Born Janet Pearson Cox in Bronxville, New York to Vernon Cox, a schoolmaster at
St. Bernard's School in Manhattan, and Mary Bostwick Cox, a
Wellesley College graduate in Art History. She attended Bronxville High School (graduating in 1948) and Wellesley College (class of 1952). Though she was working as a model and preparing for a career in
fashion merchandising, her encounter with
Sydney J. Freedberg, her professor at Wellesley, convinced her to follow a career in art history. She followed Freedberg to Harvard, where she did her MA and PhD under his supervision. She won a two-year
Fulbright Fellowship in 1954, which led to her meeting with a young opera student,
Anna Moffo, who became her lifelong friend. In 1961–63 she was a member of the first class of Fellows to
Villa I Tatti, The Harvard Center for Italian Renaissance Studies. (The other Fellows appointed in that year were Eric Cochrane, Curtis Shell, John Freccero, and David Herlihy.) She held appointments at I Tatti again in 1975–76 and 1990–91. == Scholarly work ==