The Science of Sleep

Reviewed by Elina Thomas, Assistant Professor, Earlham College on 7/23/25

Comprehensiveness rating: 4 see less

The text is relatively comprehensive. It covers how the brain is involved in sleep in a simplified but helpful manner and does an excellent job discussing various factors that contribute to sleep quality. Information regarding sleep stages, sleep architecture, and circadian rhythm is particularly thorough. The text builds upon itself well, and topics introduced later require the reader to remember what they have learned earlier in the text (e.g., the EEG reading of ground squirrels during hibernation). There is a large focus on ways to improve and examine one’s sleep practices, which makes the text easy to engage with. The contents section, which precedes the start of the book, is helpful and describes the topics covered in the text quite well; however, there is no index or glossary provided outside of this, which would allow the reader to find key terms in the text. The book does an excellent job of providing sources for images in the text, giving credit to their origins. It would be helpful for section headings to be more informative so the reader is more aware of what the upcoming section will cover.

Content Accuracy rating: 4

The information presented is mostly accurate; however, providing more background information would be helpful before discussing certain concepts (e.g., the definition of a neurotransmitter should be supplied before discussing particular neurotransmitters). Certain concepts could benefit from a figure (E.g., when neurocircuitry is discussed, a diagram would aid the reader in understanding how GABA circuitry functions as a “double-negative”). The reader may need to consult additional sources to gain a thorough understanding of the text. Some information is inaccurate (e.g., a relationship between Bipolar Disorder and sleep paralysis has not been established; however, some literature suggests the same neural circuits are dysregulated in both). Providing citations for primary or secondary literature to support claims like this throughout the text would be helpful. Outside of these minor examples, key concepts described in the text appear to be accurate.

Relevance/Longevity rating: 4

Generally speaking, the context is up to date and unlikely to become obsolete any time soon. Updates should be fairly easy to implement. The text would benefit from the inclusion of newer methodologies involved in the study of sleep (e.g., fMRI); this could be easily integrated into the brain section through descriptions of how scientists discovered what regions are involved in sleep. In describing the lobes of the brain, it would also be helpful to add the subcortex as a key brain section before introducing structures like the insula and amygdala.

Clarity rating: 4

The text is written very clearly and should be easily accessible to most audiences. However, at times, adequate context is not provided for the technical terminology that is used. Content encourages a critical understanding of study results, and activities like orienting readers to “correlation vs. causation” encourage critical thinking and a greater understanding of how to interrogate primary articles.

Consistency rating: 5

Key terminology is consistent throughout the text. Additionally, the text integrates terms into future examples well (e.g., squirrel hibernation and EEG waves), which helps the reader engage with the content more critically.

Modularity rating: 5

The text has been divided into sections that would be easy to assign for class readings, though it is a bit self-referential with statements like “One of my mentors in social justice and anti-racism told me…” and “one of my passions is…”.

Organization/Structure/Flow rating: 5

The text is well organized; however, some information presented requires background knowledge (e.g., decreased heart rate variability is mentioned early on as a consequence of sleep deprivation). Another example can be found in the “Nighttime Urination section,” where a large diagram of the male reproductive system is presented, with many labels; however, the prostate gland is the only region mentioned in the text. It would be helpful for section headings to describe the general conclusion of the section, E.g., the section “Light” could be changed to something like “Light impacts circadian rhythm and sleep quality.”

Interface rating: 4

The text interface is well presented. Student learning objectives give the reader a comprehensive list of what they should take away from each section. The inclusion of an index at the end of the book, including key terms and their locations in the text, would be helpful.

Grammatical Errors rating: 5

No grammatical errors appear to exist in the text.

Cultural Relevance rating: 5

The text is exceptionally culturally inclusive. A multicultural perspective is implemented throughout the book and exemplified in discussions throughout (E.g., a biological rationale for the “siesta”). The “Guide to the Textbook” used throughout the book is based on concepts from various cultures, which are discussed before the introduction. Perspectives from different cultures are offered throughout the text (e.g., the use of dreams in Ancient Egypt). Multiple factors that contribute to associations between sleep, quality of life, SES, education, race/ethnicity, and social justice (e.g., “The sleep wellness gap” and impacts of discrimination) are also discussed and integrated well.

Comments

This is an enjoyable read that comprehensively covers sleep at an introductory level. There are a few minor issues that do not detract from its usability for a course. As is, it would be an excellent book to assign for an introductory course on sleep. When mentioning specific research studies in the text, it would be helpful to cite primary or secondary literature for the reader to reference. This is something the instructor will likely need to find and supplement throughout the course.

Reviewed by Christopher Vecsey, Professor, Skidmore College on 6/17/25

Comprehensiveness rating: 3 see less

This textbook’s level would be most appropriate for undergraduate college students, though would be accessible to high-school students as well. It covers many key areas of sleep, with an overall focus on human sleep (with almost all mention of sleep patterns in other animals consolidated into Chapter 4). This textbook does not delve too deeply into genetic, cellular, or molecular mechanisms of sleep, though entry-level descriptions of sleep-regulating brain regions and neurotransmitters, etc., are provided. The incorporation of substantial material about social justice issues related to sleep is a major advantage over most other books about sleep, including textbooks and books aimed at the general public.

Content Accuracy rating: 4

Content is accurate and provides unbiased coverage of sleep issues. Some references are provided, but the textbook could be improved by strengthening the references section, as it is difficult to determine the sources for a fair amount of the content.

