662 



PHYSIOLOGY OF THE CEREBRUM 



Soon the ability to form ideas is developed, by which we mean that the 

 child learns to include the single concrete objects of the same kind under a 

 common designation. And as his mental powers develop still further, he conies 

 to incorporate into his circle of ideas notions concerning the relations of objects 

 to one another, notions of their properties, their position in time and space, 

 etc. Finally, the abstract ideas also begin to be more than mere words for the 

 child, and a view of the world, as yet of course very vague and indefinite, 

 becomes his own. 



In all this course of development of the mental powers, speech plays a 

 determining part and this part becomes more significant the more the child 

 comes to rely upon abstract ideas. He requires no great store of words to rep- 

 resent objects themselves and their simplest relations to each other, for direct 

 contemplation will serve him here. But when it comes to more complicated 



FIG. 296. Diagram of the speech tract together with the various centers of the cerebral cortex 

 concerned in speech. L, area of the image of speech movements; A, area of word-sound 

 memory; O, area of memory for the optic images of writing; Occ.I., O.H., O.III., first to 

 third occipital convolutions; F I., F II., first and second frontal convolutions; F III., third 

 frontal convolution (Broca's area); T I., T II., T III., first to third temporal convolutions; 

 Cp., posterior central convolution; Pi., inferior parietal gyrus; 7ns., ieland of Reil; ai, asso- 

 ciation tracts between L and the central portions of the association areas; Li., motor speech 

 tract. 



relations of concrete objects, and especially to abstract ideas, a satisfactory 

 conception can only be gained through the medium of language. 



The names of concrete objects have therefore much less significance for 

 our mental operations than the words by which we designate abstract ideas, 

 and we may conclude from this that the latter require a more complex order of 

 activity on the part of the brain than the former. Accordingly we find in 

 certain disorders of speech resulting from injuries in the brain e. g., in lighter 

 forms of the so-called amnestic aphasia that the patients forget proper names 

 and the names of things, while abstract substantives, verbs, adjectives, conjunc- 

 tions, etc., are retained. 



