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convolutions of the great longitudinal fissure, completely dividing the anterior cerebral lobes down to the corpus collosum; but in 90 per cent. of chronic insane, this membrane is more or less destroyed, and the superior frontal and marginal convolutions of the right and left frontal lobes are not only in contact, but are so fused together, that they can not be separated without destroying the convolutions.

The foregoing is a hasty sketch of our investigation in this special field of research.

DISCUSSION.

Dr. Fields-Mr. President, I have just one word to say. I have believed for years that insanity is a disease of the brain and not of the mind. There can be no disease of the mind. Really insanity is either organically or functionally a disease of the brain. These cases, I think, demonstrate the fact. A man that has a healthy brain will never become insane, no matter how hard he studies. The more he exercises the brain the saner he is; a great student never became insane. The brain gets stronger by exercise like the blacksmith's arm; no matter how much he studies it does the brain good. Insanity occurs more with people who never exercise the brain. I think the paper clearly demonstrates the fact that insanity is a disease of the brain, either organic or functional.

Dr. Fletcher—I will just state, Mr. President, for fear some reporter. is present, that in every instance in these examinations the consent of the friends has been given that such autopsy should be made. You, as physicians, know that it can be done without marring the external appearance a particle. In a few instances where persons were unclaimed entirely, consent has not been had, but with all who had friends consent has been had. I am happy to say that there is a growing feeling towards making a proper study of these cases of insanity. It is not now as it was twenty years ago in this respect.

CEREBRAL LOCALIZATION.

BY F. A. MORRISON, M. D., INDIANAPOLIS.

The subject of cerebral localization has in view of the recent numerous successful surgical operations upon the brain assumed great importance in medical literature.

Many are probably deterred from an attempt at its study by the seeming complexity of the arrangement of the cerebral convolutions and the limitations, supposed or real, of certain functions to an exceedingly circumscribed portion of different convolutions. Nor does it appear that investigators have attempted to simplify matters, but have continued to multiply, often by artificial means, the naturally numerous divisions of the brain surface. Neither has the relations of the brain structure to the skull in life received the attention merited by its importance. The practical surgeon is continually looking out for "land marks" upon which to base his operations, and the minute divisions and questions of pathology are to him of secondary importance.

In order to gain an adequate knowledge of the anatomy of the brain for every-day work it is only necessary to fix in the mind the situation of two fissures, viz.: the fissure of Sylvius and the fissure of Rolando.

The situation and relations of these to the skull being once remembered the mapping out with considerable exactness the various motor regions of the brain is accomplished with great facility.

Such complicated directions (which apply in the main after all to the dead body) are given for determining these points by a series of lines drawn at intervals, parallel or at right angles, to a base line, termed the alveolo-condyloid plane of Broca, that they

are of little, if any, utility in the living body. Even the advocates
of this plan of measurement must admit that, as the course of the
convolutions is not exactly the same in any two brains, nor, indeed,
upon the two sides of the same brain, that their plea for extreme accu-
racy must fall to the ground. It would appear more rational to
presume that the convolutions, themselves anatomical divisions,
must bear a certain relationship to other markings upon the skull,
and that anatomy, rather than the compass and rule, should pro-
vide the means of diagnosis. The middle portion of the Sylvian
fissure is to be found just beneath the squamous suture at its
highest part, from which its course can be followed forward to the
point of bifurcation into the vertical and horizontal links at a point
one-third of an inch below the juncture of the coronal suture with
the great wing of the sphenoid bone. All these parts can, with
ordinary care, be detected in the living body. The fissure of
Rolando follows the course of a line drawn from that portion of
the squamous suture just above the external auditory meatus to a
point midway between the junction of the coronal and sagittal, and
the sagittal and lambdoidal sutures. These anatomical markings are
likewise easily susceptible of demonstration. Around these two
fissures, especially the latter, are grouped the most important motor
centers hitherto demonstrated in the cerebral cortex.
With con-
siderable exactness, the fissure of Rolando marks the division of the
surface of the brain into an anterior or motor and a posterior or
sensory region- the latter presiding over both general and special
sensation. All that portion of the cerebral substance lying imme-
diately in front and to the extent of one convolution behind
Rolando's fissure has been subjected to a large number of experi-
ments and settled upon as the seat of motor impressions of various
kinds. It is true that these deductions have at times been attacked
with more or less show of success, but it is nevertheless true, so far
as I know, that corresponding regions on both sides of the brain
are never destroyed without a total destruction of the functions
attributed to that part. Ferrier has shown that in the monkey, de-
struction of one visual center seems in some instances to produce
only a temporary effect, while destruction of both occasion imme-
diate and permanent blindness.

