The Cerebellum and Its Wrapping Meninge: Developmental Interplay between Two Major Structures

2017 ◽  
Vol 48 (05) ◽  
pp. 329-339 ◽  
Author(s):  
Martin Catala

AbstractMeninges have long been considered as a protective and supportive tissue for the central nervous system. Nevertheless, new developmental roles are now attributed to them. The meninges that surround the cerebellum come from the cephalic mesoderm. They are essential for the cerebellum to develop normally. They induce and maintain the basal lamina and glia limitans. In the absence of these structures, the external granular cells of the cerebellum migrate aberrantly and penetrate the subarachnoid space. The molecules involved in the recognition between the cerebellar primordium and the basal lamina belong to two groups in humans: dystroglycan and laminin on the one hand, and GPR56 and collagen III on the other. Finally, molecules secreted by the meninges and acting on the cerebellum begin to be demonstrated; such is the case of SDF1 secreted under the action of FOXC1.

1900 ◽  
Vol 39 (3) ◽  
pp. 685-702 ◽  
Author(s):  
Robert Kennedy

From the point of view of its function, a nerve fibre is a conductor of nervous impulses, and as such is the path of communication between two structures, the one situated in the central nervous system, and the other in the periphery. In the mixed nerve, such as the sciatic, the nerve fibres are distinguished as afferent or as efferent, according as they conduct impulses originating at the periphery, and received by a cell in the central nervous system, or vice versâ. It has long since been shown that nerve fibres are capable of conducting impulses in either direction, but normally, from their anatomical connections, the individual nerve fibres are conductors for impulses only in the one or in the other direction. This is proved by the Wallerian method of investigation, as on severance of the posterior spinal root distal to the ganglion only certain fibres degenerate and the conductivity of the nerve only for afferent impulses is lost, while the severance of the anterior root is followed by the degeneration of the remainder with loss of functions depending on efferent impulses.


1960 ◽  
Vol 106 (442) ◽  
pp. 76-92 ◽  
Author(s):  
Edward Marley

Nearly one hundred years ago, Anstie (1864) wrote: “Among the too frequent instances which are to be found in medical nomenclature, of confusion and uncertainty in the application of descriptive terms, there is none, perhaps, more striking than is occupied by the words Narcotic and Stimulant.” Both classes of substance embrace drugs of antiquity. Thus of the depressants, alcohol dates from the time of the Thracian god, Dionysus, while the earliest use of stimulants such as caffeine and xanthine is lost in the obscurity of the past (Goodman and Gilman, 1955a). Even today, there exists no systematized codification of response to the two classes of drug, although it is implicitly assumed that stimulants and depressants are invariably and mutually antagonistic in their effect on the central nervous system. Advantage was therefore taken of phenomena arising during drug intoxications to categorize abnormal features in the central nervous system common to each of the two classes of intoxicant and to essay a comparison, the one with the other.


2018 ◽  
Vol 23 (1) ◽  
pp. 10-13
Author(s):  
James B. Talmage ◽  
Jay Blaisdell

Abstract Injuries that affect the central nervous system (CNS) can be catastrophic because they involve the brain or spinal cord, and determining the underlying clinical cause of impairment is essential in using the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), in part because the AMA Guides addresses neurological impairment in several chapters. Unlike the musculoskeletal chapters, Chapter 13, The Central and Peripheral Nervous System, does not use grades, grade modifiers, and a net adjustment formula; rather the chapter uses an approach that is similar to that in prior editions of the AMA Guides. The following steps can be used to perform a CNS rating: 1) evaluate all four major categories of cerebral impairment, and choose the one that is most severe; 2) rate the single most severe cerebral impairment of the four major categories; 3) rate all other impairments that are due to neurogenic problems; and 4) combine the rating of the single most severe category of cerebral impairment with the ratings of all other impairments. Because some neurological dysfunctions are rated elsewhere in the AMA Guides, Sixth Edition, the evaluator may consult Table 13-1 to verify the appropriate chapter to use.


Development ◽  
1964 ◽  
Vol 12 (2) ◽  
pp. 317-331
Author(s):  
D. O. E. Gebhardt ◽  
P. D. Nieuwkoop

The influence of lithium on the amphibian egg has been the subject of a number of investigations. From the work of Lehmann (1937), Töndury (1938), and Pasteels (1945) it is known that exposure of amphibian embryos to lithium results in a progressive cranio-caudal reduction of the central nervous system and a simultaneous conversion of the presumptive notochord into somites. Whereas these experiments were made with whole embryos, attempts have been made in recent years to localize the lithium effect by transplanting or explanting specific parts of the embryo. Gallera (1949), for instance, concluded from his experiments with transplants containing lithium treated presumptive chorda mesoderm, that lithium had reduced the ‘morphogenetic potential’ of this inductor. Lombard (1952), on the other hand, claimed that the susceptibility of amphibian eggs towards lithium was the result of the ion's direct influence on the ectoderm rather than on the presumptive archenteron roof.


