Hallucinations

In Hallucinations, Oliver Sacks uses both personal experience and plenty of anecdotal evidence to illuminate the idea that hallucinations can occur in individuals as a result of any number of seemingly harmless conditions. Sacks uses a case study approach to delineate the different causes of hallucinations, shedding light on the idea that they are not symptoms of being "crazy". From Charles Bonnet Syndrome and Parkinson's disease to drug and exhaustion-induced hallucinations, Sacks examines the neural pathways involved in creating these perceptual phenomena. His vast clinical experience and background in hallucination-related conditions guides the journey through the fascinating world of altered cognition - something that I think makes his narrative particularly convincing. The message that Sacks wants you to take away from this book is that hallucinations are not indicative of a debilitating neurological illness; instead, they are simply "unwarranted" signals between synapses that break the threshold into consciousness. Every hallucination that is perceived by patients can be traced to transient synaptic signaling by numerous brain-imaging methods. There are real neurons that are conducting action potentials causes by neurotransmitter signaling, even if there isn't a sensory stimulus to cause these signals. It's as if the brain makes up its own stimuli and then it functions according to normal synaptic signaling.Because of his previous personal experience with hallucinations (described in detail throughout the book), Sacks is able to expose the truth about hallucinations. I think it is his personal observations and experiences, which he continuously elaborates on, that give readers the most insight into the misunderstood world of patients that experience hallucinations. He talks about how there are plenty of populations that experience hallucinations as a secondary effect of a medication that they are on or as a result of an otherwise "non-psychotic" disease. These include patients of Parkinson's disease and Charles Bonnet Syndrome. Sacks dedicates plenty of discussion to the idea that hallucinations are helpful in some peoples lives, having a much more beneficial effect than is popularly believed. Much of his work on the beneficial effects of hallucinations stems from his belief that hallucinations may have been a result of evolutionary pressures early in the development of consciousness. All of this is done to add to the notion that hallucinations should not be directly correlated with some type of psychosis.Sacks seems to believe that the best way to understand each of the broad categories of hallucinations he describes is to use first-hand accounts of patients he has been in contact with or treated. As a result of this belief, the book is made up entirely of anecdotal evidence about different patients experiences with hallucinations with his own commentary interspersed throughout the book. Although the different causes of hallucinations leads to different perceptual patterns, there is a lot of overlap in the discussion of the actual experiences associated with these patients' personal accounts. Because Sacks chooses to use only personal accounts, his discussion eventually becomes tedious and repetitive. It becomes difficult to try to conceptualize the differences between hallucinations and his descriptions seem to become contrived. If you were to read only one chapter of the book, the immense amount of detail given by Sacks could be seen as necessary to fully comprehend what is going on during hallucinations. However, my opinion is that trying to conceptualize every bit of information presented by Sacks can take away from the bigger picture that he is trying to create.In all, this book was as thorough a discussion of hallucinations as could be expected. I don't think I've ever read as detailed of a description of hallucinations as the ones that I found in this book. It illuminates the idea that hallucinations are a far more universal experience than normally believed. Although the analysis is thorough, more time could have been devoted to the underlying theory of hallucinations as well as clinical research done toward treating the negative effects of hallucinations. I think this book is good for the everyday reader and for the aspiring neuroscientist. There was no point in the book when I felt overwhelmed with scientific dialogue, nor did I find myself bored by redundancies or over-simplifications. I would give this book 4.5 out of 5 stars, being left with a greater understanding of hallucinations and consciousness as a whole.