Two cases coming under my observation are of interest as af

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fording evidence of the existence in man of centers corresponding to those in the lower animals. In the year 1885, owing to a contracted pelvis in the mother, I was compelled to deliver with forceps a large-sized child. The delivery was accomplished with considerable difficulty, and possibly from faulty application of the instruments an abrupt depression was made by the extremity of the blade in the left parietal region. This depression, situated just in front of the upper extremity of the fissure of Rolando, was in the region asserted to be the center for certain complex movements of the muscles of the opposite leg. The right foot was in the position of talipes varus. An examination of the affected member convinced me that the condition was one of paralysis of the muscles on the outer side of the foot rather than contraction of those along the inner. Coincident with the restoration of the depression in the skull to the general level, which occurred in a few days, there was improvement and ultimately complete return of the foot to its proper position. This may have been a simple coincidence, but it was sufficient to arrest my attention and cause a more critical examination of the case, and the conclusion was forced upon me that there was an intimate connection between the deformity and the brain injury. Shortly afterwards the following case came under observation: A lady, aged forty-six, was suddenly taken with dizziness followed by vomiting and complete unconsciousness. After remaining in this condition a short time she revived, and it was then discovered that she was completely aphasic and that there was slight weakness of the muscles of the right arm. I think that the majority will agree with me that the diagnosis of effusion into or about the island of Reil on the left side was correct. She continued in the same condition of aphasia for upwards of three months, when, upon rising from her chair, she fell and became almost immediately unconscious. The head was drawn to the right side and the eyes, with pupils largely dilated, turned in the same direction. After the lapse of eight hours the head and eyes regained their normal positions, and the pupils became greatly contracted, in which condition death occurred. This case it seems to me afforded throughout its entire course signal confirmation of the localization theory. The two successive attacks, to my mind, indicated by their symptoms the existence of two centers in close

relationship, the one devoted to speech, the other presiding over the movements mentioned above as having occurred. By a reference to the works of investigators in this branch of physiology it will be seen that there is a circumscribed portion of the brain, comprising part of the superior and middle frontal convolutions, and almost touching the island of Reil, irritation of which produces the identical symptoms detailed in the second attack. In this case during the second attack irritation first occurred, then, by a continuance of the hemorrhage, destruction of the part followed, leading to abatement of the symptoms.

Many cases have been cited in opposition. Chief among these is what is known as the "American crow-bar case," the details of which are familiar to all students of physiology. The instrument here passed through the extreme anterior portion, or what has been denominated the "pre-frontal region," considerably in front of any of the portions of the brain devoted to sensation or motion so far as known. Nor is the general belief that the patient suffered no mental injury well grounded, since it is distinctly declared thať "he became irritable and cross, and his employers were ultimately compelled to remove him from his position as foreman." The writer is personally acquainted with an instance in which a pistol ball traversed the "pre-frontal region" without any marked effect upon the mental or physical vigor of the subject.

While a student of medicine an example came under my observation which is a fair sample of almost all the cases quoted in contradiction. A young man, aged about twenty-six years, was struck, during a brawl, by a beer glass, on the right side of the head. He fell unconscious, but soon rallied and walked away. For the period of a week he lay around the house, not being able to work, but presenting no marked symptoms of any kind. At the end of this time, as the result of a debauch, he was suddenly taken with severe cerebral symptoms and speedily became comatose. His physician, Dr. H. F. Barnes, of this city, rightly concluding that there was a fracture of the skull, and probably abscess of the brain, trephined at the seat of injury. The skull was found broken and the depressed portions removed. Notwithstanding this the patient died in a few hours. A post-mortem showed extreme inflammatory softening of all those portions of the

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