His early work focused on dreams. His later work examined the biological mechanisms and risk factors in psychopathology. In 1989, he co-authored Psychopathology with Lee Willerman.
Throughout the 1990's, Cohen wrote about the biological and evolutionary influences of depression.
Cohen also wrote two books on children for both academic and lay readers, framed by the nature versus nurture debate. In these books, he argued that parental influence over a child's development was much less powerful than biological and evolutionary influences. His work suggests that much parental influence is not only weak or transitory but also illusory.
Publications
Cohen DB (1999). Stranger in the Nest: Do Parents Really Shape Their Child's Personality, Intelligence, or Character? Wiley ISBN 0-471-31922-8.
Cohen DB (1995). Out of the Blue: Depression and Human Nature. W.W. Norton & Company; New Ed edition ISBN 0-393-31299-2.
Cohen DB (1981). Sleep and Dreaming: Origins, Nature and Functions (International Series in Experimental Psychology; V. 23) Pergamon Press. ISBN 0-08-027400-5.
Cohen DB (2003). Where Did That Child Come From?: Why Some of Our Children Turn Out So Different from Us & What the Answers Reveal About Our Parenting and Ourselves. Templegate. ISBN 0-87243-258-0.
Willerman L, Cohen DB (1989). Psychopathology. McGraw-Hill College. ISBN 0-07-070311-6.