In the past several weeks I’ve often wondered what Bruce McEwen would make of the current state of the world. McEwen was a neuroscientist and endocrinologist at the Rockefeller University who spent his career studying how stress impacts the brain. In 1968 he and his team made the seminal discovery that stress hormones such as cortisol enter the brain and effect neurological function. Exposure to chronic stress factors in the environment creates allostatic load, a term McEwen coined in 1993. Enough stress over long periods leads to measurable changes in brain chemistry and gene expression—and not necessarily for the better. McEwen passed away on January 3 of this year at the age of 81.