420 MENTAL FUNCTION 



were, summarized for us this conspicuous mass of afferent and efferent 

 nerve-impulses representing much of the stream of consciousness. As 

 we saw in discussing these aspects of mind, every well-defined feeling 

 and every emotion has as an essential part of itself a complex of move- 

 ments within the range of the efferent nerve-impulses. These are largely 

 muscular contractions and strains and changes of tone, but they are in 

 part also innervations of epithelium. Preceding all these we have to 

 suppose a somewhat corresponding multitude of afferent nerve-impulses 

 coming from sense-organs or perhaps only from portions of the brain or 

 the spinal cord. Altogether these represent every portion of the feeling 

 aspect of consciousness through bodily movements and strains, either 

 molar or molecular. These movements and impulses it is the business 

 of psychology to define and describe much more in detail than has yet 

 been done save in the case of three or four emotions. 



In the phase of consciousness which we call volition the bodily 

 accompaniments may be no less universal than in feeling. Here too 

 are concerned the multitude of afferent impulses from the sense-organs 

 which determine especially the reflex aspects of will, while the other side 

 of the nervous arc is concerned with the vegetative musculature, although 

 it may involve any muscle in the body. The actions which are classed 

 physiologically as voluntary or deliberate probably lack these afferent 

 impulses in some degree, and from the fusing process perhaps in the 

 cortex of the brain impulses pass downward which actuate the cross- 

 striated muscles as well as those of the smooth variety. The accom- 

 paniments of the willing process are physiologically of two phases, 

 actuating and inhibitory, but these alike doubtless involve nerve-currents 

 passing to or from nerve-centers. In the determination of choice we can 

 point out the least of bodily concomitance. Morat supposes that there 

 is a continual circulation of nerve-currents in the cortex, and that these 

 in some way accumulate force which the individual uses in typically 

 voluntary movements. 



In cognition the bodily accompaniments are probably as before the 

 sensation-mass represented by almost universal nerve-impulses. Be- 

 sides these there may be an ill-understood process of fusion in the intri- 

 cate maze of the cerebral paths. Besides this general relationship , 

 however, the entire mechanism of speech represents the intellectual 

 functions. When a man thinks clearly, he thinks only in terms of words f 

 usually either spoken or written. When a subject in the laboratory is 

 asked to pick out from one hundred the ten chance ink-blots most like 

 a certain one shown to him, he cannot do so ordinarily without having 

 a clear notion of the similarities in verbal terms in his mind. When 

 one thinks, it is likely that the brain sends out the same impulses that it 

 would send out to the muscles if these words were spoken. The intellect, 

 moreover, does not develop normally if speech of every kind is by any 

 means prevented. In general, then, ideation is impossible without the 

 kinesthetic impulses and motor-innervations which form this physio- 

 logical basis. Many of these innervations are subconscious, but they 

 may not less effect the mind on that account. 



