The other day, my friend Kristina told me that one evening she unintentionally locked her husband in a downstairs part of their house. She had known he was down there, but while distractedly locking the door for the night, forgot completely. She didn’t realize what she’d done until she saw a text from her husband the next morning asking her to please let him out. “I couldn’t believe I did that to him,” she says. “I was stunned and alarmed that I had no awareness, in the moment or afterward, of what I had done.” Kristina’s is one of many stories I’ve recently heard from people suggesting they’re having more trouble staying focused, making decisions, or remembering things. I’ve experienced this myself—misplacing keys, forgetting appointments, and leaving lights on in vacated rooms. When it comes to work, I’m less focused and have trouble getting things done. Perhaps it’s because I spend …