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THE INTERNATIONAL COMMISSION ON BRAIN RESEARCH.
The idea of appointing a special commission to advise the International Association of Academies as to the means best calculated to advance and coördinate research work on the brain originated, so far as I am aware, with the late Professor His. He formulated a somewhat ambitious scheme, the main idea of which was the foundation in each country of a central institute to, in a sense, control the research work being done in that particular country and to serve as a means of communication with similar institutes in other countries. The function of these institutes was to receive material for research, sent by people who did not particularly want it, and to distribute it to workers to whom it would prove of special value ; to receive and store specimens, photographs and other records of research, so that any worker might have the opportunity of examining the actual material upon which published memoirs were based.
The author of the scheme hoped that by means of such institutes more uniformity might be introduced in the methods of research, and in the presentment of results; that the data upon which investigations were founded might be rendered more accessible than heretofore and so a common source of disagreement among workers might be removed; and especially that valuable material might be directed into those channels where the best use might be made of it.
To discuss this proposed scheme a special commission of thirty-five members representing fourteen nationalities was appointed. It was subdivided into seven sub-sections of five members each to consider the scheme from the standpoints of (1) Human Anatomy and Anthropology, (2) Comparative Anatomy, (3) Histology, (4) Embryology, (5) Physiology, (6) Pathology and (7) Clinical Medicine.
The Commission met in London in the last week of May without its leader and prime mover, without the one man whose quiet persistency could have brought any measure of success in the realization of his scheme: Professor His died in Leipzig three weeks before the meeting.
Under these depressing circumstances only about twenty of the remaining thirty-four members of the Commission were able to attend the meeting, over which Professor WALDEYER presided. The subdivision into special subsections was abandoned and a general discussion took place as to the feasibility of establishing such institutes as the late Professor His had suggested. In the public discussion the chief difficulty brought forward against the realization of the scheme was financialthe need for funds to establish and maintain the institutes ; but in private conversation with the members there seemed to be a general concensus of opinion that the scheme was too utopian; that it was hardly likely that any considerable body of men would be so self-denying as to present their material to an institute for distribution and that the possibility of accomplishing the other objects aimed at in the general scheme seemed to be very slight. However, the members present agreed to strive to make the existing institutions in which each of them was working serve as far as possible the function of such a central institute as had been outlined in the general scheme.
This platonic resolution was the only result of the general meeting of the Commission.
At the general meeting Professor EDINGER remarked that this exceptional meeting of neurologists afforded an excellent opportunity to discuss certain problems of general interest, and he proposed that a special meeting be held to discuss the primary subdivision of the vertebrate cerebral hemisphere. At the special meeting, which was presided over by Professor J. N. LANGLEY, Professor EDINGER explained that his chief reason for calling the meeting was to discuss the possibility of devising some primary subdivision of the lowlier vertebrate types of cerebral hemisphere such as I had proposed for the Mammalia. I was requested to explain to the meeting the nature of my subdivision of the mammalian hemisphere and especially the significance of the neopallium. In the discussion, which was carried on chiefly by the chairman, Professors Retzius, EDINGER and the writer, it was agreed that it was not possible at present to suggest any satisfactory mode of subdivision which
could be applied to all vertebrates, because the differentiation of structure in the higher groups rendered useless the subdivision which would apply to the lowlier groups. It was therefore decided to submit the question to further investigation and Professor Edinger invited me to prepare a report proposing a subdivision, which might be submitted to all those interested in the problem, whether members of the Commission or not, for criticism and suggestions.
The other question brought forward for discussion was the possibility of describing cerebral sulci from their relationship to areas of known physiological significance. I explained the definite relationship which the calcarine sulcus, the sulcus lunatus ("Affenspalte") and the superior and inferior occipital sulci present to the visual cortex. The essential part of the suprasylvian sulcus is a superior limiting furrow of the auditory cortex. The central sulcus in the Primates is a posterior limiting sulcus of the excitable or motor area, whereas the crucial sulcus of the Carnivora is an anterior sulcus of the motor cortex. In time it will probably be possible to describe all the important furrows of the hemisphere in terms of their relationship to certain definite cortical areas and so to correlate the data of morphology and physiology. The excellent researches of Dr. A. W. CAMPBELL of Liverpool and the well-known work of Professor FLECHSIG are rapidly preparing the way for such an advance.
In the discussion of this matter, in which Professors HENSCHEN, RETZIUS, VON MONAKOW, EDINGER and LANGLEY took part, it was agreed that it was too early to adopt the proposed method of describing sulci.
