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.

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.

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.”

This is another great read by Oliver Sacks. In this one, he pulls together information on hallucinations. His descriptions run the gamut, and include hallucinations that are visual, auditory, olfactory and sensing a "presence" close to one. Some described are interactive and others are static. While hallucinations are widely associated with schizophrenia, Sacks does not dwell on those. Hallucinations are experienced by a wide variety of people under varying circumstances. Total or complete blindness, loss or impairment of hearing, loss of a limb can trigger them. They can occur at the edges of sleep, whether falling asleep or waking. And the interpretation of the individual can vary from mundane to frightening, from religious or ethereal to corporeal and tangible. As in other books, Sacks explores the science behind the experiences as well as the personal impact these have on the individuals. With modern scientific tools, the areas of the brain involved in each type of hallucination have been defined. He also looks at literature, both fictional and historical, for examples of probable hallucinations. All in all, a fascinating read. .

Dr Sacks' book is specifically delineating the circumstances in which hallucinations are experienced outside of psychosis and dreaming. I found the neurological specifications of the phenomena to be fascinating. Dr. Sacks has a wonderful facility in the phrasing of esoteric neurological symptoms and malfunction in such a way that is accesable to the non-medical reader. I had two issues with this book. The first has been noted in a review already posted. I find the long description of the hallucinations to be heavy reading after a while. I agree it is a bit like listening to another person's dreams, which tend to lack the immediacy to the listener. I especially found it tedious to review the author's experiences with drugs that indue hallucinations. This is a subject very heavily covered in extant literature. Second, he allows only cursory credance to the concept that any spiritual experiences may be caused by anything other than organic function. He notes that James had allowed that practitioners of spritualism may believe their experiences to be true. While I understand that this is the premise of the book, still it lacks some depth of possibility. Given these caveats, I think this is a worthwhile reading experience. Certainly this book expands the world of hallucinations outside of psychotic cause. Certainly this is important for those people who experience these phenomena to know possible medical issue both for their own peace of mind and for the motivation to seek help. Therefore I would recommend this book.

Hallucinations provide a window into another world. A world where strangers visit, angels reside, and landscapes reverberate with all sorts of strange qualities. Walking alongside us through this world is Sacks and one couldn't ask for a better guide. Starting us off, Sacks introduces the reader to Charles Bonnet Syndrome where a lack of visual stimulus leads to hallucinations. The visual area of the brain, in cases of blindness of various degrees, "overcompensates" and can produce panoply of imagery. Sufferers often see images of people totally unrelated to their lives engaged in various activities also unrelated to memories and experiences. One elderly lady would see a procession dressed in Asian garb silently glide through her visual field. Syndromes such as this, Sacks tells us, show how active our perceptual systems are when they are engaged in the act of perceiving. Sacks guides us through many types of hallucinations, not just the visual. The phenomena of auditory, olfactory, and tactile hallucinations are also covered in engrossing detail. They are also differentiated such as between patients with neurological damage and problems and between that caused by psychotropic substances. One case is recounted here from a man experiencing LSD hallucinations. The change in perception and how powerfully these alter our "world" is truly astounding. A type of hallucination that I have had personal experience with is also covered in the book. Imagine you are 10 years old and that your worst fear is werewolves. Everything about these imaginary creatures terrifies you. Then imagine that you find yourself awake in the early morning dark one day, unable to move with sleep paralysis. You watch as a werewolf enters through the doorway and leaps onto your bed, pinning you down with a bare-fanged muzzle snarling and dripping hot drool on your face. Everything about this experience screams that it is real - down to the very way that you can see the details of skin and fur in close relief inches from your nose. Needless to say, this was an extraordinary experience. However, the werewolf was only there for about 15 seconds before I was able to shake the sleep paralysis. The creature that had been poised over me in a murderous rage fades and vanishes. Reading this book I came to learn that this was an instance of two phenomena that often accompany one another: sleep paralysis and hypnopompic hallucinations. The aforementioned account is the only one that I have had that left a lasting impression. Sacks also tells us that these are often singular experiences. If you want to know more about these mental and perceptual phenomena, more about how the human brain/mind works, and be pleased by good writing along the way, look no further than this book.

