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Horsley Gantt was born in 1893 in Wingina, Virginia, USA, and received his M.D. in 1920 from the University of Virginia, at Charlottesville. Gantt began with his professional career at the University of Maryland in Baltimore studying “liver pathology,” but his interest shifted after serving for a year, from 1922 to ’23 as Medical Chief of the Petrograd (now Saint Petersburg) Unit of the American Relief Administration in Russia, at the time in the Union of Soviet Socialists Republics.

In 1924, Gantt joined Ivan Petrovich Pavlov and for five years he was conducying research in conditioning at his Institute of Experimental Medicine.  After returning to the United States he continued his research in conditioning from 1930 to 1958 as Director of the Pavlovian Laboratory, The Johns Hopkins University of Medicine, and subsequently, from 1959 to 1980 as Senior  Scientist in the Pavlovian Research Laboratory of the Veterans Administration Hospital  at Perry Point, Maryland. He conducted his research primarily in animals, but also in man, including patients with mental pathology.  He held appointments during the corresponding periods in the departments of psychiatry at Johns Hopkins and at the University of Baltimore.

Gantt began his research in psychopharmacology in the mid-1930s. Over a period of forty years, he was involved first in studying “drug effects on conditional and unconditional reflexes” in general, then in studying the differential effects of drugs  on “autonomic and somatic conditioned reflexes,” and ultimately in the study of  “conditioning of drug effects.” His findings with alcohol, acetylcholine, adrenaline, amphetamine, caffeine, chlorpromazine and reserpine in the first set of studies, were supportive of Pavlov and his associates’ reports that drug effects were dependent on the “temperamental type” of animals. In the course of these studies he showed that acetylcholine improved conditional reflexes more in “neurotic” than in “normal” dogs, whereas adrenaline was less disruptive in “normal,” than in “neurotic” animals. In the second set of studies, Gantt and his associates revealed that some drugs, for example chlorpromazine, reserpine and 5-hydroxytryptophan, influenced motor and cardiac conditional reflexes to the same degree, whereas others, for example mescaline, meprobamate and metrazol, affected autonomic conditional reflexes preferentially, and others again, for example, morphine had a preferential effect on motor conditional reflexes. Finally, in the third set of studies, Gantt and his associates demonstrated that there was conditioning only to the central effect, but not to the peripheral effect of dugs. Thus, cardiac conditional reflexes could be formed to the central effect of bulbocapnin, but not to the peripheral effect of acetylcholine.

Gantt’s studies stimulated interest in “Pavlovian” research, leading to the founding of the Pavlovian Society of North America in 1955 and to the Collegium Internationale Activitatis Nervosae Superioris about ten years later. Gantt was founding President in both of these societies.  

Horsley Gantt died in 1980 at age 83.

Bridger WH, Gantt WH. Effect of mescaline on differentiated conditional reflexes. Am J Psychiatry 1956; 113: 352-60

Freile M, Gantt WH. Effect of adrenaline on excitation, inhibition and neuroses. Trans Am Neurol Assoc 1944; 70: 180-1

Gantt WH. Effect of alcohol on cortical and subcortical activity measured by the conditional reflex method. Bull Johns Hopkins Hosp 1935; 56: 61-83

Gantt WH. Psychopharmacology and conditional reflexes. Cond Reflex 1970; 5: 109-18

Perez-Cruet J, Gantt WH. Conditional reflex electrocardiogram of bulbocapnine. Conditioning of the T wave. Am Heart J 1964; 67: 61-72

Stoff DH, Bridger WH.  Horsley Gantt, the first American psychopharmacologist. In: McGuigna FJ, Ban TA, eds. Critical Issues in Psychology, Psychiatry and Physiology. A Memorial to W. Horsley Gantt. New York: Gordon and Breach Science Publishers; 1987, pp. 177-87.

Thomas A. Ban
August 1, 2013