At other informal meetings various members of the Commission gave demonstrations. Professor RAMÓN Y CAJAL showed extraordinary specimens of neurofibrillae in ganglion cells stained by his new method and Professor HENSCHEN showed many sections of the calcarine region exhibiting various forms of degeneration in the visual area. The Commission is to meet again three years hence.
G, ELLIOT SMITH.
Goldstein, Kurt. Kritische und experimentelle Beiträge zur Frage nach dem
Einfluss des Nervensystems auf die embryonale Entwicklung und die Regeneration. Three plates and two text-figures. Arch. f. Entwkmech.,
1904, 18, 57-110.
SCHAPER's experiment which showed motility in a frog larva in which he had destroyed the brain and found the spinal cord in a state of disorganization, left a certain desire for more evidence. WOLFF failed to obtain the same decisive result, and Moskowski actually considered the claim refuted. GOLDSTEIN, a pupil of SCHAPER, now supplements the first description by a drawing which is more convincing than SCHAPER's original one, and he adds new experimental material, which shows WOLFF's error and firmly establishes very important data in harmony with SCHAPER's observations.
Wolff divided frog larvae of less than 5 mm. so that the dorsal part contained the entire neural tube, and failed to corroborate SCHAPER. GOLDSTEIN succeeded in keeping both parts alive for five days, through the use of LOCKE's solution, and he showed that they recover motility in two days. Hence, spontaneous and reflex motility in an early embryonic period does not depend on the existence of nerve conduction of a central organ. Moreover, the ventral piece showed further development; notwithstanding the elimination of the neural tube it reached the size corresponding to a larva of about 6.5 to 7.0 mm. Against these facts any arguments based on laws of regenerative processes have absolutely no weight, since we deal here merely with a primary condition of development.
GOLDSTEIN next turns against certain views of NEUMANN. The latter had concluded that at least for a start in the development of muscles, nervous centers were necessary; that, once started, they would develop independently from the central organ, and, in post-embryonic life the trophic center of cord and brain would again put them into a dependent position. The first point is contradicted by various facts. BARDEEN found that muscle differentiation began before the nerves grew forth from the tube. Also HARRISON demonstrated an inde
pendent development of muscle with fibrils, striation and sarcolemma after excision of the spinal cord and ganglia in larvae of 2.9 and 3.7 mm. NUSSBAUM, too, admits an independent development of embryonic muscles up to a certain degree—all agree with GOLDSTEIN's result that NEUMANN's first claim is incorrect. His second claim, made in order to explain the persistence of muscles in the amyelic monsters, would not be conclusive on his own assumptions. The muscles need not have degenerated within the short time between the lesion (3d or 4th month) and birth (usually in the 6th or 7th month). In WEBERALESSANDRINI monsters the lesion must have occurred at 2-3 months and the animal reached full term ; the muscles were, therefore, degenerated and mere fat layers and tendons. LEONOWA also found the muscles of her case of amyelia extraordinarily fatty. (It seems, moreover, that the condition of the motor nerves in these monsters is not satisfactorially ascertained, but should be of great importance in view of BETHe's claims). HERBST's attempt to attribute a trophic control over muscles to the spinal ganglia is refuted. Taking all the facts together, GOLDSTEIN comes to the conclusion that the central nervous system during a certain early period of development has no demonstrable morphogenetic influence on the developing organism.
The second part of GOLDSTEIN's article furnishes evidence showing that this same rule holds for regeneration. Regeneration need not follow the rules of development. It also depends largely on the age of the animal or embryo. The results in invertebrates are contradictory; those on vertebrates (BARFURTH), probably favorable to the theory of independence from the central nervous system. In adult Tritons WOLFF thought he had proved the necessity of a nervous influence. He obtained regeneration of a leg after removal of the cord, but with intactness of the ganglia; when the operation was done while regeneration had begun it was arrested in all but six cases. In an experiment of SCHAPER on a Triton larva of 30 mm., an tremity was regenerated after destruction of the cord, and although there was complete absence of sensibility and motility. What nerves there were, came “largely” from the spinal ganglia ; the muscles were normal ; even a piece of i mm. of spinal cord had reformed at the posterior end of the cut of the cord.
The conclusion is: In the stage of organ formation (Roux) the normal development and regeneration take place quite independent of the nervous central system. In the stage of functional development there is, however, a decided influence from the central organ.