In “Extremely Loud and Incredibly Close” by Jonathan Safran Foer, the protagonist reflects on the interconnectedness of people’s emotions and physical responses. He muses on the peculiar idea of everyone’s hearts synchronizing, reminiscent of how women living together often experience synchronized menstrual cycles. This thought presents a sense of mystery about the human experience and how closely linked individuals can be in their emotional states.

The quote highlights the wonder and complexity of human relationships. It captures the protagonist's curiosity about shared experiences, while also acknowledging a certain discomfort with the intimate nature of these connections. Foer skillfully invites readers to contemplate the invisible ties that bind us, suggesting that our emotional lives might be more intertwined than we realize.