At the height of her career, Barbara Lipska --- a leading expert on the neuroscience of mental illness --- was diagnosed with melanoma that had spread to her brain. Within months, she exhibited dementia- and schizophrenia-like symptoms that terrified her family and coworkers. But miraculously, the immunotherapy her doctors prescribed worked, and Lipska returned to normal. With one difference: she remembered her brush with madness with exquisite clarity. Lipska draws on her extraordinary experience to explain how mental illness, brain injury and age can distort our behavior, personality, cognition and memory. She tells what it is like to experience these changes firsthand. And she reveals what parts of us remain, even when so much else is gone.