LSD may trigger euphoria and joy in some, and anxiety, paranoia and delusions in others. In very small doses, though, some people have found it can boost productivity while providing a sense of calm. That was Ayelet Waldman’s experience. She joins us to talk about her monthlong experiment with microdosing – and about the history and mythology of LSD – which she writes about in “A Really Good Day: How Microdosing Made a Mega Difference in My Mood, My Marriage, and My Life” (Knopf).