Deisseroth is an internationally acclaimed professor of bioengineering and psychiatry at Stanford, but his true passion is clinical psychiatry, and it is the stories of his patients that form the backbone of Projections. Through these case studies, he tells the larger story of how we can understand the physical and biological origins of human emotion in the brain. As such, he describes vividly how humans experience feelings in the ancient circuits of our brains and in the poignant moments of suffering in our daily lives. The stories of Deisseroth's patients are rich with humanity and shine an unprecedented light on the self and the ways in which it breaks down. A young woman with an eating disorder reveals how the mind can rebel against the brain's most primitive drives of hunger and thirst; an older gentleman, smothered into silence by depression and dementia, shows how humans evolved to feel joy and its absence; and a lonely Uyghur woman far from home teaches the importance of deep social bonds.