THE NATURE OF HUNGER 299 



but to related skin areas. 20 Under such circumstances we do not dis- 

 miss the testimony as worthless merely because it may not point pre- 

 cisely to the source of the trouble. On the contrary, we use such 

 testimony constantly as a basis for judging internal disorders. 



With regard to the contention that reference to the periphery is 

 not proof of the peripheral origin of a sensation, we may answer that 

 the force of that contention depends on the amount of accessory evi- 

 dence which is available. Thus if we see an object come into contact 

 with a finger, we are justified in assuming that the simultaneous sensa- 

 tion of touch which we refer to that finger has resulted from the con- 

 tact, and is not a purely central experience accidentally attributed to 

 an outlying member. Similarly in the case of hunger — all that we 

 need as support for the peripheral reference of the sensation is proof 

 that conditions occur there, simultaneously with hunger pangs, which 

 might reasonably be regarded as giving rise to those pangs. 



Objections to Some Theories that Hunger is of Local Origin 

 With the requirement in mind that peripheral conditions be ade- 

 quate, let us examine the state of the fasting stomach to see whether 

 indeed conditions may be present in times of hunger which would sus- 

 tain the theory that hunger has a local outlying source. 



Hunger not Due to Emptiness of the Stomach. — Among the sug- 

 gestions which have been offered to account for a peripheral origin of 

 the sensation is that of attributing it to emptiness of the stomach. By 

 use of the stomach tube Nicolai found that when his subjects had their 

 first intimation of hunger the stomach was quite empty. But, in other 

 instances, after lavage of the stomach, the sensation did not appear for 

 intervals varying between one and a half and three and a half hours. 21 

 During these intervals the stomach must have been empty, and yet 

 no sensation was experienced. The same testimony was given long 

 before by Beaumont, who, from his observations on Alexis St. Martin, 

 declared that hunger arises some time after the stomach is normally 

 evacuated. 22 Mere emptiness of the organ, therefore, does not explain 

 the phenomenon. 



Hunger not Due to Hydrochloric Acid in the Empty Stomach. — A 

 second theory, apparently suggested by observations on cases of hyper- 

 acidity, is that the ache or pang is due to hydrochloric acid secreted 

 into the stomach while empty. Again the facts are hostile. Nicolai 

 reported that the gastric wash-water from his hungry subjects was 

 neutral or only slightly acid. 23 This testimony confirms Beaumont's 



20 Head, Brain, 1893, XVI., p. 1; 1901, XXIV., p. 345. 



21 Nicolai, ' ' Ueber die Entstehung des Hungergef iihls, ' ' Inaugural-Disserta- 

 tion, Berlin, 1892, p. 17. 



22 Beaumont, ' ' The Physiology of Digestion, ' ' second edition, Burlington, 

 1847, p. 51. 



23 Nicolai, loc. tit., p. 15. 