Hallucinations by Oliver Sacks allows the reader to glimpse into the mysterious world of hallucinations by exploring the many causes behind them. Sacks, a neurologist, guides the reader through multiple types of hallucinatory experiences with examples from real people. The personal stories help bring the hallucinations to life and prevent the scientific explanations from getting too boring. Interesting topics such as the connections between the paranormal and hallucinations are discussed. Sacks is able to discuss complex topics with a reader with no neuroscience background and goes beyond explaining by using examples and detail to make the book an enjoyable read. Overall I would give this book 4 out of 5 stars. Sacks makes sure to highlight important characteristics about hallucinations. For example he points out that hallucinations differ from dreams. Hallucinations still allow a person to keep their insight and realize that what they're seeing isn't real; which is unlikely while dreaming. Sacks also discusses how hallucinations rarely lead to delusions because the individual realizes they're hallucinating. They aren't an indication of psychoses and are much more common than realized. Sacks also explains that when doing PET scans, different areas of the brain are active during a hallucination compared to imagining something. This means that theoretically patients cannot make up their hallucinatory experiences; because doctors can watch them unfold in the brain as they happen. Hallucinations can be visual, olfactory, auditory, tactile or multisensory. A hallucination is raw and is not constrained by higher brain structures. Therefore hallucinations of musical scores and words rarely make sense, as they aren't bound by grammar or rules. Sacks is able to admit limitations in research and does not try to make assumptions without support. When discussing auditory hallucinations he suggests it's abnormal activity in the primary auditory cortex. He does admit, though, that psychiatric patients are the subjects of most of the research about auditory hallucinations. By discussing these important characteristics Sacks sets the stage to move on to specific hallucinatory experiences. Many different types of hallucinations and their causes are discussed in the book. Sacks starts off explaining that loss of normal input to a brain region increases spontaneous activity in that area. Those who experience visual hallucinations from loss of eyesight experience simple to complex faces, shapes, and words. These can be in blind fields or superimposed on vision, as in Charles Bonnet Syndrome. Sensory deprivation is not the only cause of spontaneous activity within the brain. Sacks moves on to explain how over-activity in the brain causes hallucinations. For example, seizures are an electrical discharge within the brain and cause hallucinations. Seizures can have an epileptic focus, which effects only certain areas in the brain. Doctors can tell where an epileptic focus is based on the type of hallucination. Different states of mind can also cause hallucinations. Greif can cause hallucinations and many have had multisensory hallucinatory experiences after loss. One particular example described a person in whom just remembering a family member brought on their smell. Sacks discusses that hallucinations are common when we are between the state of sleeping and wakefulness. Hypnopompic hallucinations occur while waking and often "threaten" the hallucinator. An actual person doesn't need to be seen; for example some people hallucinated only a presence. Sacks suggests that these type of hallucinations along with grief hallucinations may contribute to paranormal accounts. Sacks discusses various substances cultures have used throughout history such as LSD, opium, hashish, and extract from mescal or peyote cactus. Sacks did well in keeping connected topics together to help bring together a full picture of many different causes behind hallucinations. Overall, I enjoyed reading this book because of content and organization. Sacks does a good job covering a wide range of hallucinations and their causes. The hallucinations are organized based on their underlying cause which helps the reader understand the concepts because it doesn't jump around. He provides specific examples for each type of hallucination allowing a richer reading experience because the reader can connect more. When reading about a woman's hallucinations caused by Charles Bonnet Syndrome one could picture the extravagantly dressed parade she saw. Although the wide range of hallucinations he covered was entertaining, while reading I felt that at times he was just listing off case studies rather than expanding on them. If Sacks went into more detail than a basic understanding about specific hallucination types it would feel less like a list. At times it felt he would give a brief description of an individual's hallucination then move on to a different one, which left the reader wanting more. This aspect of the book does make it good if the reader does not wish to explore that far into detail. Sacks did well in explaining hard concepts to readers that had no background information. While talking about the angular gyrus's role in out of body experiences he discusses that is plays a role in body image thus connecting a harder term with an easy explanation of relevance. He employs this strategy throughout the book. All of these characteristics helped the reader get an understanding of wide variety of hallucinations while being entertained with real life examples. Hallucinations by Oliver Sacks was a well written overview into the mysterious world of hallucinations. Sacks covers many different types of hallucinations and their associated causes. He presents many different case studies and research to explain what causes hallucinations. Overall he did a good job explaining complex concepts in a way the average person could understand. The book did feel somewhat like a list of examples which was disappointing but could easily be improved by further explanations. Sacks used a good balance of science with a component of personality to write this book making his latest work a good read. I give this book four out of five stars and would recommend it to a friend.

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".