New Book by Dr. Patrick McNamara – The Neuroscience of Sleep and Dreams, 2nd Ed.
The Neuroscience of Sleep and Dreams (2nd ed.), by Patrick McNamara, Cambridge University Press: 2023
Project Co-Leader Dr. Patrick McNamara announces a new book, released in 2023
From the Preface:
This introduction to the neuroscience of sleep and dreams is part of the Cambridge Fundamentals of Neuroscience in Psychology series published by Cambridge University Press. The goal of this series is to introduce readers to the use of neuroscience methods and research to inform psychological questions. A key theme, therefore, of this book, will be to introduce readers to the use of neuroscience methods and research in order to inform readers both about the basic science of sleep and dreams and to illuminate psychological questions that arise around sleep and dreams. This book can serve as a supplemental textbook in college/university courses such as Brain and Behavior, Psychopharmacology, Neuropsychology, Behavioral Neuroscience, Psychology of Dreams, Physiological Psychology and as a trade book for educated lay people, and/or as a main textbook in a college/university course or seminar at the advanced undergraduate level or the graduate level (along with supplemental scientific articles).
This second edition of the work adds significant amounts of new material to every chapter and virtually every topic covered in the text. Most importantly this new edition supplements the new text with many new figures and tables to both illustrate points made and to supplement the information provided on each topic covered.
The American Academy of Sleep Medicine (Ramar et al., 2021) recently put out an official position statement on the relation of sleep to all aspects of mental and physical health. It is the position of the American Academy of Sleep Medicine (AASM) that sleep is essential to health. I am in complete agreement with the AASM statement and will be presenting some evidence in this book which broadly supports the AASM position on sleep and health. Although it is now abundantly clear that sleep is essential to health for both adults and children, the AASM position statement notes that data from surveys conducted by the Centers for Disease Control and Prevention (CDC) and the Maternal and Child Health Bureau (MCHB) show that 34.1% of children, 74.6% of high school students, and 32.5% of adults fail to get a sufficient duration of sleep on a regular basis. In addition, the people who should alert the public to the need for better sleep are not getting the instruction on sleep they need to help the patients they serve. For example, according to the AASM position statement a multination survey of medical schools found that the average amount of time spent on sleep education is just under 2.5 hours, with 27% responding that their medical school provides no sleep education at all. Similarly, a survey of pediatric residency program directors in 10 countries found that the average amount of time spent on sleep education is 4.4 hours, with 23% responding that their program provides no sleep education at all. In addition, there is no formal training or certification in sleep medicine specifically for nurses, physician assistants, i.e. frontline health personnel. Only 6% of clinical psychology programs offer formal didactic courses in sleep medicine, with only 31% of programs offering training in the treatment of sleep disorders. Furthermore, actively practicing clinical psychologists in the U.S. and Canada reported a median of 10.0 hours of didactic sleep training across their training or career, and 95% of respondents reported no clinical sleep training at all.
In short, there is a clear and significant need for greater dissemination efforts of the latest findings on sleep and its relation to health at all levels of society but particularly in higher education, and in clinical practice. I hope that this second edition of my introduction to the neuroscience of sleep and dreams will contribute to that overall effort to provide greater resources to promote sleep education. One shortcoming of the AASM position statement on sleep and health is that they do not mention the role of dreams in health. We will see that dreams in fact are absolutely crucial for mental health and may also play a significant role in physical health. In addition therefore, to presentation of sleep neuroscience, I will present in this book some of the emerging research on the role of dreams and dreaming in the maintenance and promotion of mental and physical health.
Some of the questions I will be addressing include: What is sleep and why are there two basic forms of sleep (REM and NREM; at least among terrestrial mammals)? Why is the amygdala activated and the dorsal-prefrontal cortex downregulated during REM? What is the evidence for immune system repair during slow wave sleep? What is sleep debt and how is it related to brain function? What are the psychological consequences of chronic sleep debt? What do the major parasomnias teach us about conscious states? The many intriguing and bizarre clinical symptoms of various sleep disorders (sleepwalking, REM Behavior Disorder, Narcolepsy, parasomnias, etc) will be discussed as well as the latest findings on the role of sleep and dreams in memory, learning and mental health. With respect to dreams some of the questions to be addressed are: Why do some people recall very few dreams while others are flooded with dream memories on a daily basis? Why are social interactions so ubiquitous in dreams? Can certain dream experiences signal illness or even death? Why are some dreams extraordinarily moving and others quite banal and forgetful? Why do some people find it easy to realize they are dreaming when they are in fact dreaming (“lucid dreams”) while others never achieve “lucidity”? Do we need to dream in order to remember things? Do we need dreams in order to be creative? How is the new rage for using smart phones and apps to track sleep patterns and dreams altering our understanding of sleep and dreams? What about nightmares? Why do they occur and is there anything we can do about them? These are only a few of the fascinating puzzles concerning sleep and dreams that will be addressed in this book.
