Neuroclown & Consciousness

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Aristotle had some interesting ideas on the function of the brain:
“For the brain, or in creatures without a brain that which corresponds to it, is of all parts of the body the coolest. Therefore, as moisture turned into vapour by the sun’s heat is, when it has ascended to the upper regions, cooled by the coldness of the latter, and becoming condensed, is carried downwards, and turned into water once more; just so the excrementitious evaporation, when carried up by the heat to the region of the brain, is condensed into a ’phlegm’ (which explains why catarrhs are seen to proceed from the head); while that evaporation which is nutrient and not unwholesome, becoming condensed, descends and cools the hot. The tenuity or narrowness of the veins about the brain itself contributes to its being kept cool, and to its not readily admitting the evaporation. This, then, is a sufficient explanation of the cooling which takes place, despite the fact that the evaporation is exceedingly hot.1”
Well, he may have gotten the part about vapours rising right, but the rest fairly wide of the mark. However, Aristotle does more than just claim that the brain cools the blood. Consider the preceding paragraph:
“For, as has been observed elsewhere, sleep comes on when the corporeal element [in the ’evaporation’] conveyed upwards by the hot, along the veins, to the head. But when that which has been thus carried up can no longer ascend, but is too great in quantity [to do so], it forces the hot back again and flows downwards. Hence it is that men sink down [as they do in sleep] when the heat which tends to keep them
erect (man alone, among animals, being naturally erect) is withdrawn; and this, when it befalls them, causes unconsciousness, and afterwards fantasy.”
So, to review, you get sleepy when the brain gets too hot, fall unconscious, then start to dream ...
Aristotle’s conjecture was straightened out shortly after by the pioneering anatomist Herophilus (335 B.C.E. – 280 B.C.E.) who correctly identified the brain as the source of the intellect. Aristotle, however, is still reasonably well regarded for some other small contributions to philosophy.

Phineas Gage

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Thomas Willis
Luigi Galvani
Franz Gall
Charles Bell


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