PAPERS ON MEDICINE AND PUBLIC HEALTH 265 



The educational principle has a preponderating applica- 

 tion in lesions of motor gray matter when those lesions are 

 end results or residui of pathologic or traumatic processes. 



These residui are the most frequent lesions of gray mat- 

 ter. 



They group themselves into the cerebral palsies and the 

 spinal palsies. TjiDical of the former is birth palsy. Here 

 hemorrhage or inflammatory changes have occurred affect- 

 ing the Rolandic areas with consequent atrophy of gray 

 cells. The functional effects of such lesions are seen in 

 spastic paralyses of skeletal muscles of greater or less 

 extent. 



TjT^ical of spinal palsies is anterior polyomyelitis. 

 Here there is toxic atrophy of gray cells in the anterior 

 horns. Functional effects are seen in flaccid paralyses of 

 skeletal muscles. 



What recovery can be hoped and how can it be effected? 



The usual points of attack are the muscles themselves, 

 and their vascular and nerve supplies. 



It is fondly hoped that atrophy can be limited by stimulat- 

 ing the muscles and nerves and mechanically inducing 

 greater vascular activity. It is sometimes thought that by 

 sending the electric current through the neuromuscular 

 system function may be restored. But such effects have 

 never been produced by these means, as the means are no 

 more adapted to the ends sought than the stimulation of an 

 electric light bulb and its contents is adapted to reactivating 

 a damaged motor. Whatever results have been achieved are 

 to be attributed to nature's unaided efforts as seen in 

 hygienic and trophic-instinctive effects. 



Gray matter responds directly only to educational efforts. 

 Educational results are characterized by more complex and 

 finely adaptive arrangements and contacts between gray 

 cells through their arborizations. It is in the unhurt but 

 hitherto unused surplus of gray cells that our hope lies. 



New paths for the transfer of motor impulses possibly 

 may be found, and new arrangements in cell groups when 

 partial damage has been done may be achieved. 



