There have been several studies touching on medieval mental health over the last hundred years, approaching the subject, as Turner signals in her introduction, from a range of angles: medical, legal, literary, or ecclesiastical history. Medieval disability studies have been flourishing in the last ten years, and Turner makes reference to the research of Irina Metzler, which has greatly enriched our understanding in this area. With Care and Custody of the Mentally Ill, Incompetent, and Disabled in Medieval England, Turner moves to fill a gap in our knowledge about the medieval social understanding of the "mentally incapacitated," as well as the care and custody of the "mentally disabled." With this study, Turner brings many case studies to our attention, creating scholarship that is supported by exhaustive archival research.
"Mental illness," as Turner points out in the introduction, is modern terminology. Thus, she takes care to delineate the terms that she applies to her medieval subjects. For instance, she explains a difference between the mentally "disabled," "ill," and "incompetent," and between "mental afflictions" and "physical disabilities" (5). There is, nevertheless--and understandably--some confusion in arriving at clear language in this book. For instance, despite the fact that Turner elects to use "medieval terminology with modern explanations of what these terms meant," she employs certain terms that are neither medieval, nor widely considered appropriate today, such as "mental or physical handicaps" (221). In other places, it is unclear if the phrases used are medieval ones, or objectionable modern terminology (for example "mentally feeble"/"feeble-minded," used throughout the book); in the introduction Turner implies that these are terms she has chosen to encapsulate several medieval ideas (7). Recent studies have questioned the notion that the term "mental illness" is appropriate at all.  Though it is still widely-used, certain psychiatrists call for abandoning the term as a straightforward distinction from neurological conditions. Turner is keen to avoid "presentism"--rightly so--but a more nuanced recognition of the inherent complexities, and remaining controversies, concerning the persistent and controversial dualism of body and mind in the term "mental" illness/disability/incompetence would have enhanced the introduction. 
Chapter 1 explains the classical underpinnings of medieval concepts about mental incapacitation. It looks at biblical ideas that mental affliction was either a form of punishment from God or the result of being tormented by demons. Following this, Chapter 2 expounds the legal status of the mentally incapacitated in twelfth and thirteenth-century England. This centres upon a distinction between people born without mental capacity and those who became mentally incapacitated, and those who did or did not have lucid intervals. The chapter considers a range of medieval legal commentaries and their relationship with Roman law. The chapter moves through several texts (for example Bracton, the Prerogativa regis, Britton, Fleta, and The Mirror of Justices) and their explanations of legal categories, property rules, and guardianship procedures pertaining to the mentally incapacitated. Turner goes to considerable lengths to discuss the meanings of the categories, and a helpful glossary in Appendix 1 is amongst the apparatus of the book.
Chapter 3, on "Determining Insanity," provides a much-needed overview of the medieval medical understanding of various conditions. The explanation of the regions of the brain and their perceived relationship with the functions and senses is clear, and well-supported by reference to medieval medical writers. Turner’s explanations of medieval neurological understanding and humoral theory, and the often physical remedies for head-related illnesses, makes a pertinent connection between the physiological and the "mental" in medieval medicine--which might, in fact, have been useful in the introduction. A section on administrative terminology highlights a focus on behaviour and temperament rather than medical cause, which leads logically into sections on how self control, cognitive abilities, and memory were tested. This section is elucidated successfully using a series of case studies. Chapter 4 explores how officials investigated allegations of incompetence, beginning with the use of sheriffs by Henry III, through to the employment of specially-appointed commissioners and escheators by later medieval kings.
The issues of accountability and punishment for crimes are considered in Chapter 5. Turner presents the interesting issue of malingering: a mentally incapacitated person could be deemed accountable if they were acting, "under pretence of madness while enjoying lucid intervals" (112), and again the whole chapter is underscored by illustrative case studies. There are one or two throwaway comments, such as Turner’s assertion that children murdered by their neighbours, "did not have enough sense to stay out of the reach of mentally incapacitated persons who could not control their actions" (122), which seems unfairly conjectural and harsh. However, the central focus of the chapter, achieved effectively through examples, is to demonstrate a reluctance to punish people who could be shown to be incapacitated. Chapter 6 outlines a shift from family to crown-driven care when inheritance was contested. Turner emphasises the financial incentives for the crown’s involvement, as well as the benefits for the king’s local authority, as he appointed guardians who were sympathetic to royal interests.
The theme of the financial benefits of wardship for the crown is continued in Chapter 7. Despite the title of the book, it is more accurately a story of "property management," and wrongdoing, rather than "social care"--a limitation of the source material which Turner herself recognises. Chapter 8 turns to the practical role of the guardian in the life of their ward. We learn, through the highly-detailed case study of John Brewes, that some incapacitated persons had several guardians, each assigned different tasks in safeguarding the person’s property by the king’s officials. There is an overview of the income that the crown made from wardship, based on figures given in Exchequer records for sample years, and a study of the use of both family and non-family guardians. Finally, there is a consideration of how wards might be abused by their guardians; an intrinsic problem with the system of wardship for the mentally incompetent. The final chapter examines a shift in perception in the fifteenth century when, Turner argues, views of the mentally incapacitated became increasingly negative. It charts the decline in the use of wardship, the skipping of mentally incompetent heirs, and the shift of some care to hospitals taking in the mentally ill. However, in concluding the book, Turner makes the important assertion that there was never any universal culture of shame attached to mental incapacity in the Middle Ages, and most of the mentally incompetent were not pushed to the "fringe" of society.
In sum, from the title onwards, this book struggles with some inherent difficulties in terminology for mental health. Today, we continue to grapple with the words used to conceptualise and talk about health and disability; the language is under constant revision. With these shifting sands in mind, it is perhaps unsurprising that the books highlights difficulties in applying modern demarcations to medieval source material. Regardless, this work presents interpretations of newly-uncovered source material which will clearly succeed in, as Turner hopes, "beginning a dialogue about mental disability in the Middle Ages." The book’s strengths lie in presenting Turner’s work in the archives, resulting in a range of case studies relating to medieval mental health. The care that the author takes to explain her arguments means that the book can be repetitive. However, the case studies tell stories that both inform and breathe life into her assertions regarding the care and custody of the mentally incapacitated. So this work gives us a detailed analysis of hitherto under-studied source material, whilst uprooting controversies and stimulating debates that will continue long beyond its publication.
1. P. D. White, H. Rickards, and A. Z. J. Zeman, "Time to end the distinction between mental and neurological illnesses," BMJ 344 (2012): e3454.
2. In the interests of the fluidity of this review, I use Turner’s terminology here without inverted commas, whilst acknowledging that some might be contested.