Rosenblueth, Arturo

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ROSENBLUETH, ARTURO

(b. Ciudad Guerrero, Chihuahua, Mexico, 2 October 1900; d. Mexico City, Mexico, 20 September 1970)

neurophysiology.

Rosenblueth studied at the Franco-English College in Mexico City and at the Medical School of the University of Mexico, then continued his medical studies at Berlin, and then at Paris, where he obtained his medical degree. In 1927 he returned to the Medical School of the University of Mexico and devoted himself to physiological research and teaching. In 1930 he was offered a research fellowship under Walter B. Cannon at Harvard, which led to a long and productive collaboration. Cannon had shown that the “constancy of the internal medium,” discovered by Claude Bernard, reflected a general regulatory function or “homeostasis,” which presumably was operated essentially by the autonomic nervous system. He and Rosenblueth demonstrated this assumption by extirpation of both sympathetic chains of a cat without impairing the animal’s survival. Through many of these delicate operations they elucidated the details of the sympathetic regulatory action, which results from successive nerve impulses that conduct a quantum of chemical mediator into the terminal organ. These minimal doses summate and elicit various effects: vasomotor action, visceral muscle contraction, and hormonal secretion. These experiments decisively confirmed the theory of “chemical mediation,” then frequently questioned.

At the same time Rosenblueth interested Norbert Wiener in the functional analysis of the nervous system. Their first paper (1943) was the starting point of the work that led Wiener to edify the new science of cybernetics. Rosenblueth was elected assistant professor at the Harvard Medical School in 1934. In 1944 he returned to Mexico City as director of research at the new Institute of Cardiology. The collaboration with Wiener had been maintained for nearly ten years. The neurophysiologist brought his knowledge of the coding information carried by the nerve impulse, and the mathematician demonstrated that the information theory adequately describes the coding in every detail. Rosenblueth and Wiener published papers on the mathematical expression of the conduction of impulses in a network of nerve cells, a statistical analysis of synaptic transmissions, psychology and cybernetics, and even the aesthetics of science.

In 1961 Rosenblueth founded, at the National Polytechnical Institute of Mexico, the center for advanced studies. There he successfully promoted interdisciplinary and international research, uniting the Anglo-Saxon and Latin civilizations of America. He was also a philosopher of science. In his last work, Mind and Brain (1970), he showed how all our knowledge of the material universe is based upon coded nerve impulses. All other features ascribed to the universe are essentially mental. Thus Rosenblueth gave a new and clear expression of the classical dualism between mind and brain.

BIBLIOGRAPHY

Rosenblueth wrote three monographs, Autonomic Neuro-Effector Systems (New York, 1937), written with W. B. Cannon; The Supersensitivity of Denervated Structures. A Law of Denervation (New York, 1949), written with W. B. Cannon; and The Transmission of’Nerre Impulses at Neuroeffector Junctions and Peripheral Synapses (Cambridge, Mass., 1950).

Among his more important papers are “The Electric Responses of the Tail Pilomotors and Nictitating Membrane of the Cat,“in American Journal of Physiology, 137 (1942), 263–279, written with D. D. Bond and W. B. Cannon; “The Control of Clonic Responses of the Cerebral Cortex,” ibid., 681–694; “The Action of Electrical Stimuli on the Turtle’s Ventricle,” ibid., 138 (1942), 50–64, written with W. Daughaday and D. D. Bond; “The Influence of Interelectrodal Distance in Electrical Stimulation of Nerve and Striated and Ventricular Muscle,” ibid., 138 (1943), 583–586, written with G. H. Acheson; “The Centrifugal Course of Wallerian Degeneration,” ibid., 139 (1943), 247–254; “Behavior, Purpose and Teleology,” in Philosophy of Science, 10 (1943), 18–24, written with N. Wiener and J. Bigelow; “The Interaction of Myelated Fibers in Mammalian Nerve Trunks,” in American Journal of Physiology, 140 (1944), 656–670; “Recruitment of Mammalian Nerve Fibers,” ibid., 141 (1944), 196–204; “The Role of Models in Science,” in Philosophy of Science, 12 (1945), 316–321, written with N. Wiener; “The Mathematical Formulation of the Problem of Conduction of Impulses in a Network of Connected Excitable Elements, Specifically in Cardiac Muscle,” in Archivos del Institute de cardiologia, Mexico, 16 (1946), 205–265, written with N. Wiener; “An Account of the Spike Potential of Axons,” in Journal of Cellular and Comparative Physiology, 32 (1948), 275–318, written with N. Wiener, W. Pitts, and J. Garcia Ramos: “The Functional Refractory Period of Axons,” ibid., 33 (1949), 405–440, written with J. Alanis and J. Mandoki; “A Statistical Analysis of Synaptic Excitation,” ibid., 34 (1949), 173–206, written with N. Wiener, W. Pitts, and J. Garcia Ramos; and “Purposeful and Non-Purposeful Behavior,” in Philosophy of Science, 17 (1950), 318–326, written with N. Wiener; “The Local Responses of Axons,” in Ergebnisse der Physiologie, 47 (1952),23–69.

Later papers are “Functional Refractory Period of Cardiac Tissues,” in American Journal of Physiology, 194 (1958), 171–183; “Two Processes for Auriculo-Ventricular and Ventriculo-Auricular Propagation of Impulses in the Heart,” ibid., 194 (1958), 495–498; “Ventricular Echoes,” ibid., 195 (1958), 53–60; “Some Properties of the Mammalian Ventricular Muscle,” in Archives internationales de physiologie et de biochimie, 67 (1959), 276–293, written with J. Alanis and R. Rubio; “The Adaptation of the Ventricular Muscle to Different Circulatory Conditions,” ibid., 67 (1959), 358–373, written with J. Alanis, E. Lopez, and R. Rubio; “The Two Staircase Phenomena,” ibid., 67 (1959), 374–383; “Tetanic Summation in Isotonic and Isometric Responses,” ibid., 68 (1960), 165–180, written with R . Rubio; “The Accessory Motor Innervation of the Diaphragm,” ibid., 69 (1961), 19–25, written with J. Alanis and G. Pilar; “Relations Between Coronary Flow and Work of the Heart,” in American Journal of Physiology, 200 (1962), 243–246, written with J. Alanis, R. Rubio, and G. Pilar; “Some Phenomena Usually Associated with Spreading Depression,” in Acta physiologica latino-americana, 16 (1966), 141–179; “Slow Potential Changes in the Spinal Cord,” ibid., 16 (1966), 324–334, written with J. Garcia Ramos; “The Relations Between the Impedance and the emf Changes in the Cerebral Cortex,” ibid., 17 (1967), 76–87, written with J. Garcia Ramos and L. F. Nims; and “Slow Potential and Impedance Changes in the Medulla of the Cat,” ibid., 16 (1966), 212–219.