ObjectiveDr. Oliver Sacks emphasizes the importance of categorizing hallucinations as symptoms of a puzzled or damaged brain that is trying to compensate the absence of a specific sensory input. This review aims to provide a detailed analysis of Oliver Sacks', "Hallucinations" which is a compendium of hallucinatory experiences faced by his patients.Overall OpinionAs an undergraduate student studying neuroscience, I chose this book to understand the complexity and pathophysiology of hallucinations, especially Tactile Hallucinations, and how it relates to the conscious mind. As a physician and a professor of Neurology at New York University School of Medicine, Dr. Sacks recounts the stories of his patients with great empathy and comprehension. I found the book very fascinating to read as it immerses the reader in the hallucinatory experiences of Dr. Sack's patients and it encourages the reader to think critically about the reason behind such tricks of the brains. This book not only narrates these hallucinatory experiences but also associates these manifestations to specific regions of the brain. Through this review, I wish to encourage everyone to read this book and acknowledge hallucinations as a problem of the brain rather than just a psychotic behavior of an individual.Synopsis of the BookIn chapter one, Dr. Sacks recalls the incident of an old woman named Rosalie who started seeing things when she was at her nursing home. Rosalie was blind and she had been hallucinating images of people with distorted faces and animals. She explaines that the images were not a dream but rather "like a movie". Dr. Sacks then attributed these symptoms to a condition called Charles Bonnet Syndrome. He emphasizes that her symptoms were not "psychiatric" rather a "reaction of the brain to the loss of eyesight". He explains that Charles Bonnet Syndrome is a very common condition and goes on to recount other patient's experiences of mild forms and severe forms of hallucinations in completely visually impaired or slightly visually impaired individuals. In chapter two and chapter nine, Dr. Sacks depicts the importance of the brain in visual hallucinations. He describes an experiment done by William Bexton in order to understand the effects of total sensory deprivation in fourteen college students. The results of the experiment showed that these students started experiencing heightened visual, auditory and kinesthetic hallucinations. With the help of functional magnetic resonance imaging (fMRI), researches were able to attribute visual hallucinations to the activity in the primary visual cortex of the occipital lobe and fusiform gyrus in the temporal lobe. Even damage to one half of the occipital lobe can result in visual impairment of one eye leading to hallucinations. In chapter seven, Dr. Sacks explains his own experience of his migraines that caused visual hallucinations of geometric shapes and bright colors.Anosmic patients, people who have lost their sense of smell, can have olfactory hallucinations as reiterated by Dr. Oliver Sacks in chapter three. He recounts the experience of several patients who have lost their sense of smell due to a damage of their olfactory tracts. One particular instance includes the experience of a Canadian woman, Mary B, who suffered from unpleasant smells after operation under general anesthesia. Tomatoes started smelling metallic and cottage cheese like sour milk. She had to pick and choose specific food to eat during all her meals. Auditory Hallucinations (Chapter 4) are particularly related to psychiatric patients especially schizophrenic patients and have been associated with the abnormal activation of the primary auditory cortex. Dr. Sacks suggest that auditory hallucinations are the result of "failure to recognize internally generated speech as one's own." Additionally, phantom limbs are a type of tactile hallucinations as Dr. Sack explains in chapter fifteen. He explains phantoms limbs as a voluntary type of hallucination in patients with an amputated part of their body. Epilepsy and drug induced (Chapter 6, 8, 10 and 13) hallucination is caused by high activation of specific regions of the brain that can excite stored memories and emotions. Hallucinations due to sleep deprivation and Parkinson's disease are emphasized by Dr. Sacks in chapters 5, 11 and 12. These diseases encounter a combination of visual, auditory, olfaction and tactile hallucination and it is difficult to pinpoint these hallucinations to one part of the brain.Style and Structure of the BookThe book was divided into fifteen chapters each of which emphasized on one particular cause of hallucinations in patients. The book was easy to read from beginning to end as the use of imagery in the book immersed the reader into the patient's hallucinatory experience. In each chapter, Dr. Sacks narrated several experiences, introduced the history of the particular cause of that hallucination, associated these causes with specific regions in the brain and asserted his own interpretation of these hallucinations. Moreover, the portrayal of real world patients and Dr. Sacks' empathy and comprehension towards their condition gives the book a certain kind of credibility in holding the attention of the reader.Opinion on Specific PartsI was intrigued by most of the hallucinatory experiences that were explained in the book. However, there were a few specific parts of the book that I was enthralled in. The clinical case study of phantom limbs was of great significance as almost all patients with an amputated part of their body suffered from the pain of a phantom limb. These hallucinations are different from all other hallucinations because they can be controlled voluntarily. Dr. Sacks reiterated V.S. Ramachandran's concept that these tactile hallucinations were due to "learned" paralysis in which the brain is in conflict of making decisions and thus, abandons the motor commands sent to the phantom limbs.Also, it was interesting to learn that visual hallucinations are very common in the world and we do not know about its prevalence because individuals who experience hallucinations are scared to be labeled by the society as delusional. Therefore, the book provides detailed history and case studies to associate hallucination to a particular brain region.It was interesting to note that hallucinations can be caused by migraines, emotions, beliefs, complete sensory deprivation and lack of sleep through the activation of the regions of the brain involved in the functioning of various sensory inputs. People with severe migraines tend to hallucinate geometric shapes and colors due to heightened activity of their primary visual cortex. In Charles Bonnet syndrome, complete deprivation of the visual senses leads to hallucination of faces and this is recognized by the activity of the brain region called the fusiform gyrus in the temporal lobe. Moreover, patients who suffer from Parkinson's disease have hallucination caused by their medication. Dr. Sacks' experiences of hallucination from drug intake and migraines provide a credible source of such incidents.Useful/Interesting Quotes"...hallucinations are percepts arising in the absence of external reality- seeing things or hearing things that are not there.""Do the geometric patterns seen in migraine and other conditions prefigure the motifs of Aboriginal art? Did Lilliputian hallucinations (which are not uncommon) give rise to the elves, imps, leprechauns and fairies in our folklore? Do the terrifying hallucinations of the nightmare, being ridden and suffocated by a malign presence, play a part in generating our concepts of demons and witches or malignant aliens? Do `ecstatic' seizures, such as Dostoyevsky had, play a part in generating our sense of the divine?"Summary of reviewAltogether, this book is an easy read with its elaborate yet captivating narratives of Dr. Oliver Sacks' patients who experienced hallucinations. It was entertaining and at the same time it was plausible. I like the way Dr. Sacks categorized the book based on different causes of hallucinations and the title of each chapter added to the mystery of the characteristics of the hallucination he was emphasizing in the same chapter. Although the book emphasized a lot on specific types of hallucination, it failed to give a more detailed description of the pathophysiology of the hallucination especially with respect to different brain regions. Moreover, this book is a great stepping-stone towards new findings in clinical medicine regarding hallucination, which was once thought to be purely under psychiatry. It emphasizes hallucinations as being very common in most people's lives today.RecommendationI would recommend this book to anyone who is interested in learning about mind perceptions in patients who experience hallucinations. Dr. Oliver Sacks has quoted as well as cited several experts in Neuroscience who has analyzed the sensation and perception of the brain as it relates to hallucinations making it a credible source for future analysis of hallucinatory experiences. Although the book does not give a lot of detail on the pathophysiology of hallucinations, it can be used to delve deep into the different types and subtypes of hallucination in patients who have some kind of neurological condition.

