John Hughlings Jackson

“ Still it may be said that classification, on the principle of dissolution, if true, is of no value; that it is of no use making an orderly ascending series from progressive muscular atrophy to insanity—of no use showing that progressive muscular atrophy is reduction to a more automatic condition in a small corner on the lowest level, that hemiplegia is such reduction on a larger scale higher up, and that insanity is such a reduction on the topmost level, and on the largest scale—that even if this kind of work could be thoroughly well done it is not worth any one's while to do it. ”

“ Starting this time with health, the assertion is that each person's normal thought and conduct are, or signify, survivals of the fittest states of what we may call the topmost layer of his highest centers, the normal highest level of evolution. Now, suppose that from disease the normal highest level of evolution (the topmost layer) is rendered functionless. ”

“ Going a stage higher we come to hemiplegia, owing to destruction of part of a plexus in the mid-region of the brain. Choosing the commonest variety of hemiplegia, we say that there is loss of more or fewer of the most voluntary movements of one side of the body; we find that the arm, the more voluntary limb, suffers the more and longer; we find, too, that the most voluntary part of the face suffers more than the rest of the face. Here we must speak particularly of the lower level of evolution remaining ”

“ I know of no other basis on which cases of insanity, diseases of the highest centers, can be studied comparatively with non-mental diseases of the nervous system—diseases of lower centers.
I next speak of different depths of dissolution. The deeper the dissolution the shallower the level of evolution remaining. In hemiplegia, owing to lesion of the internal capsule, there are, according to the gravity of the lesion, three degrees or depths (of course the division into three degrees is arbitrary) . In the first degree there is some paralysis of the face, arm, and leg ”

“ While not asserting that the inability to say "No" when told is a failure in language, it is asserted that such inability with retention of power to use the word in reply illustrates dissolution, (e.) A patient who is speechless may be unable to put out his tongue when told to do so; that he knows what is wanted is sometimes shown by his putting his finger in his mouth to help out the organ. That the tongue is not paralyzed in the ordinary sense is easily proved. The patient swallows well, which he could not do if his tongue were as much paralyzed as "it pretends to be." ”

“ Yet, no one denies that each is a morbid affection of the central nervous system; this being granted, the rejoinder to those who insist on the extreme unlikeness is that the lesion in one is at the very bottom, in the other at the very top, of the central nervous system ”

“ After exposing the so-called motor region [5] of each half of the brain of a dog, they removed the motor region on one half, and then found that faradization of the "arm-center" on the half intact (left) produced universal convulsion; they found, too, that the spasm followed a particular order—that it affected the right arm (so to call it) , then the right leg, then the left leg, and then the left arm. [6] Here seems to be evidence that both sides of the body are represented in each half of the brain, and also that the two sides are differently represented in each half. ”

“ An adequate doctrine of localization has to account for such increase of paralysis in compound order on increasing gravity of lesions. In the third degree of, or rather beyond, hemiplegia there is universal immobility. In this degree the patient has lost consciousness, and this loss may be said to explain why he does not move the other or "second" side of his body. ”

“ At a stage when the muscles of the hand only are wasted, there is atrophy of the first or second dorsal anterior horn; the lower level of evolution is made up of the higher anterior horns for muscles of the arm. ”

“ On the other hand, we can conceive a center consisting of four sensory and four motor elements, in which, however, the junctions between the sensory and the motor elements are so imperfect that the nerve-currents meet with much resistance. ”

“ A man long subject to very limited epileptiform seizures may at length have seizures beginning in the same way, and becoming universal, but these are not epileptic seizures, they are only more severe epileptiform seizures. ”

“ Gesticulation, which is an emotional manifestation, must be distinguished from pantomime, which is part of intellectual language, (b.) The frequent persistence of "Yes" and "No," in the case of patients who are otherwise entirely speechless, is a fact of extreme significance. ”