Biographical Memoirs Volume 67 (1995) / Chapter Skim
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Herbert Spencer Gasser
Herbert Spencer Gasser
Pages 146-177
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From page 147... ...
This long-overdue memoir has been written almost thirty years after his death. We both knew him at the Rockefeller Institute and have had access to extensive archival material.
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From page 148... ...
Fine craftsmanship remained a lifelong interest. Young Gasser had a simple box Kodak camera that he supplementecl with much "improvised equipment." As he remembered: "This experience later turned out to be a good training for a physiologist." In accordance with his father's wishes, Gasser studied at the state normal school in Platteville.
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From page 149... ...
Professor William Howell suggested that he work on mechanisms of blood clotting, studies that he clip not complete until after leaving Baltimore. Howell confirmed Gasser's results.
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From page 150... ...
While the amplification was sufficient to detect the nerve action potentials with the string galvanometer, the latter was too slow to record the fast potential changes with fidelity. A recording device with sufficient speed did exist, the cathode ray or Braun tube, in which a beam of electrons was deflected by potentials applied to pairs of vertical or horizontal plates.
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From page 151... ...
Then there occurred an event crucial in its significance." This crucial event occurred in 1920, when both the Physical Society and the American Physiological Society happened to meet at the same time in Chicago. Professor Horatio Williams, of Columbia, told Gasser there would be a paper read at the Physical Society meeting that wouIc!
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From page 152... ...
Ever afterward, Gasser never had any doubt about the direction he would follow." It was evident from these earliest studies that the action potential recorded from the frog sciatic nerve was compound in nature (i.e., it resulted from the summation of potential changes in many individual axons)
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From page 153... ...
I~apique was well-known for his work on nerve and muscle excitation and for his ideas about "chronaxie," an indirect measure of the speed of voltage change of the tissue to an applied current pulse. When Gasser showed his records of compound action potentials to Lapique, "he suggested forthwith that the velocity differences might be associated with the sizes of the fibers." His visit with Lapique was the only one during the European trip that had direct relevance to Gasser's long-range interests and lect to a special publication.
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From page 154... ...
In 1924 a paper titled "The Compound Nature of the Action Current in Nerve as Disclosed by the Cathode Ray Oscillograph" was authored by ErIanger and Gasser "with the collaboration in some of the experiments of George H Bishop." This important paper was a milestone in the development of knowIedge about the physiology of peripheral nerve.
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From page 155... ...
The successive elevations in the potential record were produced by axons conducting progressively more slowly; the deflections were called alpha, beta, gamma, and delta. The best fit between the actual compound action potential and the reconstructec3 plot was obtained when the action potential in the individual axon was given a duration of ~ millisecond, the amplitude of the externally recorcled action potential in each axon was maple proportional to axonal size, and conduction velocity was related directly to axonal diameter.
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From page 156... ...
C fiber action potentials were longer in duration than those in A fibers; the proportionality between conduction velocity and diameter was also different, although the relationship appeared to be linear. Myelinated preganglionic sympathetic fibers were designated B fibers.
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From page 157... ...
Also, the size of the afterpotentials depended on the amount of preceding activity. The excitability changes produced by the relatively long lasting positive after-potentials in peripheral nerve fibers en cl their augmentation by preceding repetitive activity were of interest because they might help explain certain Tonglasting excitability changes in the central nervous system.
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From page 158... ...
Many were the hours spent over endless cups of coffee in the physiology seminar room, in the cafeteria (then run on a leisurely schedule in the medical school without a closing hour for lunch) , in friends' houses or in neighboring or downtown restaurants; and many were the diagrams drawn on odd envelopes, on cafeteria checks, on paper napkins, or even on restaurant tablecloths.
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From page 159... ...
When Gasser moved to Cornell, the direction of his work changed slightly. With Grundfest he investigated mammalian peripheral nerve fibers and found important quantitative differences between amphibian and mammalian nerve.
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From page 160... ...