The works of Oliver Sacks are standard works for anyone interested in the workings of the human brain. But they are entertaining and enlightening for most of us. The most interesting aspect of his writing is the way he uses odd brain states to speculate on what they tell us about the workings of the normal brain – if there is any meaning to the word “normal.”“Hallucinations” are things we sense (see, hear, feel, smell, etc.) while we are awake that no one else perceives to be there. If you asked most people what they think “hallucination” means, they assume that it refers to someone who is schizophrenic or on illegal drugs. But Sacks points out that there are many other conditions which cause hallucinations. Nearly all of us may have some experience in our life which qualifies for that definition. Epilepsy, migraine headaches, brain tumors, concussions, strokes, or other forms of brain injury typically cause visions and distortions of reality, from flashing lights to visions of people appearing before us. Even more common are the brief aural or visual hallucinations that most of us have one time or another just as we are falling asleep or waking up. This might include hearing someone call your name or someone seeming to be beside you in the bed, when the house is actually empty.Sacks’s book should be read not just by medical professionals but by anyone who works with patients -- in nursing homes, medical offices, rehab centers, or with your own relatives – and by anyone who anticipates BECOMING a patient. Many of the people reading this review will have hallucinations of different kinds as they get older.Sacks also writes from personal experience. He is subject to migraines himself (the subject of his first book) and has had many hallucinations related to that condition. He also experimented with drugs in college and has tales to tell about that. And he briefly discusses an experience where after a severe leg injury and surgery, he felt like his leg had disappeared completely and some alien thing put in its place (written about at length in the book *A Leg to Stand On*).Not only is this book fascinating, it might save your life or a relative’s life someday. And just maybe the next time you or I see a person talking to an invisible friend or telling you about the music they hear playing, we might give consideration to the thought that “that person is ill” rather than “that person is crazy.”

