The babies had been switched, of that she was sure. Would her own baby smell like this — like rot? Impostor. She guarded the truth quietly: Her real baby actually lay beneath a small, tilted headstone, in the graveyard near her home. The patient was a woman with no history of psychiatric illness. After giving birth, she went mute, stopped eating and ignored the infant. By the time she was admitted into treatment, she was suffering from full-blown postpartum psychosis. Veronica O’Keane, the Irish psychiatrist who treated this woman, recounts her story at the beginning of “A Sense of Self,” her new book about the science and mystery of memory. Edith, as O’Keane calls her patient, quickly recovered with medication. She understood that her psychosis was precipitated by the storm of birth hormones, and was ecstatic to be reunited with her baby. But passing the graveyard months later, she saw the small, tilted headstone and her memories returned in a rush of terror — along with the belief that her baby had been switched. She was able to accept that her thoughts were not true, but she told O’Keane: “The memories are real.” “What she said,” O’Keane writes, “set me on a long-term pathway of inquiry about the nature of the matter of memory.” This book was originally published in Britain under the far superior title of “The Rag and Bone Shop,” with its homage to the Yeats poem “The Circus Animals’ Desertion” (“I must lie down where all the ladders start / In the foul rag and bone shop of the heart”) and its hint to the author’s approach. O’Keane builds her investigations upon case studies and new research along with deep readings of Proust, Beckett, Sandor Marai and Alice Munro. When I praise her talent for metaphor (the hippocampus is “the marionettist”; the amygdala, our “emotional sparkplug”) it’s not just for its literary effect. O’Keane’s preoccupation is with sensation: How does sensory input translate into information, blossom into knowledge and experience, become preserved as memory? “The fundamental point that we cannot make memories without sensation may be so familiar to us that we are blind to it,” she writes, but “the shift in the understanding of memory from being a static repository of knowledge to being a dynamic living human experience is a profound one, and was highly contested.” Editors’ Picks Speaking Truth to Both the Right and the Left Farewell, Millennial Lifestyle Subsidy Why ‘Unwell Women’ Have Gone Misdiagnosed for Centuries Continue reading the main story Hence the necessity for metaphor, for pungent, highly precise language: to jolt the reader into feeling herself. For it’s from feeling that the book proceeds — from the testimonies of patients, their convictions and terrors, into the “neural memory lattices.” O’Keane’s account seeks to dethrone theory, taking as its credo a line from Beckett: “I am not an intellectual. All I am is feeling.” On occasion, this method can prove a little too smooth; notions of consciousness are more contentious than they are sometimes presented here in a deracinated form. O’Keane’s attention is trained on her patients’ experiences, not their symptoms, and not on philosophical debates over personhood. For her focus, there is yet something peculiar, and oddly admirable, about how unsatisfying many of these case studies remain. Even Edith, who sparks the book, scarcely emerges as a character in her own right. As for the rest — shadow puppets. This is not for lack of narrative skill; in one section, O’Keane evokes a robin in her backyard with a vividness that would shame a good many novelists I’ve encountered this year. It’s an instinct for privacy that prevails, one feels. She will share stories from her practice, but she is reluctant to feed a voyeuristic impulse, reluctant to entertain. Her patients do not perform on the page. Today’s therapist or physician-narrator so often follows in the footsteps of the gentleman detective — laconic, impersonal, invariably heroic. Along comes O’Keane, so interestingly cagey at times. She often writes about patients she could not help or ones she stopped hearing from, those for whom she could offer only witness. She writes in one case about her sense of helplessness: “I felt that I was simply an observer of some catastrophic brain event.” As a clinician, she is haunted, full of doubt and regret — leagues away from the twinkling omniscience of an Oliver Sacks. O’Keane does not try to dazzle us with interpretations and cures, but dazzle she does with the science, the clarity with which she can conjure something as ordinary, as bafflingly complex and beautiful, as a memory forming in the brain. She leads us through the origin of sight, why looking always involves remembering, the importance of place in memory, what starlings can tell us about sex, about scientists who believe it may be possible to reactivate happy memories through stimulation of the amygdala. Out of that unprepossessing organ — “a gelatinous blob of uncooked-shrimp color” — what wonders. O’Keane draws on her own life with customary tact. She recalls the Irish folklore of her childhood (she connects it to Edith — she sees the stories of the changelings as a form of intergenerational wisdom, a way of warning women of the strangeness that follows a birth). She describes her time working in one of the last remaining asylums in Dublin — a setting more complex than commonly portrayed; at their most functional, asylums provided patients with a kind of protective village. She writes of her own mind and its terrors. O’Keane long worried about encroaching cognitive staleness. She quotes Marai: “Gradually we understand the world and then we die.” To her surprise, the richness of the natural world keeps imposing itself — recall that vivid little robin. “One returns to the world of sensation,” she writes, with wonder. “Not the headlong hurtle of youth, but a richly nuanced one that you want nothing from, except to be in it.”