A few individual cases of taste synæsthesia have been studied in some detail. Such individuals are often shown to have a defective sense of taste and to rely largely, in their recognition of taste, on touch accompaniments, affective characteristics, and such “color” experiences as the various tastes are said to induce.
Perversions of Taste
Under certain unusual organic conditions, and also still more commonly in the case of degenerate and neurotic individuals, various perversions of taste occur. These perversions do not seem to be exclusively gustatory in character, since they involve more general factors, such as appetite, craving, and emotional disturbance. The name parorexia is sometimes given to these perversions of taste and appetite. One of the subforms, known as malacia, takes the form of an urgent desire for hot spices, or for sour and acid foods, such as pickles. What is known as “salt hunger” is a very similar condition, especially often found among the lower animals. Another form of such perversion, known as pica, shows itself in the desire to eat such substances as clay, chalk, and similar gritty or earthy substances. Especially often among children and among certain primitive peoples the chewing of these substances often seems to give a satisfaction quite unfamiliar to the majority of mankind. Little is known about such perversions beyond the fact that they have often been reported.
Under certain conditions of mental degeneracy and nervous disorder perversions sometimes arise which have been classed under the term allotriophagia. This perversion takes the form of eating with apparent relish various kinds of filth which are commonly offensive and disgusting. In these cases it is quite possible that there is no genuine taste disorder. Many, if, indeed, not most, of our revulsions against substances known as filth arise on the basis of associated circumstances, rather than on the simple basis of their taste qualities. The falling away, or deterioration, of these associative and æsthetic controls in the case of the demented and degenerate, and their absence in the case of the feeble-minded and imbecile, may easily lead to reactions which suggest but do not necessarily involve genuine taste disorder.
CHAPTER XIII
Food and Flavor
The Biological Rôle of Taste
In considering the function of the sense of taste it is common to dismiss the topic in a summary manner by pointing out the fact, that in its original primitive conditions, at least, this sense enables the organism to discriminate between wholesome and deleterious food. This function is, of course, not to be neglected, especially if due credit be given to the rôle played by smell in the same service. It is however true that, although the indications of taste and smell may be, for lower forms of animal life, fairly trustworthy guides in the selection of edible substances, such criteria as taste and odor can by no means be relied on by human beings. In a general way it is, of course, true that wholesome substances possess taste qualities which are agreeable and enjoyable, while foul, decaying and poisonous substances are often characterized by tastes and odors that arouse in us disgust and revulsion.
But in the complex lives of human beings, at least, this sort of natural adaptation is far from adequate to constitute a dietetic guide. Not only is it true that many substances accessible to human beings are injurious and unwholesome, in spite of their agreeable taste; it is equally true that many substances that are initially distasteful may be either nourishing or remedial. Human beings find it necessary to supplement, or even to supplant, the “beneficent guardianship” of taste by the introduction of various other sources of information and criteria of selection.
We do not find, however, that the sense of taste shows any evidence of deterioration as the result of such loss of function. Probably never before in the history of our race has there been such diligence and zeal in ministering to the demands and satisfactions of our appetite. In the preparation, marketing, and serving of food the appeal through tastefulness and flavor stands second only to that through purity and cleanliness. The situation is neatly stated by Jane Addams in the following words: “Perhaps the neighborhood estimate (of their New England kitchen) was summed up by the woman who frankly confessed that the food was certainly nutritious, but that she didn’t like to eat what was nutritious; that she liked to eat ‘what she’d ruther.’”