I rarely preorder books, but that was before I heard Oliver Sacks was getting ready to publish 'Hallucinations'. For those who are unfamiliar, he is one of the few celebrated neuropsychologists / popular medical writers who is taken seriously by the scientific community due to his airtight research but also willing to break the taboos of sharing his own personal drug history and also discussing hallucinations and delusions outside of the trap of "mental illness" - as a unique aspect of mental life that for some people can be terrifying and for others can be interesting or even pleasant, helping to erase the stigma. I finally got the chance to read through 'Hallucinations' and I highly recommend it to anyone who is interested in psychology or neuroscience, it's written in layman's terms with mostly patient's own reports so you don't need more than a basic background in neuropsych to get the gist.A prior familiarity with Sacks is not necessary but helpful, as it builds on his past work - one of the most heartbreaking things for me about Awakenings was the heartbreaking choice of whether to allow the Parkinsonian encephalitis patients to keep taking L-Dopa (which allowed them to leave the catatonic state and finally be active and talk and live their lives again) despite the fact that it caused hallucinations and erratic, sometimes aggressive urges, or to return them to their living deaths where they could be easily managed like coma patients. This is often the dilemma of the mentally ill patient who is deciding whether to take their meds or not - is it really better to be in a stupor, sleeping all day long and only 'living' in the sense that their heads are too cloudy to commit suicide, then to have to listen to and try to ignore the voices in their head which are often deeply tied to creativity and spirituality? To the nurses, it is far easier to deal with the catatonic patient, in the real world, the logic is often "at least they aren't outside committing crimes", but with a reform of the mental health system including encouraging patients to write books and make artwork exploring their insanity, and organized sports and outdoor trips (or fishing trips a la Kesey) to help manage their anger before it becomes violent, allowing hallucinations to become "the devil we know, not the devil we don't".

I've been a fan of Dr. Sack's books for a very long time, and recommended them to my medical and nursing students. The craftsmanship and extraordinary stories that always seem to come into Sack's professional life make him into an Indiana Jones of the mind.But I should say this later book isn't in the same league. Perhaps there's no unifying principle to sort causes and effects on this poorly understood corner of Neurology (the author makes a paltry effort with the Charles Bonnet Syndrome). Or perhaps there are so many scattered types of phenomena which qualify for hallucinatory that putting them together makes us feel like there's no reality--sort of Freud trapped into The Matrix--and anything is possible. Or maybe Dr. Sacks has seen so much weird stuff that he goes over material which questions the bases of perception like a doctor deciding if we have a cold.I'm not saying that the book isn't the best possible effort given its subject, just that the complexity of the underlying material can overwhelm the reader. Still, there's a lot of wondrous and fascinating stuff to be found between the covers--for me, a love-making hallucination with a daily appointment takes the cake.All of Dr. Sack's books come alive when he describes his personal experiences. And `Hallucinations' shines when the author undertakes an extraordinary (and at times harrowing) quest to try all kinds of hallucinogenic drugs. Considering how much he'd tried, and how good he looks--at almost eighty--in the back-cover's picture, the book could be an unintended advertisement for drug experimentation.The sheer quality of the book's research (compiling a huge database of contemporary and historical cases) and Sack's masterful writing makes it difficult to come hard on him for the result. But like a hallucination, this book comes and goes slowly, painfully, living a dreadful empty feeling that one doesn't really understand anything about the mind. A grand-master of neuroscience as Dr. Sacks should've been able to help us more.

Hallucinations permits each one of us to step into our inner lives. Now that pharmaceuticals have overtaken street drugs with deleterious effects on our overall American population, Oliver Sacks offers insights that should become common knowledge for both adults and juveniles. I widely share Sacks broad experiences with hallucinations and did not find his work to be "tedious" as some reviewers have remarked. One can easily skim through examples that are familiar and still appreciate the braod thrust of this work.As a retired professional who has worked with chemically addicted populations in the criminal justice system, I strongly recommend this book to reoovering addicts and students preparing to work in social work or law enforcement capacities. Hallucinations is loaded with practical, first-hand insights that will save both addicts and behavioral science students considerable time trying to understand humanitiy's flaws of cnsciousness. I agree with Sacks that first hand knowledge of one's subject matter is critical, and this knowledge he supplies in abundance. As a professional treatment provider, teacher and researcher with addicted populations, I am quite confident that service providers and addicts themselves will benefit considerably from this reading. I am also reasonably sure that addicts motivated to commit suicide and social service personnel who can help prevent this tragic outcome, will have new ammunition if they digest Hallucinations. Glen Just, Ph.D.