Unlike other introductory texts on sleep and dreams I adopt a consistently evolutionary and social neuroscience approach to understanding the neuro-psychology of sleep and dreams. I adopt this orientation as functional aspects of physiological systems are more easily understood within the framework of Darwinian evolutionary biology. To study sleep within an evolutionary context inevitably leads us to consider sleep as a social behavior, given that for most animals fitness trade-offs occur within social interactions. I will therefore argue that sleep can be profitably studied and understood, at least in part, as a social phenomenon. For example, fetal and infant sleep cannot be understood in the absence of its social context; that is, the infant’s interactions with its mother. Similarly, sleep states from toddlerhood up to adulthood also occur within social contexts (e.g., attachment relationships with parents in childhood and then attachment relationships with sexual partners in adulthood etc) that shape all aspects of sleep expression. Sleep expression differs in the solitary sleeper as compared to co-sleepers. Co-sleeping is very likely the evolutionary default for human beings. Our ancestors were all co-sleepers and that fact can help to explain some of sleep’s peculiar biologic features. While these elementary facts concerning sleep and social context have been assumed and occasionally acknowledged by sleep scientists, they have never received the sustained or explicit attention they deserve it seems to me. Placing sleep within its social context will assist readers of this introductory text on the neuropsychology of sleep and dreams by illuminating the everyday functional aspects of sleep and its disorders.
One final note for this preface. This second edition of the text was written during the COVID pandemic of 2020-2022. After reviewing existing studies on effects of lockdowns on sleep and dreams it became clear that the argument we made in the first edition of this book, that of the social nature of sleep (and dreams), was abundantly confirmed. The isolation and loneliness of many individuals during the COVID-related lockdowns significantly predicted altered sleep architecture, risk for nightmares and unpleasant dream content. These sleep and dream outcomes in turn could both exacerbate COVID’s effects on the individual or mitigate those effects depending on individual differences and circumstances. Kahawage et al (2022) content analyzed responses of 997 people from all over the world to a survey about COVID and the subjective experience of social disruption due to social distancing/lockdown policies. In describing their subjective experiences around daily and nightly routines during social distancing procedures people tended to report 4 major themes 1) loss of daily timed activities, 2) role of social interaction, 3) altered time perception and 4) disruption to motivation and associated psychological effects. The overall sense most people reported feeling was being psychologically ‘adrift' in time where sleep, dreams and waking activities tended to blend in together. Participants described feeling disoriented in both time and place, where days blended into one another and many reported that there was a sense of meaningless. Paradoxically lockdown and social distancing mandates made people both socially isolated AND sometimes trapped people into daily contact with housemates that they were not normally in daily contact with. The intensity of social contact in such cases tended to be a challenge, especially when the sleep-wake schedules of the other members were irregular and unpredictable. Inter-relations among the 4 major themes were organized into a provisional heuristic map (see Figure 2 in the book). Once social distancing procedures were in place psychological drift tended to emerge and then people had to choose how to handle that sense of drift. Successful responses to that drift often involved setting up regular exercise and sleep-wake routines and schedules. Failure to do so resulted in poorer outcomes and chronic distress.
Studies on the ways in which the dreaming brain responded to the pandemic, including the threat of illness and the associated social distancing policies, in many ways revealed the power of dreams. To take just one example , Šćepanović et al., (2022) utilized a deep-learning algorithm that extracted mentions of medical conditions from text and applied it to two datasets collected during the pandemic: 2888 dream reports (dreaming life experiences), and 57 million tweets (waking life experiences) mentioning the pandemic. Analyses of these datasets revealed that health expressions common to both sets were phrases concerned with, or depicting typical COVID-19 symptoms (e.g. cough, fever and anxiety). Expressions in waking life, however, described symptoms in realistic or common-sensical ways (e.g. nasal pain, SARS, H1N1); while those from dreams appeared to be more metaphorical and uncommon (e.g. maggots, deformities, snake bites), or conditions of surreal nature (e.g. teeth falling out, body crumbling into sand). In the figure depicting these findings note that the dreams (blue nodes) produce accounts of the COVID experience that appear to be exploring the outer edges or difficult to define, margins of the experience. This kind of information is invaluable to people either infected with the virus (to help prepare for what may come), for those helping ill patients and for the rest of us who are just trying to cope as best we can with the daily challenges of a pandemic. In ordinary people, therefore, dreams both predicted and captured/described a larger part of the COVID experience than discursive waking reflections on the experience. No account of sleep, then will be adequate without an account of dreams. There is no neuroscience of sleep. There is only a neuroscience of sleep and dreams.
