According to the New York Times, he was "known for his scientific work, including fundamental contributions to the understanding of autism, Tourette's syndrome and other illnesses, and for his leadership in bringing together the biological and the psychological approaches to understanding psychiatric disorders in childhood"; his work "reshaped the field of child psychiatry".
[3] According to his son-in-law and later colleague Andrés Martin, Cohen was an "observant Jew with deep ties to Israel and a lifelong preoccupation with the Holocaust",[4] who described himself as a "Jewish boy of humble origins growing up in Chicago".
[1] He obtained his MD in 1966 from Yale School of Medicine, and completed his general and child psychiatry residency at Massachusetts Mental Health Center and Children's Hospital, in Boston and Washington, DC.
[1][3] According to The New York Times, Cohen said that "as a student he honed his fund-raising skills working as a copy writer for a mail order catalog, extolling the virtues of women's hats and other merchandise".
[7] Cohen was named the director of the Yale Child Study Center in 1983—a position he held until his death in 2001.
[2] As a "pioneer" in autism and Tourette syndrome research, he proposed treatments for TS which "opened new avenues to treating and understanding the disorder".
[1] He held additional chair appointments with the Child Health and Development Institute, the International President of the Telefon Azzuro Foundation in Italy, and Schneider Children's Hospital of Israel.
[2] Colleagues said Cohen "blended a profound spirituality with a broad understanding of science and clinical work";[1] friend Joe Lieberman described him as someone who "did more in his 61 years than most anyone else could ever hope to accomplish in a lifetime ... a true professional, and caregiver and friend to the thousands of people who had the good fortune of knowing him" and a person who "dedicated his life to helping children and adolescents ... working tirelessly to develop and promote programs to assist children".
[3] Colleague James F. Leckman said, "He fostered the development of the next generation of academic child psychiatrists from many countries, in Europe, Korea, China, as well as Israel",[1] and described him as "committed to forging closer ties between Israel and Palestine through contacts and visits with various psychiatrists, psychologists, and social service agencies active in Gaza and the West Bank.