Abstract
LONDON. Royal Society, June 11.—R. Magnus: Animal posture (Croonian Lecture). Postural centres in brain-stem compound the body musculature to com bined action. Postural stimuli arise from many different sense organs. Change in position of one part of the body is followed by postural (usually harmonious) changes in other parts. Postures are adapted to environment by combined action of dis tance receptors and attitudinal reflexes. The righting function, absent in decerebrate, is present in midbrain animals. Righting reflexes evoked from labyrinths, exteroceptors, and proprioceptors, bring head and body into normal position. Optical righting reflexes are present in higher mammals only. Paralysis of one righting apparatus is usually compensated by other righting reflexes. Centres for righting are arranged subcortically. The resting position of the eyes changes with different positions of head, and is con trolled by postural reflexes. In animals with lateral eyes (rabbits) the visual world remains fixed in spite of head movements. This is accomplished by the com bined action of otolithic and neck reflexes. Motor reflexes from the semicircular canals initiate these static reactions of the eyes. Centres for all these reflexes are arranged in three groups. The red nucleus is the centre for two of the righting reflexes. Laby rinthine reactions have greater importance in lower mammals. Postural function of other parts of brain is largely unknown.
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Societies and Academies. Nature 115, 965–967 (1925). https://doi.org/10.1038/115965b0
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DOI: https://doi.org/10.1038/115965b0