Abstract
We have examined peripheral proprioceptive input during fall in man. The first 80 ms of unexpected free fall, both in a parachute harness and while seated, has been studied using the monosynaptic Hoffman (H) and Achilles tendon (T) reflexes. Facilitation of the H reflex begins about 30 to 40 ms after release, representing the onset of motor neurone facilitation before the electromyographic activity which begins about 80 ms after release. Earlier facilitation of the T reflex may represent spindle excitation due to change in muscle shape as suggested by Matthews and Whiteside (1960), but the T reflex inhibition described by these authors after 50 ms of seated fall is probably a purely mechanical phenomenon.
Full text
PDF
Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Delwaide P. J., Hugon M. H reflex depression by soleus sinusoidal stretching and facilitation by voluntary contraction. Experientia. 1969 Nov 15;25(11):1152–1153. doi: 10.1007/BF01900244. [DOI] [PubMed] [Google Scholar]
- GIBLIN D. R. SOMATOSENSORY EVOKED POTENTIALS IN HEALTHY SUBJECTS AND IN PATIENTS WITH LESIONS OF THE NERVOUS SYSTEM. Ann N Y Acad Sci. 1964 May 8;112:93–142. doi: 10.1111/j.1749-6632.1964.tb26744.x. [DOI] [PubMed] [Google Scholar]
- Greenwood R. J., Hopkins A. P. Proceedings: Muscle activity in falling man. J Physiol. 1974 Aug;241(1):26P–27P. [PubMed] [Google Scholar]
- Greenwood R., Hopkins A. Landing from an unexpected fall and a voluntary step. Brain. 1976 Jun;99(2):375–386. doi: 10.1093/brain/99.2.375. [DOI] [PubMed] [Google Scholar]
- Greenwood R., Hopkins A. Muscle responses during sudden falls in man. J Physiol. 1976 Jan;254(2):507–518. doi: 10.1113/jphysiol.1976.sp011242. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jones G. M., Watt D. G. Muscular control of landing from unexpected falls in man. J Physiol. 1971 Dec;219(3):729–737. doi: 10.1113/jphysiol.1971.sp009685. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kots Ia M. O supraspinal'nom upravlenii segmentarnymi tsentrami myshts-antagonistov u cheloveka. I. Reflektornaia vozbudimost' motoneironov myshts-antagonistov v period organizatsii proizvol'nogo. Biofizika. 1969 Jan-Feb;14(1):167–172. [PubMed] [Google Scholar]
- MAGLADERY J. W., PORTER W. E., PARK A. M., TEASDALL R. D. Electrophysiological studies of nerve and reflex activity in normal man. IV. The two-neurone reflex and identification of certain action potentials from spinal roots and cord. Bull Johns Hopkins Hosp. 1951 Jun;88(6):499–519. [PubMed] [Google Scholar]
- Pagni C. A., Ettorre G., Infuso L., Marossero F. [EMG responses to capsular stimulation in the human]. Experientia. 1964 Dec 15;20(12):691–692. doi: 10.1007/BF02145277. [DOI] [PubMed] [Google Scholar]
- Taborikova H., Provini L., Decandia M. Evidence that muscle stretch long-loop reflexes from higher centres. Brain Res. 1966 Aug;2(2):192–194. doi: 10.1016/0006-8993(66)90026-6. [DOI] [PubMed] [Google Scholar]