This book begins with a discussion of atypical readers and the impact had on their lives by a spectrum of neurological conditions affecting their ability to make sense of the printed word. The first history of neurodivergent reading, it relies on personal testimonies that have largely been left out of conventional histories of reading to express how cognitive differences shape people's experiences both on and off the page. The book's introduction identifies the neurological conditions most relevant to reading: dyslexia, hyperlexia, alexia, synesthesia, hallucinations, and dementia. It proceeds to explain how the book's focus on neurodiversity aims to transform our understanding of the very concept of reading. In place of "the ideal reader" envisioned by reader-response criticism and other theoretical schools, it calls for room to be made for "the unideal reader" whose disabilities make reading difficult or even intolerable.

Chapter 1 addresses the best-known set of reading differences: dyslexia, the term used by the medical profession to describe difficulties with word recognition and decoding skills that interfere with an individual's ability to read fluently. This chapter directs attention to the dyslexia memoir, whose authors give first-person accounts of the impact of reading differences on everything from their personal lives to the perception of print. The experiences of dyslexic readers upend one of the most fundamental assumptions about how humans apprehend books: typographical fixity, the expectation that a page of text will remain identical from one viewer to the next. By contrast, dyslexic readers confront what might be called typographical fluidity: a page whose appearance changes from one reader to the next or even from one reading to the next.

This chapter on the neglected history of autistic reading practices looks at readers who appreciate aspects of textuality that tend to go unnoticed by other readers. Some children on the autism spectrum exhibit a precocious ability to read and remember entire books without seeming to understand a word of them—a condition known as hyperlexia. Such experiences challenge the conventional understanding of reading as an interpretive activity. Instead of reading to understand a text's meaning, as most people do, many readers on the spectrum prefer what this chapter calls surface reading: a preoccupation with a book's surfaces, from the shapes of its words to the textures of its cover, binding, ink, paper, typefaces, and so forth. If theories of reading generally focus on hermeneutics, or methods of interpreting texts, then this style of reading stands out for its refusal to delve beneath the surface.

Alexia is a neurological syndrome in which a literate adult loses the ability to read. This chapter examines over a century's worth of medical case studies and other narratives documenting the impact these reading deficits have had on people's lives, well-being, and sense of identity in societies that stigmatize the inability to read. The complex responses to what this chapter calls postliteracy bring into view the mechanics of a process to which most people pay little attention after learning to do it as children. Postliteracy narratives expose what may feel like a smooth, automatic process to consist of multiple neurological operations that at any moment can go awry, forcing a reckoning not only with what it means to read but also with what it means to be a reader.

This chapter explores the relevance of synesthesia to literary criticism by asking: What effect might perceiving the alphabet in luminous colors have on the experience of reading? Synesthesia is a neuropsychological condition that causes the stimulation of one sense to evoke a sensation in another sense. One of the most common forms involves the perception of color in response to printed letters; for example, the black letter "A" might be perceived in the reader's mind as a red "A." Whereas literary critics have traced the use of cross-sensory metaphors for artistic ends, the testimonies of actual synesthetes have received surprisingly little attention. Drawing on personal testimonies of what it feels like to read in color, this chapter traces how the mental imagery and other sensory effects perceived by synesthetic readers influence their responses to books.

This chapter examines how hallucinations affect people's encounters with books. It is widely believed that books supply a shared framework enabling audiences to judge the validity of various interpretations of them. But this pretense of consensual understanding is undermined by readers who visualize letters, words, sentences, books, and even other readers that no one else can perceive—what this chapter calls seeing "things." Those who are prone to hallucinating can never know for certain whether they are viewing the same page as other people—or even a page at all. Testimonies gathered from various sources, ranging from the Bible to memoirs written by patients with firsthand experience of psychosis, illustrate the many ways hallucinations can disrupt efforts to read.

This chapter examines how memory loss affects people's ability to engage with texts. Dementia and neurogenerative diseases make it difficult to concentrate on books or even to remember what's in them. Drawing on the dementia memoir as well as original analyses of classic narratives adapted for audiences experiencing memory loss, this chapter demonstrates how testimonies about living with dementia single out aspects of the reading process that have been undervalued by a literary discourse invested in plot and the retrospective comprehension of narrative. Instead, these accounts celebrate methods of engaging with narratives whose value does not depend on completion. Such testimonies undercut the widespread supposition that memory is a necessary component of reading. Contrary to expectations, many people with dementia continue to derive pleasure from books long after they have ceased being able to read them in the familiar sense of the term.

This epilogue identifies the benefits for literary critics, book historians, cognitive humanists, and the general reader of moving toward an inclusive understanding of the term "reading." The examples of neurodivergent readers cited throughout this book call for an expansive definition of reading that would extend to the diverse ways people interact with texts. Thinking about reading in terms of a spectrum capable of accommodating the full range of behaviors documented throughout this book can therefore lead to a richer understanding of what it means to read.