698 THE CEREBRUM 



Agraphia. — As a second means of communicating our ideas to our 

 fellow-men, we employ a code of written signals which are in no way 

 less arbitrary than those of speech. They differ with the character 

 of the language and hence, also with the intelligence of the people 

 employing them. Like speech, writing is a skillful act and is controlled 

 by a number of cortical centers. Both faculties are acquired and may 

 be perfected by training. First of all, we observe that the muscles of 

 the hand and fingers are controlled by certain units of the motor area. 

 These in turn are under the guidance of a psychomotor area of the 

 cortex which, as far as is known, occupies a position in or very near to 

 the psychomotor center for speech. Secondly, as writing is the direct 

 outcome of associative processes in different sensory regions of the 

 cortex, the latter may be regarded as tributary areas to the chief psy- 

 chomotor center. 



Theoretically considered, therefore, we might recognize the exist- 

 ence of a distinct writing-circuit, similar in its outline to the speech 

 circuit. In strict analogy to the latter, it might be said to possess 

 a sensory and a motor side, the ingoing impulses being derived chiefly 

 from the visual and auditory centers. While this conception is un- 

 doubtedly correct physiologically, no pathological cases have been 

 recorded as yet which might prove the power of writing to be a separate 

 cortical entity. In fact, the records show that agraphia or loss of the 

 power of writing, is present only in connection with at least a slight 

 degree of aphasia. This is also true of paragraphia, i.e., the writing 

 of wrong words, syllables and letters. Agraphia, however, is due to a 

 lesion of those psychic centers which are directly concerned with the act 

 of writing. Hence, writer's cramp is not an agraphia, but is due in all 

 probability to a neurosis of psychogenic origin. Thus, this condition 

 is comparable to those disturbances in speech which are classified 

 as stuttering and stammering. Very characteristic defects in writing 

 are exhibited in different psychoses. The paralytic writes carelessly, 

 leaving out words and syllables, while the maniac writes very hastily 

 and the katatonic in a peculiar stilted manner. It may be concluded, 

 therefore, that speech and writing are closely related, acquired and 

 educative faculties. Their motor centers, paths and end-organs are 

 quite distinct, but on the sensory side we find that practically the same 

 psychic areas are involved in the two processes. This fact accounts 

 for the close relationship existing between agraphia and aphasia. 



It has also been claimed by Kussmaul that our musical faculties 

 are "separately represented in the cerebral cortex. This implies that 

 the psycho-visual and psycho-auditory regions embrace a circumscribed 

 area in which musical symbols and sounds are associated. This con- 

 clusion is based upon the fact that the power of reading musical notes 

 may be preserved in alexia.^ A condition of amusia, however, has 

 been repeatedly observed in consequence of cerebral lesions. 



1 Oppenheim, Charity Ann., 1888, 345. 



