Science journalist Michael Lemonick tells the story of Lonnie Sue Johnson, a woman whose unique memory loss has led to groundbreaking studies in neuroscience, learning, and memory. Lemonick is the opinion editor at the Scientific American and his new book is “The Perpetual Now: A Story of Amnesia, Memory, and Love.”

After an infection burned through Johnson’s hippocampus, she was left with almost no memories, and the inability to form and retain new ones. “I began to understand that unlike H.M., she had a vastly rich trove of memories and abilities that neuroscientists could go about testing and deepening our understanding of memory,” Lemonick said.

Domenech and Lemonick discuss our brains’ ability to fabricate memories that didn’t happen, as well as forget ones that did. “Every time we retrieve a memory, the actual memory itself gets mixed in with stuff we have learned subsequently,” Lemonick said.