Granit

1950 · réf. 68721 — 1950. J. Neurophysiol. 13. - September 1950 8° pp.351-372 17 Fig. orig. self wrappers. Offprint! Nobel Institute for Neurophysiology Karolinska Instituted Stockholm Sweden Received for publication December 5 1949 "The development that followed upon Sherrington's original discovery of the lengthening reaction 45 and P. Hoffmann's demonstration of the silent period in the electromyogram accompanying the knee jerk 28 may be well known but so much time has now elapsed since these problems were the subject of active experimentation that it is necessary in reopening the field to begin by surveying the ground in the light of recent research in order to show where we stand and why again reasonably some progress may be expected. Sherrington pointed out that the lengthening reaction in the quadriceps muscle was accompanied by Philippson's reflex of crossed extension as well as by ipsilateral flexion thereby giving autogenetic inhibition a functional status within the framework of reciprocal innervation. The silent period was held by Denny-Brown 9 on similar evidence to be but an expression of autogenetic inhibition. It was hypothetically localized to the annulo-spiral afferent system and shown to require a strong synchronous efferent volley set up by a tap on the tendon or by an electrical shock to the motor root. Hoff et al. 27 found a silent period in one extensor after excitation of another only when the former had discharged owing to facilitation." Ragnar Arthur Granit 1900-1991 was a Finnish-Swedish scientist who was awarded the Nobel Prize in Physiology or Medicine in 1967 along with Haldan Keffer Hartline and George Wald "for their discoveries concerning the primary physiological and chemical visual processes in the eye". unknown