Background

Alexander Forbes was born on May 14, 1882, in Milton, Massachusetts, United States. He was the son of William Hathaway and Edith (Emerson) Forbes.

Education

Forbes graduated from Milton Academy in 1899 and then attended Harvard. He studied with Charles S. Sherrington at Liverpool and with Keith Lucas at Cambridge.

Career

After graduating, Alexander returned to Harvard Medical School, where he remained until 1948. After 1948 he was professor emeritus and continued his research in the Harvard biological laboratories.

Forbes’s primary scientific interest was neurophysiology, but equally strong was his love of the outdoors, the woods, rivers, and hills of New England, particularly the coast of New England and Labrador. He made contributions to navigation and, at the suggestion of Sir Wilfred Grenfell, he mapped the coast of Labrador by aerial photography, using the technique of oblique photogrammetry. He also served with the United States Navy in both World Wars. In the first, he installed radio compasses, and in the second he mapped an aerial route across northern Greenland.

Forbes was a scientific amateur in the best sense of the word. As a man of independent means, he engaged in his laboratory experiments and explorations because he loved them. He did little formal teaching. Not only did he defray much of the expense of his own activities, but for many years he anonymously supported others in the department of physiology.

Forbes’s greatest contributions to neurophysiology came early in his career. He was a technical innovator. About 1912 he installed what was probably the first string galvanometer in the New England area for the accurate measurement of the time relations of spinalcord reflexes. Later, using his experience with radio compasses, he developed a capacity-coupled electronic amplifier for greater sensitivity, and in 1920 he became the first to report the use of electronic amplification in a physiological experiment.

The paper by Forbes on the flexion reflex of the decerebrate cat, timed by means of the string galvanometer, was a landmark in neurophysiology. His most influential paper was a review entitled The Interpretation of Spinal Reflexes in Terms of Present Knowledge of Nerve Conduction. The properties of the spinal reflexes were chiefly those described by Sherrington and his pupils. The knowledge of nerve conduction was developed chiefly by Lucas and E. D. Adrian. Forbes visited Adrian in 1921.

Forbes’s great contribution was to unite these two schools of thought and experimentation and thereby establish the form and direction of a major segment of American neurophysiology. In his paper, he provided a coherent, consistent interpretation of the major features of reflex activity. Actually, many of the interpretations were erroneous, as Forbes readily admitted, but his ingenious suggestions inspired experiments and theorizing for at least twenty years. Through his influence on Norbert Wiener, Arturo Rosenblueth, and others, he contributed significantly to the development of the science of cybernetics.

Forbes himself considered his single most important scientific contribution to be the final establishment of the all-or-none law of nerve conduction. The experiments, planned by Forbes and carried out by his collaborators, showed that the strength of a nerve impulse is not diminished after it has passed through a local region of partial narcosis where the impulse was weakened but not extinguished. The impulse is a chain reaction, with local contribution of energy in amounts depending on the local condition of the nerve fiber, not on the previous history of the impulse elsewhere. The idea had been formulated previously by Adrian, but with inadequate experimental support. Forbes’s experiment was performed independently and simultaneously, with the same result, by Genichi Kato and his associates in Japan.

Forbes’s laboratory became a center for the training of both American and European neurophysiologists. Forbes participated in the early use of microelectrodes (large ones by modern standards) and fostered studies of the auditory system and the early development of electroencephalography in the United States. His studies of electrical responses of the brain under Nembutal narcosis paved the way for far-reaching later developments.

Achievements

• Alexander Forbes was a pioneer in neurophysiology research in the United States. he is best remembered as the man who united two lines of British thought, those of Sherrington and of Keith Lucas, and established them firmly in the United States. In addition to his medical research on the function of the central nervous system, he studied and wrote about navigation with special emphasis on aerial mapping of coastlines. For this achievement, he was awarded, in 1938, the Charles P. Daly Medal of the American Geographic Society.

Membership

Forbes was a member of the American Physiological Society, the American Academy Arts and Sciences, the American Philosophical Society, the National Academy of Sciences.

Personality

Forbes was a man of varied interests, kindly good humor and with the perennial sparkle of youth, and, to the amazement and envy of his contemporaries, he continued vigorously in many of his activities until within a year of his death.

Physical Characteristics: Alexander's health was superb. His only physical affliction was a moderate hearing loss, dating from about 1908.

Interests

• Sport & Clubs

  Yachting, skating, skiing, rock climbing, and canoeing

Connections

In 1910 Forbes married Charlotte Irving Grinell of New York. The couple had four children.

Father:

William Hathaway Forbes

Mother:

Edith (Emerson) Forbes

Spouse:

Charlotte Irving Grinnell

Daughter:

Janet Forbes

Son:

Alexander Irving Forbes

Daughter:

Florence Emerson Forbes

Daughter:

Katharine Forbes

References

• Dictionary of Scientific Biography