The special communications of the motive segments of the crus of the brain with the intellect : also, the separate parts of the brain producing the three voluntary powers of the muscles / by Joseph Swan.

  • Swan, Joseph, 1791-1874.
Date:
1862
Catalogue details

Licence: Public Domain Mark

Credit: The special communications of the motive segments of the crus of the brain with the intellect : also, the separate parts of the brain producing the three voluntary powers of the muscles / by Joseph Swan. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    the perceptive faculties. They may also convey power from the intellect to the nerves and organs, and prepare them for their required activity, by imparting the tonic quality when their attention is required. Although the convolutions of the intercedent region are connected with cerebral and spinal nerves which have different functions, the whole receive the same high sensorial power. But it may be presumed that the anterior convolutions become more energetic from the greater thickness of the superincumbent grey matter of the striated body connected with them. Their high sensorial qualities prepare them for acting with the intellect, when it is specially required in directing par- ticular muscles for adding mental qualities to the phy- sical—as for speaking or singing, for writing or drawing, or for animating the features, and promoting particular attitudes of the body. The muscles are also concerned in the consummation of the sensitive functions. The influence, therefore, of the intellect communicated through the intercedent tracts to the voluntary crossing ones, only resembles a more complex act of the will for directing the muscles to produce speech instead of vague sounds, and writing or other accomplishments, instead of ordinary motions. In animals there are only two convolutions anterior to that of the true visual tract, and one of them invariably descends to the part of the cms giving origin to the