As progress shapes views of the institution, disintegration and degeneration invisibly shape thinking about the illness. Although psychiatrists emphasize to the public that schizophrenia is not "split personality," in informal (unprofessional) conversation, staff often refer to patients as cracking up, falling apart, or going to pieces. An acute psychotic episode is called a break, and the design of psychiatric book covers and pharmaceutical advertisements often feature split or fractured images. Psychodynamic concepts represent this as the dissolution of ego boundaries and personality accompanied by a unmodulated emergence of primitive and incomprehensible experience. Biologists express this idea in terms of neural circuits released from inhibitory control, perhaps by an unmodulated excess of neurotransmitters. Barrett the psychiatrist competently reviews the history of these formulations, but Barrett the anthropologist is concerned not with their scientific merit but, rather, the cultural meanings they carry. He argues persuasively that different theoretical perspectives reflect common, deeply embedded conceptions expressed in different idioms. Clinicians, scientists, patients, and the public alike are influenced by these cultural images and metaphors.