Relevance/Longevity rating: 4

Content is currently up-to-date and useful, but the scientific study of sleep is a relatively young field that continues to grow and develop. Thus, there will likely be some updates needed every few years. However, because many of the new advances relate to the genetic, cellular, and molecular levels, which this textbook does not focus on, updates may not be needed very often.

Clarity rating: 5

I found the writing to be extremely clear and accessible, even for an audience without much background in neuroscience or biology in general. Complicated terms are all explained clearly, and the style feels quite conversational as opposed to a stuffy, dense textbook format.

Consistency rating: 5

The textbook builds consistently off of previously introduced concepts.

Modularity rating: 5

I found each chapter to be divided up into very manageable sub-sections. Some chapters do depend on previous information (in particular, Chapter 2 about Neuroanatomy, etc.), but this is to be expected. In most cases, individual chapters could be assigned separately. Chapter 7 about the Politics of Sleep could be used separately from the rest of the text, e.g.

Organization/Structure/Flow rating: 4

Overall, the topics are presented in a logical, clear fashion. I only have two suggestions. The first is that I wish that research findings, especially those from non-human animals, were incorporated into multiple chapters to make it clear where much of our understanding of sleep has come from. The second is that Chapter 1 about Sleep Wellness might fit better coming at some point after Chapter 2, since some of the content, e.g., about nicotine effects on sleep, might make more sense once the neurotransmitters involved in sleep regulation had been introduced. But otherwise, the organizational flow makes a lot of sense.

Interface rating: 4

I evaluated the downloaded PDF version, and found it quite easy to navigate the textbook, and the images and charts were all easily legible. I only wished that some of the complex figures had more substantive figure captions.

Grammatical Errors rating: 5

The text is well-written and I did not notice any grammatical errors.

Cultural Relevance rating: 5

This is a major strength of this textbook! It repeatedly incorporates Hawaiian culture and vocabulary, and the chosen images are extremely diverse, showing people of many ethnicities and cultures, but also athletes with disabilities, etc. Another strength of this textbook is its focus on social justice as it relates to sleep health. This topic has historically been largely ignored, but it is coming into focus, and the author rightly dedicates an entire chapter to this. In addition to simply covering material about why people from disadvantaged backgrounds tend to have worse sleep outcomes, the author also includes sections suggesting ways that the reader can take action and engage with their community. I love this, as it makes the important point that as a person learns information about issues in a textbook, they now have the power to act on that information, by either educating others or working to fix the underlying issues.

Comments

I am planning on teaching a course that would be accessible to all undergraduate students, not just science majors, about social justice issues as they relate to sleep and circadian rhythms, and this textbook will be a very useful resource! It is freely accessible, introduces basic neuroscience concepts at an appropriate level, emphasizes the social justice implications associated with sleep health, and consistently suggests action items through which readers can make an impact.

On the other hand, based on the conscious choices the author has made to focus more on introductory concepts related to human sleep health and less on the underlying mechanisms, this textbook would not be as appropriate for upper-level or neurobiology-focused courses on sleep.

Reviewed by Kristen Genet, Unlimited Full Time Faculty in Biology, Anoka-Ramsey Community College on 1/29/24

Comprehensiveness rating: 3 see less

The book comprehensively introduces the biology, psychology, and cultural context of sleep, but it does not include reference material at the end such as an index (although there is a table of contents at the beginning) or a glossary. Throughout, references are provided as footnotes, but I think students and faculty alike would benefit from more thorough listing of references as well as the index/glossary.

Content Accuracy rating: 4

The material presented is clear, objective, and supported by references from scientific literature.

Relevance/Longevity rating: 4

Up to date when published, but references to "new" research will benefit from updates, especially for the topics that represent new developments as of the publication dates.

Clarity rating: 5

The book is written clearly and logically. The technical parts are explained in simplified terms, figures are provided, as well as references for more information.

Consistency rating: 5

Terms and concepts are introduced and then referenced in multiple chapters. This helps to reinforce the concepts and repetition makes the meanings and connections clearer.

Modularity rating: 4

The text is broken into logical and manageable sections that could be assigned/considered as individual modules. Some sections are much longer and more complex than others, however.

Organization/Structure/Flow rating: 5

The topics are presented in a logical and clear order.

Interface rating: 4

I evaluated the PDF version, and also looked over the MS Word version. The PDF version would be best viewed either as whole page or printed, so the placement of figures and the formatting of the columns does not require scrolling back and forth to read and interpret things that don't fit together on one screen. Images were not included in the MS Word downloaded version and formatting was not reader-friendly, so I would not suggest that version. An interface that would allow continued flow of text with thumbnails of figures that could be expanded so they're visible at the same time as reading the relevant text would be better, and that's one of the benefits of other online texts that I have used.

Grammatical Errors rating: 5

Well written and edited.

Cultural Relevance rating: 5

The cultural context and social justice component was one of the best features of this book. Clearly this book was written from the Hawaiian perspective, and predominantly for an audience of Hawaiian students, but the references to indigenous culture and the integration of social justice issues and action items woven throughout the text were powerful ways to include diversity and culture into the text.

Comments

I am teaching a seminar course on the biology of sleep, and I think this book (at least sections from it) will be a great resource to provide to students for many of the topics we will be discussing.