The recent studies on man by Spencer, Meyer, Rehfus, and Hawk have led them to conclude that weak alkalies (sodium bicarbonate) in the stomach hasten the emptying of the stomach by increasing the digestion peristalsis or by opening the pylorus. This is opposed to the generally accepted view of the acid control of the pylorus, as developed by Cannon. If their conclusion is substantiated, we may have the explanation of the allaying of the "hunger pains" in ulcer patients by oral administration of alkalies. That is, the alkalies cause relaxation of the tetanic spasm of the pylorus and antrum, induced reflexly from the duodenum. Glassner and Kreuzfuchs state that in cases of gastric ulcer there is a prolonged tetanic closure of the pylorus when the acid chyme first enters the duodenum. This is a reflex from the duodenum. The body of the stomach is atonic and quiescent during this pyloric spasm. The spasm itself is felt as pain. In cases of duodenal ulcers similar pylorus spasms come on later in digestion and are likewise felt as pains. According to these observers the hunger pains in ulcers are thus due to pylorus spasm, while Hertz ascribes them to contractions of the entire antrum. Pick suggests that the pains are due to mechanical stimulation of the food rather than to the acid stimulation of the ulcer. Ehrlich protests against the view that "painful empty stomach" in ulcer patients is an evidence of neurosis. According to Jacobi, the pains of gastric and duodenal ulcers are due to "hypersecretion, hyperperistalsis, or pressure."
Are the sensations of "hunger pains" identical with the normal pangs of hunger except for their greater degree of painfulness? This question cannot be answered from the clinical literature, and probably will remain unanswered until the clinical investigator himself experiences the pain in ulcer and allied diseases. These pains may lead to or be associated with nausea, but the same is true in normal hunger of some persons and in prolonged starvation. The "peristaltic unrest" of Kussmaul occurs both in the filled and in the empty stomach, in cases of pyloric obstruction and in certain forms of neurosis. The sensations aroused by this condition are said to be similar to cramps rather than to the pangs of hunger. The gastralgokenosis of Boas is thought by this author to be due to the strong contractions of the pyloric part of the stomach towa the end of gastric digestion. Although the pain disappears < taking food, Boas does not identify it with true hunger pair The gastralgia in tabes is generally held to be of central origi but so far as we know the tonus and motor conditions of the stoi ach have not been studied during the gastric crisis of this disea;
-The term "polyphagia" is frequent used in the sense of bulimia or excessive hunger. Other autho confine it to excessive ingestion of food without actual augment tion of the hunger sensation. In this latter sense it implies esse tially delay in or absence of the sensation of satiety. Nicol believed that polyphagia results from anesthesia of the storaai nerves concerned in the sensation of satiety. But true akoria • absence of satiety occurs mainly in hysteria and neurasthenia, ar has probably nothing in common with such a condition as tl polyphagia in diabetes.
The diminution or absence of hunger and appeti in gastero-enteritis, in fevers, and in cachexia, etc., are in all prol ability associated with atony of the stomach and absence of ti gastric hunger contractions. The evidence for this view will I presented later. The true anorexia nervosa is probably of moi complex origin, involving both central and peripheral factor There may be atony and absence of the gastric hunger contractioi even in cases where no organic lesion in the stomach can be demoi strated. In some cases of anorexia Ewald found pathologic changes in the mucous membrane of the mouth, suggesting disordei of the sense of taste.
When the anorexia is very marked it may be accompanied b nausea, at least at the sight, smell, or taste of food, or an actu; fear of food and eating (sitophobia). Under other conditions mild nausea may be present synchronously with practically norm; hunger and appetite (Boas). We have seen that this may occi in normal individuals in prolonged starvation. Nervous anorexi is more common in women than in men. Vertes takes the positio that most of the disturbances of hunger and appetite that appea in pregnancy, ovarian diseases, menstrual disorders, etc., are i reality independent of the latter, while in a few cases, they are reflex neuroses. The actual state of the gastric hunger mechanism in these conditions is not known.
This term is used to designate various types of abnormal, perverted, or depraved appetite. These conditions refer exclusively to appetite, rather than to hunger, at least it has not been shown that hunger is at all involved. The least abnormal condition appears to be the malaria, or desire for highly spiced or acid foods that are sometimes seen in chlorotic girls and in pregnant women. Another type-pica-is the appetite for substances that are not food, such as clay, chalk, or earth. These materials are eaten, especially by children, because they like the taste of them. This is probably a bad habit, rather than an indication of seriously perverted mental processes. Most of our domestic animals, even those that appear perfectly healthy, eat earth at times, aside from the quantity of earth consumed with their ordinary food and drink. And even with the best of care in the way of food hygiene, we all consume more or less earth, dirt, stable manure, etc., with our food. To the mind of the average adult earth has become synonymous with dirt or filth, hence we abhor taking it into the mouth, just as the average person loathes snakes. The child, not having formed these associations, puts sand, chalk, or earth into his mouth from general curiosity or in the spirit of play, and may or may not like the new experience. If he likes it, he will repeat it until he learns the usual social canons. Clay eating is on a par with gum chewing and tobacco chewing, and is certainly less injurious and nasty than the latter habit.
Allotriophagia, or desire for disgusting and offensive sub-tances, such as human excreta, body lice, etc., is practically confined to insane individuals, or extreme degenerates. It is likely that the habit is reached via the route of sexual depravity, at least in many cases. In persons with the ordinary idea-associations lost or suppressed, tolerance and even liking for any kind of taste and odor can apparently be cultivated. We all know that animal excreta are regularly ingested by many normal animals, though most of them pass by those of their own species.