THE CEREBELLUM, AND ITS FUNCTIONS. 679 



serial powers. There would seem much more probability in the idea, that 

 it is the special seat of the "muscular sense," which has so important a share 

 in the guidance of the co-ordinated movements ( 536); and this notion de- 

 rives confirmation from the marked structural connection which exists be- 

 tween the Cerebellum and the Optic Ganglia (corpora quadrigemina), the 

 purpose of which may be not unfairly surmised to be, to communicate the 

 guidance of the visual sense to the organ by which the co-ordination of mo- 

 tions is effected, in the same manner as the impressions appertaining to the 

 "muscular sense" are transmitted upwards by the Restiform columns. 1 The 

 chief objection to such a view, would seem to lie in the strong similarity 

 between the "muscular" sense and "common" or "tactile" sensation, which 

 makes it difficult to conceive that they should have different seats in the 

 Sensorium commune. But this difficulty is diminished if not removed by the 

 reflection, that the Restiform columns appear to have the same endowments 

 as the remainder of the Sensory tract derived from the posterior columns of 

 the Spinal Cord; and that no explanation can be given of their extreme 

 sensitiveness to impressions (as shown by experiment), unless it be admitted 

 that the organ in which they terminate is itself a centre of a form of sensa- 

 tion closely allied to that of the common or tactile kind. Possibly, how- 

 ever, the true termination of these fibres is in the "corpus dentatum" of the 

 Crura Cerebelli ; and the Cerebellum may react upon impressions thence 

 transmitted to it, without being itself the instrument of communicating such 

 impressions to the consciousness. 2 Dr. Laycock 3 states that the considera- 



1 This view, sugge>ted many years since by the Author, has been recently sup- 

 ported in the able papers by M. Ph. Ltissanu in the Journal de la Physiologic, torn. 

 v, 1862, p. 481, and torn, vi, p. 169; and also by Mr. Robert Dunn, in his Essay on 

 Physiological Psychology (London, 18-58), who also places the centre of the muscular 

 sense in the, corpus rhomboidale of the Cerebellum. 



2 M. Brown-Se'quard (Journ. de la Physiol., vol. i, 1858, p. 535) and Wagner (Op. 

 cit.) have arrived at almost purely negative results in regard to the function of the 

 Cerebellum. The former experimenter holds that this organ is not a nervous centre 

 for sensitive impressions nor for consciousness, nor is it even a part through which 

 the conductors of motion or of sensation pass; for he believes that no idea, emotion, 

 or voluntary act is suppressed as a consequence of lesion of its structure. Hence he 

 maintain*, that it is not a centre for the faculty of balancing or co-ordination of the 

 symmetrical movements of the body, and that when paralysis is observed after lesion 

 of its structure, it is occasioned (when the paralysis is on the opposite side of the body) 

 by concurrent lesions of other parts, as the Pons Varolii, the Medulla Oblongata, or 

 the Cerebral peduncles; whilst, when the paralysis is on the same side, it is u*tilly 

 due to irritation of certain parts of the Cerebellum reacting on other parts of the En- 

 cephalon, though even from this cause the paralysis may sometimes occur on the 

 opposite side. Though he does not admit it to be a centre for auditory or visual im- 

 pressions, he acknowledges that it has a special influence on vision, having collected 

 60 cases of amaurosis accompanying disease of its structure. (See also on this point 

 the work? of Lussana, Luys, and Renzi.) He has, in a more recent paper (Journ. de 

 la Phys., 1862. torn, v, p. 486), attributed the various effects of Cerebellar lesion, as 

 amaurosis, vomiting, cephalalgia, dilatation of the pupil, general or local convulsive 

 movements, epilepsy, hemiplegia, general debility and disordered movements, con- 

 traction of particular muscles, strabismus, hyperaesthesia, noises in the ears, and ex- 

 aggeration of the sexual desire, to irritation of the Cerebellum, ana not to loss of 



function. He compares these effects with those produced by worms in the intestines. 

 Wagner believes that this organ may become the point de depart of a direct (not reflex) 

 irritation for certain organic muscles, as for those of the abdominal viscera, genera- 

 tive organs, and also, probably, for the heart. Schiff, at the conclusion of his section 

 on the Cerebellum, states simply that " the functions of this organ are still unknown ;" 

 whilst Lussana, in the essay already quoted, finishes by observing that the mnsvnlnr 

 sense and the erotic sense are the two essential functions of the Cerebellum. Prideaux, 

 Med. Times and Gaz., 1864, ii, p. H40, adduces evidence to show that the lateral lobes 

 are the centres of cutaneous sensibility, whilst the central lobe is the centre of mus- 

 cular sensibility. 



3 Med. Times and Gaz., July 12th, 1873. 



