CHAP. XXVI.] VOLUNTARY MOVEMENTS. 583 



impressed at the time of the publication of his work, is 

 unquestionably defective, and stands in need of revision. 



(c.) According to Hitzig, and also to Nothnagel, the 

 affection of Motility resulting from the destruction of the 

 cortical regions in question is due to a paralysis of the 

 animal's ' muscular sense.' Nothnagel thinks the fact of 

 the recovery of Movement after a time in dogs proves that 

 the centre of the ' muscular sense ' is not itself destroyed, 

 but that the destruction of the particular regions of the 

 cortex has sufficed to interrupt, for a time, and not far 

 from their termini, the paths for such ingoing impressions. 

 Hitzig, on the other hand, seems more inclined to believe 

 that the centre itself (' End-station ') for impressions of the 

 * muscular sense ' or ' muscle-consciousness ' is destroyed 

 by the experimental lesions. Or, if this be not the case, 

 he, like Nothnagel, is disposed to believe that the afferent 

 path from muscle to ' mind ' is in some way interrupted. 

 Both these investigators, in further support of their 

 notion, say that the condition of the animal, in regard 

 to Motility, is somewhat similar to that of a Man who is 

 suffering from the disease known as ' locomotor ataxy.' 



Ferrier, in opposition to this view, contends that " loss 

 of the muscular sense without any affection of the other 

 forms of common or tactile sensibility is a condition the 

 existence of which is purely hypothetical." He further 

 considers that no investigations bearing upon the subject 

 have furnished the slightest evidence of impairment or 

 loss of Touch or Common Sensibility when his so-called 

 ' motor centres ' have been destroyed : hence he infers that 

 the ' muscular sense ' has also remained unimpaired (see 

 p. 69). The affection of motility met with after destruction 

 of the so-called ' motor centres,' he says, " only resembles 

 ataxia in the case of the cat, dog, &c.; but in man and 



