In the preface, Emmorey states her goal for this book: to illustrate what can be learned about human language, cognition, and the brain by studying signed languages and the deaf people who use them. She clearly achieves that goal in this excellent volume. Her scholarship is impeccable, something we have come to expect from this author. First of all, the organization of the book is impressive. Each chapter explicitly presents specific goals and then proceeds through those goals in an organized and clear style. The conclusion of each chapter includes suggested readings with a brief explanation of how these suggestions support the chapter. Second, this volume includes research on a variety of signed languages—Nicaraguan, Australian, Danish, and Irish, to name a few—and provides a truly comprehensive approach to the topic.

There are nine chapters that address language, cognition, and the brain. The early chapters primarily focus on language. Chapter 1, “Introduction,” lays waste to four misconceptions about sign language and sets the record straight: There is no one universal sign language; sign languages, although gestural, are much more intricate and complex than mime; sign languages developed independently and did not have their beginnings in spoken languages; sign languages can convey concepts that are just as complex and subtle as those conveyed in spoken languages. Then, there is a reporting of the origin of Nicaraguan Sign Language—the foundation for the following chapters—because this discussion contains all the pieces that will be expanded in each subsequent chapter. It is important to note that Emmorey's work focuses not only on a discussion of language but also on the people who use the language—truly a sociolinguistic approach.

Chapter 2, “The Structure of American Sign Language: Linguistic Universals and Modality Effects,” presents what we currently know about the structure of American Sign Language (ASL) and explains why and how studying this structure informs us about human languages in general. Chapter 3, “Confluence of Language and Space,” presents a clear, concise, and comprehensive explanation of space in ASL. In particular, Emmorey's explanation of ASL classifiers is luminous, from her review of what we already know about the topic to the deceptively simple question, “Why are they called classifiers?” This particular ASL construction is quite complex and is often presented to ASL learners (i.e., speakers of English) with an incomplete explanation. Chapter 4, “Psycholinguistic Studies of Sign Perception, Outline Processing, and Production,” explores which parts of language processing are affected by modality (visual vs. aural, gestural vs. articulation) and which parts are universal. Both chapters 5 and 6, “Sign Language Acquisition” and “The Critical Period Hypothesis and the Effects of Late Language Acquisition,” are excellent. They fit well into the structure of this volume, but they could also stand alone as resources for those involved in educating deaf students, as well as for second language teachers (of any language). Emmorey's clarity of the sign acquisition process in deaf children is outstanding.

Now that sign language has been comprehensively presented, chapter 7, “Memory for Sign Language: Implications for the Structure of Working Memory,” and chapter 8, “The Impact of Sign Language Use on Visuospatial Cognition,” shift toward Emmorey's primary discussion of cognition. Chapter 9, “Sign Language and the Brain,” questions “whether the contrasting sensorimotor properties of sign and speech constrain the underlying neural systems for language” (p. 271). There is also an epilogue in which Emmorey reminds us that this volume is a beginning: “there is currently an explosion of studies” (p. 318) on a variety of signed languages and the brain. I am hopeful that Emmorey's work serves as a model for those involved in the explosion.

This book would be of interest to anyone who wants to understand more about human languages and how the brain processes those languages, although knowledge of ASL and linguistics (especially phonology and morphology) would be helpful. As a second language learner and educator who has spent over 25 years challenged by the nuances and intricacies of ASL, I can honestly say I was fascinated with this book. Some parts were a succinct review of what we already know, some parts presented cutting-edge information, and some parts were quite challenging. Ultimately, however, the book made me think about what I already know and encouraged me to continue exploring how the brain processes language.