The Nocturnal Brain

The Nocturnal Brain

Author: Guy Leschziner


This is perhaps the most compelling book to come out of the extraordinary world of sleep disorders. The author, clearly a master of narrative non-fiction, explores the colourful spectrum of nighttime phenomena which he describes as ‘the dramatic, terrifying, illuminating, poignant and sometimes amusing‘ (page 3). His objective, in depicting these intriguing diseases, was to open a window into ‘the role of normal sleep in maintaining the brain’, and for readers to ‘come to know a little about how we ourselves are affected by our sleep’ (pages 3 and 12). With gripping case studies, the book succeeds in exposing the darker side of our nightly tranquil hibernations, revealing a repository of terrifying diseases. With harrowing symptoms such as ‘shouts, jerks, snores, twitches…or even no sleep at all’, the book makes readers appreciate the value of tranquil slumber (page 1).

Bluesnose-Sleeping Iron Giant-Bordesley Green. Elliott Brown on Flickr.

The stories in this book, from the dramatic to the tragic, reflect the whole array of sleep disorders. The manifestations are as curious as they are diverse, with victims ranging ‘from those who sleep too much, to those who sleep too little, and those who sleep at the wrong time or in the wrong way‘ (page 314). The author narrates every story with unimpeachable prose, painting a humane picture of each nocturnal sufferer, and explaining the underlying mechanism driving the disease process. Take for example the fascinating case of long-suffering sleepwalker Jackie, whose complex nocturnal activities include riding her motorcycle, a feat that is possible only because she can get into a ‘dual brain state of simultaneous wake and sleep‘ (pages 38-41). Another spellbinding case is that of Janice, whose rare and multifaceted form of epilepsy arises from the insular part of the brain, and this location explains why she manifests with a recurrent sensation of choking. With this all-encompassing style, the author painted a complete picture of each disease he dissected.

By Pieter Bruegel the Elder – The Yorck Project (2002) 10.000 Meisterwerke der Malerei (DVD-ROM), distributed by DIRECTMEDIA Publishing GmbH. ISBN: 3936122202., Public Domain, Link

What clearly marks this book out is the author’s knack of breathing life into otherwise mundane topics. This is perhaps best demonstrated in his treatment of insomnia, a topic he animated with uplifting prose. He wrote, for example, that ‘there is nothing quite like the loneliness of the insomniac, awake in the middle of the night while the rest of the world sleeps‘, adding that insomniacs ‘live in dread of the night ahead’, and ‘see their bedroom as a place of torment, an instrument of torture‘ (pages 289 and 295). Another distinctive feature of the author’s narrative is his  flair for infusing mystery and adventure into every story. Take the riveting tale of Vincent who at first seems to be suffering from delayed sleep phase syndrome, a disorder of light-sensitivity in which the ‘internal body clock seemed to be set at the wrong time‘. However, in an ingenious plot twist worthy of an Agatha Christie thriller, the author reveals a much rarer alternative diagnosis; it is worth reading the book just to find out the denouement (pages 17- 24). The case of Robert takes an even more sinister tone as a full blown crime thriller with a hint of gaslighting (page 107). The law and order theme is further explored with disorders such as sexosmnia, a curious disease where the patient may commit rape whilst completely asleep; this is contrasted with the rather gruesome but true-life homicidal sleepwalking case of Kenneth Parks (pages 177, 201, and 208). 

By Arthur Rackham Link

Perhaps the most beneficial feature of this book is its emphasis on the importance of normal sleep to good health. With this public health perspective in mind, the author pointed out the dangers of many banal leisure activities and work pursuits. Examples here include the hazard of ‘regular exposure to light at night‘, a rather ubiquitous activity which may however weaken the body’s resistance to cancer‘; and the peril of shift-work, which may increase the risk of medical disorders such as diabetes (pages 30-31). Other important sleep-related health threats addressed in the book include the risk of hypertension and stroke in people with restless legs syndrome; the risk of developing narcolepsy following the H1N1 vaccine; and the risk of neurodegenerative disorders such as Parkinson’s disease in people who suffer with REM sleep behaviour disorder (pages 160, 128, and 65-68). Doctors will be particularly pleased with the extensive sprinkling of cutting-edge, preventative medicine information, such as the risk of dementia with the use of benzodiazepines (page 301).

Starry ky. Danny Thomson on Flickr.

Beyond enthralling tales, the book is an archive of endlessly helpful medical information; a representative example is the fact that the circadian rhythm, mediated by melatonin, may be disrupted by environmental influences or zeitgebers such as light (pages 18-27). The book is also full of many revealing statistics, for example 80-90% of people with restless legs syndrome also suffer with periodic limb movements in sleep (pages 38 and 147).  The author also dispelled many misconceptions about sleep, for example, contrary to conventional wisdom, ‘dreaming in non-REM sleep is not unusual at all, although the content of the dreams is different’ (page 47). He enhanced his narrative with many interesting trivia, such as ‘certain animals like dolphins, seals and birds can sleep with one half of their brain at a time’, and REM sleep behaviour disorder is ‘one of the few medical conditions described in animals before humans’ (pages 39 and 65). Neurologists, like the author, will find a lot of the information in the book invaluable to their clinical practice; examples are the fact that cataplexy may occur with ‘absolutely no other features of narcolepsy‘, and the drug topiramate is effective in the treatment of sleep related eating disorder (pages 114 and 229)

By BodyParts3D/Anatomography by DBCLS – Anatomography [1], CC BY-SA 2.1 jp, Link
The excellence of the book as an interesting case series does not overshadow its merit as a thoroughly researched piece of work. In this regard, the author cited what is essentially a Who’s Who of sleep medicine, from Nathaniel Kleitman, ‘one of the founding fathers of modern sleep science’, to Eugene Aserinsky, ‘one of the discoverers of REM sleep’; from William Dement, ‘one of the other grandfather’s of sleep research’, to Emmanuel Mignot, the sleep specialist who identified the cause of narcolepsy. He also referenced dream expert Meir Kryger, and REM sleep expert Matthew Walker (pages 18, 62, 63, 254, 267, and 269). The book also made wider mention of foremost neurologists such as Jean-Martin Charcot, Joseph Babinski, Gilles de la Tourette, Constantin von Economo, and V. S. Ramachandran (pages 96, 116 and 191). The author complemented his narrative with frequent references to artworks such as the Hysteria painting by Pierre Brouillet, and The Nightmare by Henry Fuseli (pages 95-96 and 186). 

By Henry Fuseliwartburg.eduimage, Public Domain, Link



This book has succeeded in a remarkable way in bringing the nightly world of sleep disorders into the limelight. Revolving around gripping and enlightening stories, the book describes life-altering diseases, and explains the brain dysfunction driving them. With easy and delightful narrative, the author emphasised the paramount importance of sleep hygiene, highlighting the detrimental and fatal consequences of disordered sleep. The author’s prose is fast paced and laced with interesting facts and helpful recommendations. My only criticism is the rather long retelling of the story of the famous neuroscience subject, Phineas Gage; fascinating as it was, the anecdote did not appear to be significantly relevant to the subject of sleep disorders. That aside, there is little else to criticise about this excellent book.

Overall assessment

This is a comprehensive book on the diverse manifestations of sleep disorders, and the importance of sleep to health. The research is detailed and the cases portrayed are explored in depth. The lessons are relevant to all aspects of healthcare, and I recommend it to all doctors.

Book details

Publisher, Place, Year: Simon and Schuster, London, 2019
Number of chapters: 14
Number of pages: 353
ISBN: 978-1-4711-7635-7
Star rating: 5
Price: £9.10


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