Charles Stockard, professor of anatomy at Cornell, en cl a member of the Board of Scientific Directors of the Rockefeller Institute, had suggested his name. The offer surprised Gasser, and he doubted his administrative abilities.
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From page 161... ...
give Gasser free time for his own laboratory work were fulfiller! fairly well for six years.
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From page 162... ...
Gasser's own laboratory work represented a continuation of his research at Cornell. In 1938 he published papers on recruitment of nerve fibers and on properties of mammalian nerve fibers of slowest conduction with Grungiest and Richards en c} in 1939 an article on axons as samples of nervous tissue.
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From page 163... ...
By then the aging laboratories were in need of refurbishing. Gasser designed standardized laboratory furniture, beautiful oak cabinetry of modular dimensions.
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From page 164... ...
This had been a key factor in attracting Gasser himself to the Institute. Some of his remarks indicate how strongly he was committed to this policy: The product of the Rockefeller Institute is new knowledge....
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From page 165... ...
Concerned that his research might not be optimal for training a young scientist, Gasser decided to work without a coliaborator. The major aim of his research after retirement was to continue exploring the structure and function of unmyelinated axons in peripheral nerve.
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From page 166... ...
This turned out to be quite limited, suggesting that interactions from this cause were not likely to be important. Unmyelinated axons in peripheral nerve may be sensory, their cell bodies lying in the dorsal root ganglion, or efferent, postganglionic sympathetic fibers en route to the periphery.
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From page 167... ...
Although afferent, they showed action potentials that differed from those of mammalian dorsal root C axons, showing a simple form consonant with all of the axons having nearly the same diameter. Gasser also sought an answer to a problem in the recording of the compound action potential, which had long botherec3 him.
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From page 168... ...
the principle that there are two times for working on a problem before anyone has thought of it and after everyone else has left it. As a result, Gasser was always the innovator or the finalist." GASSER IN PERSON As Director of the Rockefeller Institute, Gasser was a striking figure.
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From page 169... ...
By the time he retired in 1953, grant support had expanded considerably, and Gasser's reservations seemed old-fashioned to many. There was then an abundance of governmental money, and research of quality found support with proposals that were liberally and flexibly reviewed.
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From page 170... ...
The homemade cathode ray tube and its trundling to the XIII International Congress of Physiology in Boston, 1929, is described in Hallowell Davis' memoir of Joseph Erlanger in Biographical Memoirs, vol.
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From page 171... ...
Erlanger) 1946 Royal Society of London, Foreign Member Royal Swedish Academy of Sciences, Foreign Member 1947 Finnish Academy of Sciences, Foreign Member Academic Royale de Medicine de Belgique, Corresponding Member American Society of Electroencephalography, Honorary Member 1948 American Academy of Arts and Sciences Accademia della Scienze dell' Istituto di Bologna, Corresponding Member 1949 Physiological Society (British)
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From page 172... ...
72 948 949 953 959 BIOGRAPHICAL MEMOIRS Sc.D., Oxford University Sc.D., Harvard University Doctor honoris cause, Universite Libre de Bruxelles Doctor of Medicine, Honorary, Universite Catholique de Louvain Honorique de docteur, Universite de Paris Sc.D., The Rockefeller University PROFESSIONAL ORGANIZATIONS American Physiological Society American Association for the Advancement of Science, Fellow Society for Experimental Biology and Medicine, President, 1937-39 Harvey Society, President 1940-42 Association for Research in Nervous and Mental Diseases American Society of Pharmacology and Experimental Therapeutics Association of American Physicians History of Science Society New York State Society for Medical Research American Neurological Association (Associate Member)
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From page 173... ...
Physiological action currents in the phrenic nerve. An application of the thermionic vacuum tube to nettle physiology.
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From page 174... ...
The compound nature of the action current in nerve as disclosed by the cathode ray oscillograph.
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From page 175... ...
The component of the dorsal root mediating vasodilation and the Sherrington contracture.
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From page 176... ...
Hughes. Afferent function in the group of nerve fibers of slowest conduction velocity.
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From page 177... ...
Properties of mammalian nerve fibers of slowest conduction.
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