Origins

The effects of some drugs affecting behavior have been described as far back as there is written record and there are many more agents with an ancient pedigree. Opium, for instance, has been lauded by physicians for millenia. Some have been incorporated into religious rituals (e.g., mescaline for some Amerindians). Until recently, however, knowledge of behavior-affecting drugs was limited to descriptions of what could be seen in people under the influence of the drugs, supplemented by what the subjects told observers. Even when pharmacology developed into a flourishing scientific field, by the end of the 19th century, behavioral pharmacology languished and it was not until the 1950s that behavioral pharmacology became established as a recognized field. Even later, a respected textbook of pharmacology cited Shakespeare on the pharmacology of alcohol. Scientists do not generally cite artistic descriptions as their authority.

As is usual when a new field of science emerges, it is easy to identify prior work that presaged it. For example, the work of Russian Pavlovian physiologists in the early 20th century was aimed explicitly at developing a science of behavior and extended to studying effects of drugs on behavior. Working primarily on dogs, interesting and influential results were obtained, but the line of work did not lead to a recognized field of pharmacology. The failure was likely due to the rigidity of the framework: All behavior had to be identified as reflexive: unconditioned or conditioned reflexes. That is, behavior consists only of responses to stimuli. Such a view not only is contrary to common experience but also frustrated scientific progress.

Another example is work in Baltimore from 1915 onwards. The vision was clear. A pharmacologist wrote: ''The effect of drugs on psychological functions has been the subject of remarkably little investigation on the part of either psychologists or pharmacologists • • • so that the field of 'psychopharmacology' is virgin soil, full of opportunities.'' Studies on movement capabilities of rats led to methods that were applied to pharmacology. Rats climbed a rope to reach a platform with food and the effects of the drugs on climbing time were measured. Although, again, the field of behavioral pharmacology did not develop in the short run, it is interesting to trace the subsequent history of the methods. After being largely ignored for a couple of decades, they were revived by their originator (and modified, of course) in the 1940s and then applied by scientists at a drug company United States. They were then adapted (and modified) by scientists at a drug company in France. There, they helped in the discovery of the drug chlorpromazine, which in turn was important in the rapid development of behavioral pharmacology in the 1950s.

In retrospect, a paper published by B.F. Skinner and colleague in the psychological literature in 1937 presaged much of the behavioral pharmacology of the 1950s. It passed unnoticed by pharmacologists.

Why was behavioral pharmacology late to develop? Automatic programming was used extensively in behavioral pharmacology from the first. Automatic programming had been in use in industry since at least the 1920s and had been applied to behavioral research in the 1930s, so what eventually started in the 1950s could have started in the 1930s. However, it seemed self-evident to researchers interested in the behavioral effects of drugs that the drugs must affect primarily the ''higher'' functions of the brain, especially functions that came to be loosely called "cognitive." Learning, in particular, was assumed to be a frequent target of drugs. Higher functions were vaguely associated with higher organisms, particularly humans. (Paradoxical ly, what we know about learning as a biological phenomenon is compatible with learning being a primitive function with a long evolutionary history: It is not a peculiarly human phenomenon.) However, when researchers tried to measure such effects on higher functions, results were ambiguous, difficult or impossible to interpret, and did not seem to lead anywhere. Therefore, researchers were discouraged and abandoned the line of work, so the field did not develop. The truth is that it is usually bad to approach a scientific field with some of its basics accepted as self-evident because they are quite likely wrong. For example, it was considered self-evident that the earth was flat and stationary at the center of the universe, but approaching the study of the earth and the universe with this conviction was not hopeful. What may seem to be self-evident about behavioral phenomena may be equally false. It was not until behavioral phenomena were approached without prejudice and respected as the appropriate subject matter to be studied for drug effects on behavior that behavioral pharmacology could begin. Preconceptions had diverted attention from the actual subject matter.

It is not clear why behavioral pharmacology started just when it did. It has been suggested that the quantitative graphic method of displaying behavioral phenomena in real time, the cumulative record—the type of display given by a kymograph and as such familiar to pharmacologists of the time—was seminal. Displays of this kind are compelling and informative and do seem to facilitate the development of a field, since physiology was stimulated by the introduction of the kymograph in the mid-19th century. Such displays had been present in behavioral research for a decade and a half. They doubtless facilitated behavioral pharmacology. Whatever the reasons for behavioral pharmacology starting in earnest when it did, it is clear that the effort was launched before chlorpromazine came on the scene. It is equally clear that the great growth of behavioral pharmacology in the next few years was helped by the impact of the introduction of chlorpromazine and one or two other drugs.

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Breaking Bulimia

We have all been there: turning to the refrigerator if feeling lonely or bored or indulging in seconds or thirds if strained. But if you suffer from bulimia, the from time to time urge to overeat is more like an obsession.

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