), how can he know that his visions didn’t occur in the minutes and hours during which its functions returned? 
 
 I confess that I found Alexander’s account so alarmingly unscientific that I began to worry that something had gone wrong with my own brain. So I sought the opinion of Mark Cohen, a pioneer in the field of neuroimaging who holds appointments in the Departments of Psychiatry & Biobehavioral Science, Neurology, Psychology, Radiological Science, and Bioengineering at UCLA. (He was also my thesis advisor.) Here is part of what he had to say: 
 
 This poetic interpretation of his experience is not supported by evidence of any kind. As you correctly point out, coma does not equate to “inactivation of the cerebral cortex” or “higher-order brain functions totally offline” or “neurons of [my] cortex stunned into complete inactivity”. These describe brain death, a one hundred percent lethal condition. There are many excellent scholarly articles that discuss the definitions of coma. (For example: 1 & 2) 
 
 
 
 We are not privy to his EEG records, but high alpha activity is common in coma. Also common is “flat” EEG. The EEG can appear flat even in the presence of high activity, when that activity is not synchronous. For example, the EEG flattens in regions involved in direct task processing. This phenomenon is known as event-related desynchronization (hundreds of references). 
 
 
 
 As is obvious to you, this is truth by authority. Neurosurgeons, however, are rarely well-trained in brain function. Dr. Alexander cuts brains; he does not appear to study them. “There is no scientific explanation for the fact that while my body lay in coma, my mind—my conscious, inner self—was alive and well. While the neurons of my cortex were stunned to complete inactivity by the bacteria that had attacked them, my brain-free consciousness ...” True, science cannot explain brain-free consciousness. Of course, science cannot explain consciousness anyway. In this case, however, it would be parsimonious to reject the whole idea of consciousness in the absence of brain activity. Either his brain was active when he had these dreams, or they are a confabulation of whatever took place in his state of minimally conscious coma. 
 
 
 
 There are many reports of people remembering dream-like states while in medical coma. They lack consistency, of course, but there is nothing particularly unique in Dr. Alexander’s unfortunate episode. 
 
 Okay, so it appears that my own cortex hasn’t completely shut down. In fact, there are further problems with Alexander’s account. Not only does he appear ignorant of the relevant science, but he doesn’t realize how many people have experienced visions similar to his while their brains were operational. In his online interview we learn about the kinds of conversations he’s now having with skeptics: 
 
 I guess one could always argue, “Well, your brain was probably just barely able to ignite real consciousness and then it would flip back into a very diseased state,” which doesn’t make any sense to me. Especially because that hyper-real state is so indescribable and so crisp. It’s totally unlike any drug experience. A lot of people have come up to me and said, “Oh that sounds like a DMT experience,” or “That sounds like ketamine.” Not at all. That is not even in the right ballpark. 
 
 
 
 Those things do not explain the kind of clarity, the rich interactivity, the layer upon layer of understanding and of lessons taught by deceased loved ones and spiritual beings. 
 
 “Not even in the right ballpark”? His experience sounds so much like a DMT trip that we are not only in the right ballpark, we are talking about the stitching on the same ball. Here is Alexander’s description of the afterlife: 
 
 I was a speck on a beautiful butterfly wing; millions of other butterflies around us. We were flying through blooming flowers, blossoms on trees, and they were all coming out as we flew through them… [there were] waterfalls, pools of water, indescribable colors, and above there were these arcs of silver and gold light and beautiful hymns coming down from them. Indescribably gorgeous hymns. I later came to call them “angels,” those arcs of light in the sky. I think that word is probably fairly accurate…. 
 
 
 
 Then we went out of this universe. I remember just seeing everything receding and initially I felt as if my awareness was in an infinite black void. It was very comforting but I could feel the extent of the infinity and that it was, as you would expect, impossible to put into words. I was there with that Divine presence that was not anything that I could visibly see and describe, and with a brilliant orb of light…. 
 
 
 
 They said there were many things that they would show me, and they continued to do that. In fact, the whole higher-dimensional multiverse was this incredibly complex corrugated ball and all these lessons coming into me about it. Part of the lessons involved becoming all of what I was being shown. It was indescribable. 
 
 
 
 But then I would find myself—and time out there I can say is totally different from what we call time. There was access from out there to any part of our space/time and that made it difficult to understand a lot of these memories because we always try to sequence things and put them in linear form and description. That just really doesn’t work. 
 
