English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Open

Presents the pdf analysis as premium feature

PDF Analysis

Insights

Presents the summarisation as premium feature

Summarisation

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

movements of paralysed limbs and other parts of the body is a well known thing in cases of hemiplegia. When, for instance, the leg on the unaffected side is voluntarily moved, it often happens that the paralysed leg moves with it, and when a deep yawn occurs the paralysed arm is frequently drawn across the chest with great force. While the mechanism by which these movements are probably produced has been carefully studied the physiological reasons for their existence do not appear to have received so much attention, and, after briefly referring to their mechanism, I shall endeavour to show that, at any rate in some cases, these movements have a definite history in evolution, and that they were once useful for the ordinary purposes of life. In the case of a complete hemiplegia due, say, to destruction of the internal capsule, it is instructive first of all to enquire what changes have resulted from the lesion in order to allow the associated movements to take place, or, to put the question in another way, to enquire what influences are present in health to prevent them taking place. The answer to this question is to be found by a consideration of the functions of the pyramidal tracts which are destroyed in such a lesion as that suggested above. These functions are in the main twofold; the fibres conduct (1) impulses which give rise to voluntary movements, and (2) impulses which exercise a constant inhibitory effect on the lower centres. When these fibres are destroyed there is loss of voluntary power as seen by the paralytic symptoms, and loss of inhibition as seen by the rigidity and increased reflex irritability. It is doubtless this loss of inhibition which allows associated movements, for otherwise there seems no reason why those which occur in hemiplegia should not also occur in health. With regard to inhibition in the case of the respiratory centre, and the results of cutting it off in hemiplegia, Dr. Hughlings Jackson's observations may be referred to here(Lancet, February 23, 1895). In hemiplegia, Dr. Jackson found that during ordinary or automatic respiration the amplitude of the superior intercostal movements was greater on the paralysed than on the sound side, while in voluntary respiratory movements the movements were greater on the sound side. Pierce Clark (Am.) has recently confirmed this observation and gives the following explanation. "In destructive lesions of the internal …

ASSOCIATED MOVEMENTS IN HEMIPLEGIA: THEIR ORIGIN AND PHYSIOLOGICAL SIGNIFICANCE.