CuAP. XXIX.] SPEECH AND THOUGHT. 621 



3. — Diminished Excitahility of the Auditory Word- 

 Centres. 



According to the degree in which the proper vitality 

 of the Auditory Word- Centres is affected, we may find 

 evidence that they ceaso to respond, first to ' vohtional * 

 incitations, secondly to those coming to them hy way of 

 * association,' and lastly to ' sensory ' impressions coming 

 from without. 



A good example of an ordinary case of Amnesia is 

 thus referred to hy Trousseau in his " Lectures," in which 

 the 'volitional' and ' associational ' recall of names was 

 impossible, though their ' sensory ' recall was preserved. 



" The patient does not speak, because he does not remember the 

 words which express ideas. You recollect the experiment which I 

 often repeated at Marcou's bed-side.* I placed his nightcap on his 

 bed, and asked him what it was. But after looking at it atten- 

 tively he could not say what it was called, and exclaimed, 'And 

 yet I know well what it is, but I cannot recollect.' When told 

 that it was a nightcap, he replied, ' Oh ! yes, it is a nightcap.* 

 The same scene was repeated when various other objects were 

 shown to him. Some things, however, he named well, such as his 

 pij^e. He was, as you know, a navvy ; and, therefore, worked 

 chiefly with the shovel and the pickaxe, so that these are objects 

 the names of which a navvy should not forget. But Marcou could 

 never tell us what tools he worked with, and after he had been 

 vainly trying to remember, when I told him it was with the shovel 

 and the pickaxe, ' Oh ! yes, it is,' he would reply, and two minutes 

 afterwards he was as incapable of naming them as before." 



In the slighter forms of Amnesia the efforts at Eecol- 

 lection of a person who is '' at a loss for a word " tend 

 also to call the Visual Word- Centres into an incipient or 



* The earlier condition of this man will hereafter be referred to 

 (p. 627), as at that time he manifested a distinct tendency to 

 echo ' words. 