 Everything that Alexander describes here and in his Newsweek article, including the parts I have left out, has been reported by DMT users. The similarity is uncanny. Here is how the late Terence McKenna described the prototypical DMT trance: 
 
 Under the influence of DMT, the world becomes an Arabian labyrinth, a palace, a more than possible Martian jewel, vast with motifs that flood the gaping mind with complex and wordless awe. Color and the sense of a reality-unlocking secret nearby pervade the experience. There is a sense of other times, and of one’s own infancy, and of wonder, wonder and more wonder. It is an audience with the alien nuncio. In the midst of this experience, apparently at the end of human history, guarding gates that seem surely to open on the howling maelstrom of the unspeakable emptiness between the stars, is the Aeon. The Aeon, as Heraclitus presciently observed, is a child at play with colored balls. Many diminutive beings are present there—the tykes, the self-transforming machine elves of hyperspace. Are they the children destined to be father to the man? One has the impression of entering into an ecology of souls that lies beyond the portals of what we naively call death. I do not know. Are they the synesthetic embodiment of ourselves as the Other, or of the Other as ourselves? Are they the elves lost to us since the fading of the magic light of childhood? Here is a tremendum barely to be told, an epiphany beyond our wildest dreams. Here is the realm of that which is stranger than we can suppose. Here is the mystery, alive, unscathed, still as new for us as when our ancestors lived it fifteen thousand summers ago. The tryptamine entities offer the gift of new language, they sing in pearly voices that rain down as colored petals and flow through the air like hot metal to become toys and such gifts as gods would give their children. The sense of emotional connection is terrifying and intense. The Mysteries revealed are real and if ever fully told will leave no stone upon another in the small world we have gone so ill in. This is not the mercurial world of the UFO, to be invoked from lonely hilltops; this is not the siren song of lost Atlantis wailing through the trailer courts of crack-crazed America. DMT is not one of our irrational illusions. I believe that what we experience in the presence of DMT is real news. It is a nearby dimension—frightening, transformative, and beyond our powers to imagine, and yet to be explored in the usual way. We must send fearless experts, whatever that may come to mean, to explore and to report on what they find. (Terence McKenna, Food of the Gods, pp. 258-259.) 
 
 Alexander believes that his E. coli-addled brain could not have produced his visions because they were too “intense,” too “hyper-real,” too “beautiful,” too “interactive,” and too drenched in significance for even a healthy brain to conjure. He also appears to think that despite their timeless quality, his visions could not have arisen in the minutes or hours during which his cortex (which surely never went off) switched back on. He clearly knows nothing about what people with working brains experience under the influence of psychedelics. Nor does he know that visions of the sort that McKenna describes, although they may seem to last for ages, require only a brief span of biological time. Unlike LSD and other long-acting psychedelics, DMT alters consciousness for merely a few minutes. Alexander would have had more than enough time to experience a visionary ecstasy as he was coming out of his coma (whether his cortex was rebooting or not). 
 
 Does Alexander know that DMT already exists in the brain as a neurotransmitter? Did his brain experience a surge of DMT release during his coma? This is pure speculation, of course, but it is a far more credible hypothesis than that his cortex “shut down,” freeing his soul to travel to another dimension. As one of his correspondents has already informed him, similar experiences can be had with ketamine, which is a surgical anesthetic that is occasionally used to protect a traumatized brain. Did Alexander by any chance receive ketamine while in the hospital? Would he even think it relevant if he had? His assertion that psychedelics like DMT and ketamine “do not explain the kind of clarity, the rich interactivity, the layer upon layer of understanding” he experienced is perhaps the most amazing thing he has said since he returned from heaven. Such compounds are universally understood to do the job. And most scientists believe that the reliable effects of psychedelics indicate that the brain is at the very least involved in the production of visionary states of the sort Alexander is talking about. 
 
 Again, there is nothing to be said against Alexander’s experience. It sounds perfectly sublime. And such ecstasies do tell us something about how good a human mind can feel. The problem is that the conclusions Alexander has drawn from his experience—he continually reminds us, as a scientist—are based on some very obvious errors in reasoning and gaps in his understanding. 
 
 Let me suggest that, whether or not heaven exists, Alexander sounds precisely how a scientist should not sound when he doesn’t know what he is talking about. And his article is not the sort of thing that the editors of a once-important magazine should publish if they hope to reclaim some measure of respect for their battered brand.
– When science journalist Carl Zimmer wrote a 2010 article in Discover magazine about English neurologist Adam Zeman's case study of a man who couldn't visualize people or things, the professor was approached by 21 people who saw themselves in the article and wanted to learn more. Now Zeman and colleagues at the University of Exeter Medical School are reporting in the journal Cortex that the condition could affect as many as 2.5% of the population. They're calling it "aphantasia," though Zeman insists in an interview with the BBC that it is not a disorder but rather a "variability of human experience" where most of us "spend our lives with imagery hovering somewhere in the mind's eye, which we inspect from time to time." Says one man of his childhood insomnia: "I couldn't see any sheep jumping over fences, there was nothing to count." Others with the condition can't visualize the faces of their friends and family. The newly described condition is something that affects some people from birth, which is different from the experience first described by Zeman in Discover about a patient who lost the ability to visualize after a heart procedure. In patients with congenital aphantasia, Zeman says that a network of regions distributed throughout the brain but implicated in visualization may function differently, not from a traumatic event but from birth. Similarly, people can be born with hyperaphantasia, or the ability to visualize in acute detail. To better understand the neurological underpinnings of this range of visual experiences, Zeman is working on a year-long project—The Eye’s Mind—that involves artist Susan Aldworth, art historian John Onians, and philosopher Fiona Macpherson. (Speaking of visualization, see why Roseanne Barr is going blind.)