An award-winning science writer discovers she’s faceblind and investigates the neuroscience of sight, memory, and imagination—while solving some long-running mysteries about her own life.

Science writer Sadie Dingfelder has always known that she’s a little quirky. But while she’s made some strange mistakes over the years, it’s not until she accosts a stranger in a grocery store (whom she thinks is her husband) that she realizes something is amiss.

With a mixture of curiosity and dread, Dingfelder starts contacting neuroscientists and lands herself in scores of studies. In the course of her nerdy midlife crisis, she discovers that she is emphatically not neurotypical. She has prosopagnosia (faceblindness), stereoblindness, aphantasia (an inability to create mental imagery), and a condition called severely deficient autobiographical memory.