A Newsweek article by Soo Kim covers the SONA, an AI-powered ear device its founder Jane Ollis says reduces stress and improves sleep by reading heart rate variability and breathing, then stimulating the vagus nerve accordingly, in 10-to-20-minute daily sessions. Medical experts call the closed-loop approach plausible and probably safe but unproven for sleep, and want randomized sham-controlled trials to show real-world benefit.