Hearing voices or having auditory verbal hallucinations and delusions is emblematic of psychosis. There is a sense in which both concepts are part of the infrastructure for modern psychiatry. Given the importance of hearing voices as a canonical concept in psychiatry, it is surprising that it has received little focused attention in its own right. In this book McCarthy-Jones has changed that. He has written a comprehensive, indeed encyclopedic text. His aim is to focus on four key areas: the varying history of hearing voices, its phenomenology, causes, and meaning.

The history draws on material from ancient Mesopotamia through to our own times. This exercise is not a perfunctory gesture but a reasoned and well-argued case for examining the diachronics of the experience and meaning of hearing voices over time, as a means of exploring and investigating the continuities and discontinuities of the phenomenon, of the tentative causal explanations, and of the attributed symbolic understandings. For example, McCarthy-Jones explores Julian Jaynes’ theory that all humans automatically heard voices in the period 9000–1000 BC as a result of possessing a bicameral mind. This broke down in around 1400 BC, and humans developed self-consciousness and inner speech. The author concludes that there is little evidence in support of this theory and in any case the detailed evidence that Jaynes put forward, drawing on the Illiad and on Mesopotamian poetry, on careful analysis does not provide proof for his contention.

McCarthy-Jones is at his best when he critically reviews the scientific evidence for the frequency of auditory verbal hallucinations in psychosis, in post-traumatic stress disorder, in borderline personality disorder and in other conditions such as Parkinson's disease. In his interrogation of the various causal hypotheses, he deals with inner speech theories and concludes that evidence from a number of sources, including studies of amplified whisperings, functional and structural neuroimaging, all suggest a role for inner speech in verbal hallucinations. There is an obvious mastery of the subject matter and he is sure-footed in guiding the reader through a complex and often contradictory literature.

He is less focused and incisive when he deals with the social and symbolic meanings of verbal hallucinations. There is a tendency to want to normalise the experience of hearing voices. The fact that normal people (that is, people who are not seeking psychiatric attention and who are not distressed by their experience) ‘hear voices’ is not evidence that ‘hearing voices’ is not a sign of psychopathology. It is helpful, perhaps, to remember that normal people have tachycardia but tachycardia is also a sign of cardiac pathology. Normal people can be very tall but being very tall can itself be a sign of pituitary pathology. This simple fact that a phenomenon can be both a sign of pathology as well as innocuous is often misunderstood.

There is a risk that McCarthy-Jones’ approach may suggest that auditory verbal hallucinations are somehow discrete entities. It is, of course, reasonable to deal with verbal hallucinations for academic purposes as a distinct class of experience. However, unlike delusions where patients can present with discrete delusional disorders in the absence of any other psychopathology, as in persistent delusional disorder, discrete verbal hallucinatory disorders in the absence of other psychopathology are rare. Furthermore, verbal hallucinations are on a continuum from thoughts heard aloud/thought echo to thought broadcasting (where the patient believes everyone can hear his thought because he can hear it himself), through to one-word elementary verbal hallucinations, to whole-sentence complex verbal hallucinations. And there are commonalities between all auditory hallucinations whether elementary noises or music and across all modalities of hallucinations that ought to be drawn out.

This book will bear re-reading. It is equally accessible to the specialist as to the generalist. There is a wealth of information, a keen examination of theory, a critical disposition, and above all it is interesting and engaging.