It was a panel assembled to discuss ‘contagion.’ The impetus could be traced back to news reports about the Zika virus and what it is believed able to do to the human brain during gestation. Because of my background in epidemiology and public health (along with brain function) I’d been invited to participate. One attendee asked: “What does it mean when you say something is contagious?” I responded that the word indicated that something is able to be transmitted from one person to another, directly or indirectly. It doesn’t mean that it will be transmitted 100 percent of the time but that there is a higher risk of that happening. Another panel member added that typically the term used to be applied somewhat exclusively to the transmission of organisms or diseases from one person to another. A third panel member quickly interjected that all manner of things—organisms, ideas, perceptions, financial contagion, and even habits are transmissible. That opened a can of worms that resulted in some heated ‘brain exchanges’ between audience members. Talk about lively. Talk about ideas for next week’s blogs—and what studies have indicated can be transmitted among people. Stay tuned.