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Peter Dews died on 2 November 2012, in the Brigham and Women’s Hospital, a few short steps from the Harvard Medical School, where he spent the majority of his professional career. That short, physical distance belies a vast academic expanse traveled by Dews over the course of his career from bench science in physiology and pharmacology, to behavioral pharmacology, and to experimental psychology. Ultimately, through membership on various national committees and in professional organizations, he provided counsel on a wide variety of behavioral science, public health, and mental health issues involving pharmacology, toxicology, research training, drug dependence, neuroscience, and space science.

Dews attended medical school at the University of Leeds in the United Kingdom, where he received his Bachelor of Medicine and Bachelor of Surgery degrees. He then joined the subdepartment of Pharmacology at Leeds which at that time was headed by Professor W.A. Bain. At Leeds, Dews studied, among other things, the pharmacology of a marijuana extract. Challenged with quantifying the behavioral effects of the substance in the absence of suitable procedures had a large and lasting impact, as it provided him with an appreciation of the difficulties inherent in objectively studying the effects of drugs on behavior.

Dews subsequently spent time at Oxford with J.H. Burn (1946) and in Edinburgh with J.H. Gaddum (1947). He came to the United States in 1948 when he was offered a two-year Research Fellowship at Burroughs Wellcome in Tuckahoe, New York. It was at Wellcome that he conducted his first published study on the behavioral effects of drugs: locomotor activity that he termed “voluntary behavior” (Dews, 1953). He subsequently accepted a Fellowship at the Mayo Foundation, where he served from 1950 to 1952 in the laboratory of Charles Code, and earned a Ph.D. in Physiology (1951) from the University of Minnesota. For the next year, he worked with Joseph Berkson in the Division of Biometry and Medical Statistics at the Mayo Clinic, during which, he formed an interest in statistical analysis and error estimation that was later renewed when he examined risk assessment in behavioral toxicology.

When Professor Otto Krayer gave a Mayo Foundation Lecture in 1952, he recruited Dews for a position as Instructor in Pharmacology at Harvard Medical School. Krayer wanted someone for his Department who was interested in CNS pharmacology, and as noted above, Dews had published a paper on behavior in mice. When Dews arrived at Harvard in 1953, Krayer suggested that Dews call on B.F. Skinner in the Department of Psychology at Harvard University. Skinner had for some time been promoting to Krayer behavioral techniques that he thought would be useful for pharmacologists interested in the behavioral effects of drugs. Dews met with Skinner only briefly, and then C.B. Ferster provided a tour of the laboratory. Although Dews knew little about the ongoing behavioral research, he was impressed by the functional character of the studies in Skinner’s laboratory. The manner in which behavioral responses were recorded cumulatively in real time strikingly resembled the kymograph recordings that were of enormous value to physiology and pharmacology. Dews sensed that this approach might be a way to study the effects of drugs on behavior in an objective manner and was precisely what had been missing in the earlier fruitless attempts to characterize behavioral effects of the marijuana extract.

Ferster invited Dews back to try out the effects of drugs on various performances being studied in pigeons, and several of these impromptu experiments were subsequently published in Ferster and Skinner’s Schedules of Reinforcement (1957). With the generous accommodation of equipment from Skinner’s laboratory, Ferster’s initial mentorship, and Krayer’s committed and continuing support for what must have seemed bizarre in a traditional pharmacology department, Dews launched a program of objective and quantitative studies of the behavioral effects of drugs and in doing so promoted the emergence of behavioral pharmacology as a rigorous basic science discipline.

His initial experiments established that the schedule of reinforcement that maintained a readily repeated response could play a critical role in determining the effects of pentobarbital (Dews, 1955). Not only were the dose-dependent effects on performances maintained under two different schedules of reinforcement dissimilar, but there was a range of doses over which responding was increased under one schedule and decreased under the other. The effects of a drug on behavior could be completely opposite, depending on the schedule of reinforcement that controlled the behavior. In subsequent research, Dews investigated the effects of drugs on performances under the control of simple and complex discriminative stimuli and the behavioral effects of psychomotor stimulants. In the latter studies, Dews discovered that psychomotor stimulants could increase or decrease the probability of behavior depending on the probability (or rate) of the behavior before drug administration. This “rate-dependency principle” had precedents in the physiological pharmacology being studied in the department (e.g., Langer and Trendelenburg, 1964), and formed an important launching point for many subsequent studies of the behavioral effects of drugs by Dews and many others.

In the years that followed, Dews put together a productive laboratory at Harvard, first within Krayer’s Department of Pharmacology and later in the Department of Psychiatry. With the addition of W.H. Morse and subsequently the late R.T. Kelleher the laboratory thrived. Although there always was an emphasis on studies of the behavioral effects of drugs, consistent with Krayer’s receptive appreciation of topics traditionally thought of as outside the realm of pharmacology, the subjects studied by Dews and his colleagues ranged widely and included behavior controlled by schedules of reinforcement, environmental influences on vision, behavioral and environmental influences on cardiovascular function, substance abuse, and behavioral toxicology.

Perhaps one of Dews’s considerable strengths was that he was not formally trained in psychology. Being a self-admitted “mere pharmacologist,” he was not constrained by psychological theory, and he approached behavioral studies with methods and techniques that appealed to his sensibilities as an experimentalist. Dews immediately felt an affinity for Skinner’s functional approach as a way to study drugs in objective and physical terms as opposed to subjective and mentalistic constructs. Most important to Dews was that the methods produce objective and quantifiable data and that studies emphasized functional relations between independent and observable dependent variables. Characterizing all of his endeavors was a demand for uncompromised behavioral and pharmacological science that relied on sound principles. This approach continues to invigorate the best work in behavioral pharmacology, and surely, must be viewed as the legacy of Peter B. Dews.

Dews is survived by his wife, Grace; daughter, Pamela Rentschler; sons, Kenneth, Alan, and Michael; a sister, Jean Hilditch, in England; nine grandchildren; and a great-grandchild. A more extensive description of Dews’s life and scientific contributions is available at the following web site: http://www.aspet.org/Behavioral-Pharmacology/Dews-Award/