Hallucinations by Oliver Sacks"Hallucinations" is a fascinating book of what Dr. Sacks considers a natural history of anthology of hallucinations. It covers a wide variety of hallucinations through the eyes of those who have them and the impact it has on their lives. Dr. Sacks shares those vivid experiences with the readers but at times it can be overwhelming and hard to follow. This psychedelic 354-page includes the following fifteen chapters: 1. Silent Multitudes: Charles Bonnet Syndrome, 2. The Prisoner's Cinema: Sensory Deprivation, 3. A Few Nanograms of Wine: Hallucinatory Smells, 4. Hearing Things, 5. The Illusions of Parkinsonism, 6. Altered States, 7. Patterns: Visual Migraines, 8. The "Sacred" Disease, 9. Bisected: Hallucinations in the Half-Field, 10. Delirious, 11. On the Threshold of Sleep, 12. Narcolepsy of Night Hags, 13. The Haunted Mind, 14. Dopplegangers: Hallucinating Oneself, and 15. Phantoms, Shadows, and Sensory Ghosts.Positives:1. Engaging prose, well-researched book on a variety of hallucinations.2. Dr. Sacks is a master of his profession and a very accomplished author.3. A very good format. Each chapter covers a category of hallucination.4. A good introductory chapter that covers the essence of the book. "Hallucination is a unique and special category of consciousness and mental life".5. Full of first-hand accounts and historical accounts of hallucinations. The accounts vary from the common to the bizarre.6. Hallucinations among the blind. The Charles Bonnet Syndrome (CBS). "CBS hallucinations are often described as having dazzling, intense color or a fineness and richness of detail far beyond anything one sees with the eyes."7. The effects of sensory deprivation. "There is even a special term for the trains of brilliantly colored and varied hallucinations which come to console or torment those kept in isolation or darkness: `the prisoner's cinema.'"8. Hallucinations come in many forms including hallucinatory smells. "Hallucination of particularly vile smells is called cacosmia."9. Misconceptions. "In the popular imagination, though, hallucinatory voices are almost synonymous with schizophrenia--a great misconception, for most people who do hear voices are not schizophrenic."10. Interesting observations. "Music calls upon many more areas of the brain than any other activity--one reason why music therapy is useful for such a wide variety of conditions."11. Parkinson's disease as it relates to hallucinations. "...perhaps a third or more of those being treated for Parkinson's experienced hallucinations."12. Chemicals and altered states. "But drugs offer a shortcut; they promise transcendence on demand. These shortcuts are possible because certain chemicals can directly stimulate many complex brain functions."13. Migraine auras, who knew? "She explained that auras like mine were due to a sort of electrical disturbance like a wave passing across the visual parts of the brain."14. A fascinating look at "hyper-religiosity". "More than any other sort of seizure, ecstatic seizures may be felt as epiphanies or revelations of a deeper reality." A bonus quote of historical worth, "None of these is conclusive, but they do suggest, at least, that Joan of Arc may have had temporal lobe epilepsy with ecstatic auras."15. Some of the causes of hallucinations are discussed. "...even a "little" occipital lobe stroke can evoke striking, though transient, visual hallucinations."16. The impact of delirium. "Delirium may produce musical hallucinations." "Fevers are perhaps the commonest cause of delirium, but there may be a less obvious metabolic or toxic cause."17. A look at dreams. "Dreams come in episodes, not flashes; they have a continuity, a coherence, a narrative, a theme. One is a participant or a participant-observer in one's dreams, whereas with hypnagogia, one is merely a spectator." "The "mare" in "nightmare" originally referred to a demonic woman who suffocated sleepers by lying on their chests (she was called "Old Hag" in Newfoundland)." Great stuff!18. The trauma of war (severe stress). An important topic. "Such chronic traumatic encephalopathy, along with the psychological trauma of war and injury, has been linked to the rising incidence of suicide among veterans."19. Out of body experiences. "Out-of-body experiences may occur when specific regions of the brain are stimulated in the course of a seizure or a migraine, as well as with electrical stimulation of the cortex." "They may occur with drug experiences and in self-induced trances. OBEs can also occur when the brain is not receiving enough blood, as may happen if there is a cardiac arrest or arrhythmia, massive blood loss, or shock."20. Phantom limbs. Test this for yourself...very interesting. "Phantom limbs are hallucinations insofar as they are perceptions of something that has no existence in the outside world, but they are not quite comparable to hallucinations of sight and sound."21. Links and a very helpful bibliography.Negatives:1. This is a difficult book to follow at times. Part of it has to do with the complexity of the condition but I also feel that Dr. Sacks overwhelms the readers with psychedelic descriptions at a frenetic pace.2. This book is uneven in that that it describes the various types of hallucinations with a luxury of details (first-hand accounts) but the science though present is not as apparent. Granted this book is intended for the masses but I wanted to know more about the potential causes.3. This book warranted a table that summarized the different types of hallucinations and symptoms. It would have been very helpful.4. It's the type of book that after reading you are not really sure what you got out of it. Luckily, there are no tests.In summary, a bit overwhelming and frenetic at times but overall I enjoyed the book. It's the type of book that after reading you have a better understanding of the wide range of variety of hallucinations but you are not able to intelligently provide details on how they differ necessarily. It's an interesting book whose strengths reside in the first-hand description of a wide variety of hallucinations. The science behind the hallucinations though present lags the same attention. That being said, I recommend it!Further recommendations: "The Man Who Mistook His Wife For A Hat: And Other Clinical Tales" and "Musicophilia: Tales of Music and the Brain, Revised and Expanded Edition" by the same author, "Phantoms in the Brain: Probing the Mysteries of the Human Mind" and "The Tell-Tale Brain: A Neuroscientist's Quest for What Makes Us Human" by V.S. Ramachandran, "Dreamland: Adventures in the Strange Science of Sleep" by David K. Randall, "How the Mind Works" by Steven Pinker, "Predictably Irrational, Revised and Expanded Edition: The Hidden Forces That Shape Our Decisions" by Dan Ariely, "Incognito: The Secret Lives of the Brain" by David Eagleman, "Mistakes Were Made (but not by me)" by Carol Tavris and Elliot Aronson, "Paranormality: Why we see what isn't there" by Richard Wiseman, "The Believing Brain: From Ghosts and Gods to Politics and Conspiracies---How We Construct Beliefs and Reinforce Them as Truths by Shermer, Michael unknown Edition [Hardcover(2011)]" by Michael Shermer, and "Subliminal: How Your Unconscious Mind Rules Your Behavior (Vintage)" by Leonard Mlodinow.

