He also attended Hartford public schools. In West Hartford High School he had been a star athlete in many sports, but he did well enough to acquire a scholarship to Oberlin College, in Ohio. At school, Sperry's most important passion, besides 17th century English poetry, appears to have been sports, as in high school. He had been captain of the basketball team, and in addition, he participate in varsity baseball, soccer, and track.
Then he went into the University of Chicago, where he worked to get his Ph.D. in zoology beneath Paul Weiss, among the most influential biologists of the moment.
His lectures neurospecificity (outlined below) were brilliant, and he had been offered the place. He also joined the Caltech faculty in 1954 and stayed there for the remainder of his life.
Sperry's first important scientific function -- one that occupied him for more than a decade was to disprove a broadly accepted concept that was improved by his professor in the University of Chicago, Paul Weiss. In accordance with the concept, the huge neural system that joins the nerves and muscles to the mind originates as an undifferentiated and unspecified net of randomly linked nerve pathways that is later altered, under the sway of expertise and learning, to the highly coordinated, purposeful system that's really found in animals. Plasticity and interchangeability of purpose were the crucial notions. This concept didn't come from the blue, clearly, but was based on careful experimental work which Weiss had completed, but misinterpreted.
In a set of experiments which are very famous, Sperry revealed the true condition of affairs is just the contrary of the envisioned in Weiss' concept. Rather than being composed of interchangeable components, the circuits of the brain are mainly hardwired, in the sense that every nerve cell is labeled with its chemical identification early in embryonic development; after this occurs, the purpose of the cell is fixed and isn't modifiable thereafter.
The experiments that led to this revolutionary decision entailed surgical procedures on many different creatures from fish and salamanders to monkeys. Sperry revealed that if neural links were calibrated -- for instance, by redirecting to another side of the creature the sensory nerves which innervate the left foot of a rat -- improper answers led that couldn't be unlearned. In cases like this, stimulation of the ideal foot led to the rat to move its left foot, and no quantity of expertise or retraining could alter this reaction.
In experiments with fish, frogs, and salamanders (selected since they have excellent forces of regeneration), Sperry revealed that human nerve pathways (which are different cells) act like each is different from each other, and these chemical differences are matched in the mind. The outcome is that in a creature whose optic nerves are improved then permitted to regenerate, the thousands of individual fibers which constitute each optic nerve develop back in the mind and there make the very same connections they had earlier. The creature is then able to determine as though the nerves hadn't been severed. Evidence that no elastic reorganization of these neural tissues is associated with regeneration consisted of demonstrating that when an eye whose optic nerve is severed can also be rotated in its socket, the world seen from the eye following regeneration remains upside down and backward. Additionally, as in the instance of the rat together with the nerves that are crossed, no amount of retraining makes it view properly: the creature constantly strikes to the left as it sees a pig on its own right.
Read more about Roger Wolcott Sperry
Comments