1957 ◽  
Vol 34 (3) ◽  
pp. 306-333
Author(s):  
G. M. HUGHES

I. The effects of limb amputation and the cutting of commissures on the movements of the cockroach Blatta orientalis have been investigated with the aid of cinematography. Detailed analyses of changes in posture and rhythm of leg movements are given. 2. It is shown that quite marked changes occur following the amputation of a single leg or the cutting of a single commissure between the thoracic ganglia. 3. Changes following the amputation of a single leg are immediate and are such that the support normally provided by the missing leg is taken over by the two remaining legs on that side. Compensatory movements are also found in the contralateral legs. 4. When two legs of opposite sides are amputated it has been confirmed that the diagonal sequence tends to be adopted, but this is not invariably true. Besides alterations in the rhythm which this may involve, there are again adaptive modifications in the movements of the limbs with respect to the body. 5. When both comrnissures between the meso- and metathoracic ganglia are cut, the hind pair of legs fall out of rhythm with the other four legs. The observations on the effects of cutting commissures stress the importance of intersegmental pathways in co-ordination. 6. It is shown that all modifications following the amputation of legs may be related to the altered mechanical conditions. Some of the important factors involved in normal co-ordination are discussed, and it is suggested that the altered movements would be produced by the operation of these factors under the new conditions. It is concluded that the sensory inflow to the central nervous system is of major importance in the co-ordination of normal movement.


1927 ◽  
Vol 23 (10) ◽  
pp. 1046-1050
Author(s):  
E. V. Sukhova

Speaking about syphilis lesions of the central nervous system, it is impossible not to note that these lesions are among the most severe diseases of the latter. But, on the other hand, their severity is redeemed to some extent by the specific means of combating them which we have in our hands. In this case, the fight against neurolues is reduced not so much to its treatment as to its prevention. Hence the interest with which the question of the influence of various conditions on the occurrence of syphilitic lesions of the central nervous system has recently begun to be comprehensively discussed and the exact causes which, from the general number of syphilitics, distinguish the group subsequently condemned to neurolues have been sought to be elucidated.


2020 ◽  
Vol V (4) ◽  
pp. 16-46
Author(s):  
F. K. Telyatnik

Now I turn to a brief summary of the content of some of the works specially devoted to the study of the cerebellar connections. I am not trying to collect all the literature related to this issue, but will confine myself only to the latest works produced with the help of the method most commonly used at the present time for solving questions about conducting paths, namely the method of rebirth. It must be said that a great service in this relationship was also rendered by the method of development, with the help of which a lot of valuable data were obtained, especially Bekhterev. But I will not dwell on them, since all the data obtained in the works of this author are set forth in the "Conducting Ways" and are already given above. As for the newest work performed according to the method of rebirth, all of them were carried out in such a way that one or another part of the cerebellum was damaged in the animal, or one or the other of its legs, and those regenerations were observed, which followed this damage. My works were produced in the same way, and therefore it is very easy to compare them with the works of other authors. This comparison is also favored by the fact that I produced the coloring of the preparations according to the Marchi method, which was also used by most of the researchers cited below.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Domenico De Berardis ◽  
Stefano Marini ◽  
Monica Piersanti ◽  
Marilde Cavuto ◽  
Giampaolo Perna ◽  
...  

Cholesterol is a core component of the central nervous system, essential for the cell membrane stability and the correct functioning of neurotransmission. It has been observed that cholesterol may be somewhat associated with suicidal behaviours. Therefore, the aim of this paper was to elucidate current facts and views about the role of cholesterol levels in mood disorders. The majority of the studies reviewed in the present paper suggest an interesting relationship between cholesterol (especially lower levels) and suicidality. On the other hand, particularly during the last years, relationships between serum cholesterol and suicidality were doubted on the basis of some recent studies that have not found any correlation. However, the debate on relationships between cholesterol and suicide is open and longitudinal studies on a larger sample of patients are needed to further clarify this important issue.


1959 ◽  
Vol 36 (3) ◽  
pp. 501-511
Author(s):  
M. J. WELLS

1. Octopuses blinded by section of the optic nerves were trained by means of 5-10 V. a.c. shocks to reject objects that they would otherwise take. 2. With trials at 3, 5, or 20 min. intervals, in which the test object was always presented to the same arm, animals learned within four or five trials, thereafter rejecting the test object whenever it was presented. 3. When, after a succession of such negative responses, the object was presented to another arm on the other side of the octopus, the result depended upon the rate of training before the change. Thus the object was taken in the trial immediately following the arm change in nineteen out of twenty-six sets of tests with trials at 3 or 5 min. intervals, but in only two out of twelve sets with trials at 20 min. intervals; further experiments in which changes were made between arms on the same side produced similar results. 4. These results are interpreted as showing that changes occurring as a result of experience directly affecting one arm take a period of several hours to spread and become effective in determining the reactions of the rest. This in turn implies the existence of functionally independent neurone fields representing the individual arms, and is discussed in relation to what is already known about the organization of the tactile system of the octopus.


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