A tour de force by Oliver Sacks. Drawing deeply on scientific insight, literature and his own quite extensive personal experience of the use of hallucinogenic drugs Sacks complies perhaps the most important book on hallucinations since Albert Hoffman's "L.S.D.: My Problem Child".Sacks, across numerous essays, examines hallucinations from a number of vantage points allowing the reader the closest experience of hallucination they are liable to have short of actually hallucinating themselves. Indeed as Sacks shows hallucinations are actually quite common-place, rather than being the sign of some kind of perceptual defect or result / side-effect of drugs of differing kinds. We, or at least most of us, have - at some time or another - hallucinated.Hallucinations have been used to provide proof of contact with the Gods or demons, they have provoked - or are a symptom of - mental breakdowns and they have been the inspiration for any number of works of art - visual, auditory and so on. Indeed Sacks shows how hallucinations are far more common than one might think, rather than being a marginal phenomena of interest only to Neurologists, Psychologist, Anthropologists amongst other academic discplines and of course "thrill seekers / drug users".At the very least "Hallucinations" provides justification for considerably more research to be conducted into hallucinations: the triggers for; the short and long term effects of; and the interpretation of them from ontological and psychological perspectives.

Great book this is my second time reading it and is great

Biological perspective- showcases a variety of patient history and experiences which astounds the reader! The description and detail of every situation is as precise as it can get.WORTH THE MONEY!I recommend it to everyone! (:

To be read! it is interesting in order to understand us, our brain and science, which is not always easy to be understood.

The book is mostly a collection of anecdotes ordered by different causes of hallucinations.Oliver Sacks obviously had a lot of empathy for his patients and fellow human beings, and he wrote well.It can at times be a bit repetitive, but it's an easy read and overall a nice book.

Oliver Sacks is one of those gifted writers who satifies your curiosities and leaves you a lot wiser after reading his books