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A neuroscientist recounts a career spent searching for insight into our psychic struggles

Projections: A Story of Human Emotions

Karl Deisseroth
Random House
256 pp.
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Karl Deisseroth’s Projections: A Story of Human Emotions is a memoir about his life in psychiatry, the patients he has met, and his efforts as a scientist to solve the mysteries of mental illness. His imaginative narrative flows effortlessly through his many passions. There is a first love of reading and writing and hints of a literary imagination that draws on James Joyce and Toni Morrison. And there is the light of optogenetics, a trick of nature pioneered in Deisseroth’s laboratory at Stanford University that makes brain cells responsive to photonic pulses.

Like many doctors, scientists, and caregivers before him, Deisseroth endeavors to find an emotive language for the psychiatric patients he meets. He accomplishes this by weaving together what he describes as three strands: psychiatric knowledge, technology, and imagination. These together free him to write poetically, seeking to discover loss and grief, fracture from reality, and disruptions that threaten selfhood. The patients who wander through Projections thus encapsulate a variety of heartbreaking tragedies and shocking breaks from reality. Along with individuals suffering from anorexia and bulimia, Deisseroth describes cases of profound depression, mania, autism, self-harm, stroke, dementia, and schizophrenia.

His narratives are always sensitive, but they come to the reader as an admixture of fact and fiction, reality and imagination, damage and desire. Deisseroth is, in essence, proposing that we must use our imaginations to understand those in psychiatric crisis.

At one point, he projects himself into the mind of one of the patients he encounters and subsequently diagnoses as experiencing psychosis. He asks us to think with her about a neighbor’s satellite dish that seemed “to download her thoughts.” A trick then occurred to her: “She dug out a heavy black knit cap…pulled it down tight over her ears…there was no doubt—the satellite signal felt less likely to get in, or her thoughts to leak out.” The reader at once comprehends the perceived threat posed by the satellite dish and the patient’s desire to preempt the mind reader’s damaging effects on her psyche. If an entity is trying to read our mind, shouldn’t we stop it? And shouldn’t we stop the psychiatrist who seeks to control us?

Our expectations of such control prove illusory in all ways. Deisseroth is disturbed to discover that people around him, a student in particular, have seemingly hidden mental disorders in plain sight. “What had I missed?” he whispers in the prose, just as we might ask ourselves were we placed in a similar situation. He ruminates on his own identity as a single father, leaving unsaid but obvious to his readers that the mysteries psychiatry confronts may strike any of us at any time and we may be more blameworthy than we know.

Against these imaginative strands, Deisseroth situates his optogenetics research as a technological source of illumination. Optogenetics helps us understand the way ancient anatomical pathways or deeper evolved drives can project into our behaviors. Each time, however, the pull of the science, and indeed what the science shows, only takes him back to his suffering patients.

In a long analysis of dementia, Deisseroth contemplates the way optogenetics has revealed that valence—the sense of value that accompanies brain states—is made across long-range connections in the brain. He notes that a memory must be accompanied by feelings in order for it to have meaning and salience. In dementia, memory falls away, leaving only feelings of helplessness. Optogenetics can show that those feelings exist and suggest that they might have once been tied to memories of a life with meaning, but it cannot restore that which is lost when memory fails nor can it alleviate the burdens borne by individuals with dementia or those who care for them.

In a chapter describing eating disorders, Deisseroth editorializes the explicit ambiguity his science creates in his book. There is, he writes, “a key difference between experiments with optogenetics and realities of the disease.” Optogenetics allows scientists to turn cells off and on. But neurons do this themselves all the time without the help of a scientist, and no one knows how. There is something hollow in our struggle to make truth from mind.

Deisseroth never establishes balance between the cold rationality of his technology and the heroic and emotive struggles his prose otherwise records. Indeed, for all of their literal brilliance, the optogenetic experiments he discusses ultimately render our psychic struggles harder rather than easier to understand.

These tensions are familiar in books of this genre that foreground case histories of mental disease to explore humanity’s ever-shifting natures and boundaries. However, Projections sits awkwardly in this tradition because it breaks from the authoritative objectivity that typically guides readers. Deisseroth instead embraces the fictional and poetic and leaves it up to us to decide what and where authority on such matters resides. The result is a trenchant story about human emotions that may leave some readers wanting answers where there are none.

About the author

The reviewer is associate director of the Clarkson Honors Program, Clarkson University, Potsdam, NY 13699, USA.