“The most remarkable thing” about Dr. McEwen, he added, in a phone interview, “is that he started off as a cell biologist, with his first paper on muscle biochemistry published in 1959 in Science, and over the last couple of decades his work was more about why crappy childhoods make for adult brains that don’t work well.”

Dr. McEwen discussed allostatic load in 2000 in the journal Neuropsychopharmacology, writing:

“In anxiety disorders, depressive illness, hostile and aggressive states, substance abuse and post-traumatic stress disorder (PTSD), allostatic load takes the form of chemical imbalances as well as perturbations in the diurnal rhythm, and, in some cases, atrophy of brain structures.

“In addition,” he went on, “growing evidence indicates that depressive illness and hostility are both associated with cardiovascular disease (CVD) and other systemic disorders. A major risk factor for these conditions is early childhood experiences of abuse and neglect that increase allostatic load later in life and lead individuals into social isolation, hostility, depression and conditions like extreme obesity and CVD.”

By the end of his career Dr. McEwen had expanded his research to look at the impact of stress on communities, finding that chronic stress disproportionally affected marginalized people and increased their risk of illnesses.

Five years ago, he teamed up with his brother, Craig McEwen, a professor emeritus of sociology at Bowdoin College in Maine, to study the sociological implications of chronic stress.

“We know that environmental complexity changes the brain,” Bruce McEwen said in an interview recorded by Rockefeller University, and that it “comes to haunt us in terms of socioeconomic status, poverty and things of that sort.”

At his death — caused by complications of a stroke, a Rockefeller spokeswoman said — Dr. McEwen was the Alfred E. Mirsky professor and head of the Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology at the university.