FUNCTIONS OF THE BRAIN. 55 



those, namely, of vision, touch, etc., without leaning on the 

 auditory region. It is the minuter analysis of the facts in 

 the light of such individual differences as these which con- 

 stitutes Charcot's contribution towards clearing up the 

 subject. 



Every namable thing, act, or relation has numerous 

 properties, qualities, or aspects. In our minds the proper- 

 ties of each thing, together with its name, form an associated 

 group. If different parts of the brain are severally con- 

 cerned with the several properties, and a farther part with 

 the hearing, and still another with the uttering, of the name, 

 there must inevitably be brought about (through the law of 

 association which we shall later study) such a dynamic connec- 

 tion amongst all these brain-parts that the activity of anyone 

 of them will be likely to awaken the activity of all the rest. 

 When we are talking as we think, the ultimate process is that 

 of utterance. If the brain-part for that be injured, speech 

 is impossible or disorderly, even though all the other brain- 

 parts be intact : and this is just the condition of things 

 which, on page 37, we found to be brought about by 

 limited lesion of the left inferior frontal convolution. But 

 back of that last act various orders of succession are 

 possible in the associations of a talking man's ideas. The 

 more usual order seems to be from the tactile, visual, or 

 other properties of the things thought-about to the sound 

 of their names, and then to the latter's utterance. But if in 

 a certain individual the thought of the look of an object or 

 of the look of its printed name be the jjrocess which 

 habitually precedes articulation, then the loss of the 

 hearing centre will pro tanto not affect that individual's 

 speech. He will be mentally deaf, i.e. his tinder standing of 

 speech will suffer, but he will not be aphasic. In this way 

 it is possible to explain the seven cases of pxre word-deaf- 

 ness which figure in Dr. Starr's table. 



If this order of association be ingrained and habitual in 

 that individual, injury to his visvcJ centres will make him 

 not only word-blind, but aphasic as well. His speech will 

 become confused in consequence of an occipital lesion. 

 Naunyn, consequentl}^, plotting out on a diagram of the 

 hemisphere the 71 irreproachably reported cases of 



