Biographies de neurologues
Nouvelle Iconographie de La Salpêtrière
 L'histoire des neurosciences à La Pitié et à La Salpêtrière J Poirier
The history of neurosciences at La Pitié and La Salpêtrière J Poirier 

mise à jour du
 15février 2009
Blanchard & Lea
Principles of human physiology
William B Carpenter
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page 115-116
104. It may not improbably be in this manner, that a number of those so-called "spiritual" phenomena are produced, in which "subjective" Sensations of various kinds are distinctly felt by 'persons who are not only wide awake, but are entirely ttustworthy on all other matters, though self-deceived as to the reality of the objective sources of their sensation. Having resigned the exercise of their Common Sense quoad this particular set of beliefs, and having allowed them to gain a mastery over their ordinary course of thought, there is nothing wonderful in the automatic and unconscious evolution of results corresponding to these beliefs ; which results, impressing themselves on the Sensorium, are felt as true sensations. And just as Sir John ilersôhel truly saw as geometrical forms the unconscious constructions of his own Cerebrum, so, it seems probable, may the "spiritualist" truly see the strange things he describes as actual occurrences, although they have no foundation whatever in fact ( 147).
105 Another consideration which strongly indicates that the action of Cerebral changes on the Muscular apparatus is exerted through the instrumentality of the Sensorial apparatus, is the identity of the effects often produced by ideas, with those produced by sights, sounds, or other Sensations which call forth respondent motions. Thus in a person predisposed to yawn, the verbal suggestion of the notion of yawning is almost as provocative of the act, as the sight or sound of a yawn in another. So, again, a "ticklish" person is affected in the same way by the mental state suggested by the pointing of a finger., as by the actual contact. And so in a hydrophobic patient, the same paroxysm is excited by the idea of water suggested by words or 'pictures, as by the actual sight or sound of it. So far, then, from being a source of additional complexity, the doctrine of the singleness of the Sensorial nerve-centre, through the instrumentality of which we, become conscious alike of Sense-impressions and. of Cerebral changes, and from which the Motorimpulses to respondent action immédiately proceed, will be found (the writer believes) to lead a real simplification in the interpretation of a large class of phenomena occupying the border ground between physical and psychical action.
106 That the different portions of the Cerebrum should have different parts to perform in that wonderful series of operations by which the Brain as a whole becomes the instrument of the Mind, can scarcely be regarded as in itself improbable. But ro determination of this kind can have the least scientific value, that is not based on the facts of Comparative Anatomy and Embryonic Development. In ascending the Vertebrate series, we find that this organ not only increases in relative size, and becomes more complex in general structure, but undergoes progressive additions which can be definea with considerable precision. For the Cerebrum of Oviparous Vertebrata is not a miniature representative of the entire Cerebrum of Man, but corresponds only with its "anterior lobe;" and is entirely deficient in that great transverse commissure, the corpus callosum ( 89), the first appearance of which, in the Placental Mammals, constitutes "the greatest and most sudden modification exhibited by the brain in the whole Vertebrated series" (Huxley). It is among the smooth-brained Rodentia that we meet with the first distinct indication of a "middle lobe," marked off from the anterior by the "fissure of Sylvius;" this lobe attains a considèrably greater development in the Carn'ivora; but even in the Lemurs it still forms the hindermost portion of the Cerebrum. The "posterior lobe" makes its first appearance in Monkeys; and is distinctly present in the anthropoid Apes. The evolution of the Human Cerebrum follows the same course. For in the first phase of its development which presents itself during the second and third months, there is no indication of any but the anterior lobes ; in the second, which lasts from the latter part of the third month to the beginning of the fifth, the middle lobes make their appearance ; and it is not until the latter.........