1895.] Impressions, #c., to Voluntary Movements. 



95 



animals does exist, tending to show that a severance of the visuo- 

 kinfflsthetic fibres (fig. 3, *) is followed by the same kind of paralysis 



Fia. 3. Diagram illustrating relntive Positions of two Cerebral Sensory and one 

 Spinal Motor Centre concerned with Writing Movements. 



K.C. 



VC, visual centre ; KG, kinaestketic centre ; SpMC, spinal motor centre; x', visuo- 

 kinsesthetic commissural fibres ; y, internuncial fibres. 



of limbs as that which results from destruction of the kinsesthetic 

 centres themselves. Thus, Maiique* has found, and his results have 

 been confirmed by Exner and Paneth,f that isolation of the kin- 

 eesthetic centres, by section of the fibres that connect them with the 

 other sensory centres of the cortex, produces a paralysis of precisely 

 the same character as that which occurs when these so-called motor 

 centres are extirpated. Marique, moreover, found that the same kind 

 of muscular contractions were produced on electrical irritation of the 

 respective kinoesthetic centres after, as before, isolation, showing that 

 these centres still retained their excitability and their connection 

 with the pyramidal tracts. 



B. Functional Defects. 



Functional defects leading to paralysis of limbs may be either (a) 

 cerebral or (6) spinal in seat. 



* ' Centres Psycho-moteurs du Cerveau,' 1885. 

 t ' Archiv f. d. Qes. Phys.,' bd. 44, 1889. 



VOL. LVIII. 



