Sherrington, to whom we owe much of our knowledge of nerve activity, obtained his medical degree in 1885, then devoted himself to physiological research at Cambridge. His first major experiments dealt with the interaction of spinal reflex patterns, and the results were described in The Integrative Action of the Nervous System, published in 1906. According to Boring (1950), this book stimulated more interest in physiological psychology than any previously published work.Sherrington made significant contributions to the study of reflexes, and was the first to show the importance of proprioceptive reflexes in posture. In the course of his investigations of the nervous system, he introduced the concept of the synapse as the place where neurons interact. He also demonstrated many of the specific functions of the synapse, such as facilitation and inhibition. He showed, for example, that stimuli too weak to produce a response by themselves may add to each other, or “summate,” at the synapse, and sometimes gather enough strength to facilitate a response. On the other hand,stimuli which are strong enough to produce a reflex response by themselvesmay be inhibited at the synapse by impulses from other nerve fibers.Sherrington also demonstrated the effects of drugs and fatigue on the nervous system. He found that nerve tissue which contains synapses is able to conduct for only a brief period of time, while tissue that does not contain synapses is unaffected by fatigue. Similarly, he discovered that certain drugs produce a blockage of impulses in regions where synapses are present, but no such blockage occurs in regions where there are no synapses. He also showed the great importance of the synapse not only in lower sensory and reflex activities, but in the higher mental processes.Sherrington’s discoveries have had widespread application in the fields of neurology and neurosurgery. But they have had an equally great effect on psychology, since they have contributed much to our understanding of the neural basis of behavior. His work was widely recognized during his lifetime, and he served as president of the Royal Society from 1920 to 1925. He was one of the few scientists to receive the Order of Merit, and in 1932 was awarded the Nobel Prize for pioneer work on neural activity, an honor he shared with E. D. Adrian. His last published work, written at the age of eighty- three, was Man on His Nature, a book which dealt with the philosophical question of the relationship between mind and matter as seen from the standpoint of a physiologist.