THE ASSOCIATION CENTERS 249 



from the dawn of speculation about the nervous sys- 

 tem until now, numberless attempts have been made 

 on grounds largely speculative to localize somewhere 

 various complex "faculties" or "senses" or associa- 

 tional types as psychological entities. Only recently 

 an eminent medical practitioner announced the exact 

 cortical localization of the "moral sense" on the basis 

 of surface scars on the heads of a few delinquents. 

 The futility of mosaic localization on the surface of 

 the cortex of small areas supposed to perform complex 

 associational functions should by this time be ap- 

 parent. 



There is unquestionably mosaic localization of 

 certain physiological functions in the human cerebral 

 cortex. The projection centers are definite areas 

 within which specific systems of projection fibers 

 make their cortical connections in switchboard fash- 

 ion. But neither these centers nor any sector of the 

 intervening associational tissue can be thought of as 

 performing any one of the distinctively higher cortical 

 functions in isolation (Pike, 1913). The clinicians' 

 maps of the aphasias, etc., represent (in some of the 

 cases) true pictures of vulnerable points of certain 

 associational complexes. But most of the charts of 

 functional localization of psychological or other com- 

 plex functions are misleading fictions. 



The projection centers, I repeat, are definitely 

 localized in mosaic patterns. Surrounding each of the 

 sensory projection areas is a zone of associational cor- 



