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A. Earl Walker, Jerry J. Kollros and Theodore J. Case

.) Paris: A. Delahaye , 1873, 167 pp. 10. Goodwin , C. W. A differential amplifier for resting and action potentials of biological systems. Yale J. Biol. Med. , 1941 , 14 : 101 – 106 . Goodwin , C. W. A differential amplifier for resting and action potentials of biological systems. Yale J. Biol. Med. , 1941, 14: 101–106. 11. Gurdjian , E. S. , and Webster , J. E. Experimental and clinical observations in the mechanism of head injury. Res. Publ. Assn. nerv. ment. Dis. , 1943 , 24 . (In press

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Electrospinogram (ESG)

Spinal Cord Action Potentials Recorded from a Paraplegic Patient

James L. Pool

S pinal cord action potentials were recorded from below the level of proven complete traumatic transection in a paraplegic patient without exposing the cord. A three-channel ink-writing amplifier was used, ordinarily employed for routine electroencephalography. Fine insulated unipolar and bipolar needle electrodes were used to obtain readings from the isolated segments of the transected cord. The test was carried out in the hope of securing beneficial information regarding the mechanism of the patient's distressing mass flexor spasms. As far as can be

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Edgar A. Kahn

day the spasticity in the legs was less marked. She was discharged the 12th postoperative day, greatly improved. Examination 5 months postoperative revealed complete recovery. Discussion . It is my opinion that similar cases are not rare and the following is an attempt to explain how pressure exerted anterior to the cord could result in a syndrome of lateral sclerosis. * Gasser and Erlanger, 3 in studying action potential waves in peripheral nerves, classified nerve fibers into three groups, A, B, and C, according to strength of stimulus necessary to produce

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Faulty Sensory Localization in Nerve Regeneration

An Index of Functional Recovery Following Suture

George L. Hawkins

spot thus results in impulses conducted over several separate axons, and a single axon can be stimulated from several sensory spots. Tower's theory of sensory localization based on nerve fiber distribution in the cornea and on action potentials from “few fiber” preparations of the long ciliary nerves is accepted as the mechanism of tactile localization. 23 Briefly, it holds that a one-to-one relationship between cutaneous spot and cortex does not exist, but instead the central nervous system assigns a locus to a stimulus by integration of the repetitive firings in

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I. M. Tarlov, W. Boernstein and Doreen Berman

calibre than those centrally. Gros-Bielschowski technique for axis cylinders, ×23. C, Osmic acid preparation of segment of sciatic nerve 20 cm. from suture site. Nerve was removed at time of sacrifice of dog 369 days after suture; ×230. III. Reconstitution of Numbers and Diameters of Medullated Nerve Fibers after Suture . It has been shown by various investigators 5 that the different groups of fibers representing various diameters and degrees of medullation, produce the different components of the conducted action potential of the peripheral nerve and

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R. F. Heimburger, L. W. Freeman and N. J. Wilde

. , 1932, 2: 683–685. 6. Cordier , P. Sur l'innervation de l'utérus. C. R. Soc. Biol., Paris , 1921 , 84 : 898 – 900 . Cordier , P. Sur l'innervation de l'utérus. C. R. Soc. Biol., Paris , 1921, 84: 898–900. 7. Evans , J. P. Observations on the nerves of supply to the bladder and urethra of the cat, with a study of their action potentials. J. Physiol. , 1936 , 86 : 396 – 414 . Evans , J. P. Observations on the nerves of supply to the bladder and urethra of the cat, with a study

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Cell Stations in the Upper Sympathetic Chain

Evidence that Functional Regeneration of Sympathetic Nerves in Man Occurs only in Postganglionic Neurones

Olan R. Hyndman, Julius Wolkin and M. W. Van Allen

.5 cm. proximal to the superior cervical ganglion. He followed the histological evidence of regeneration as well as the physiological evidence. He concluded that preganglionic fibers regenerated and resumed their synaptic connections with the postganglionic cell bodies in the superior cervical ganglion. Concomitant with this the cells of the superior cervical ganglion and their fibers appeared to resume function. Function was determined by demonstrating action potentials with the cathode-ray oscillograph. Gibson 2 quoted others who had done essentially the same work

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Studies on the Sacral Reflex Arc in Paraplegia

I. Response of the Bladder to Surgical Elimination of Sacral Nerve Impulses by Rhizotomy

Arnold M. Meirowsky, C. David Scheibert and Thomas R. Hinchey

: 367 – 445 . Elliott , T. R. The innervation of the bladder and urethra. J. Physiol. , 1907, 35: 367–445. 8. Evans , J. P. Observations on the nerves of supply to the bladder and urethra of the cat, with a study of their action potentials. J. Physiol. , 1936 , 86 : 396 – 414 . Evans , J. P. Observations on the nerves of supply to the bladder and urethra of the cat, with a study of their action potentials. J. Physiol. , 1936, 86: 396–414. 9. Freeman , L. W. , and Heimburger , R. F. The surgical

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Paul F. A. Hoefer and Sidney M. Cohen

N ormal striated muscle at rest shows no sign of electrical activity. 6, 10 Muscle action potentials occur as the result of all forms of physiological or pathological innervation. This is produced by impulses transmitted to the lower motor neurone from reflex fibers or by way of internuncial neurones from descending motor tracts. 7, 11, 12, 13 Under special conditions impulses may arise in the lower motor neurone itself. 4 When pathological stimuli arise at segmental levels, as the result of irritative action on afferent, central or efferent structures, it

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Eric Kugelberg and Ingemar Petersén

required voluntarily to contract the muscles to the maximum. In patients with incapacitating pain the greatest care was taken to ascertain whether a true paresis existed, or whether there was merely a functional reduction of strength due to pain. Here the electromyogram has been a valuable control, because the frequency of the individual action potentials is a good index of the degree of contraction. In electromyography the current method of evaluation has been followed. 6 The muscles of both sides have always been compared, and only those with clear neurogenic