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1. Taste, as we ordinarily think of it, is dependent upon all our special senses. 2. Without the sense of smell we have only our basic tastes, namely, sweet, salty, sour, and bitter. 3. In addition, taste perception is influenced by the age, health, attitude, or hunger of the individual. 4. The sense of touch and temperature are also closely allied with the sense of taste. 5. There is a much wider distribution of taste buds in the fetus, infant, and children than in the adult. Our sense of taste diminishes, therefore, as we grow older. 6. There is a gradual shift of taste from the tip of the tongue to the region of the circumvallate papillae. Our sense of taste of sweet and salt diminishes, and the sour is more pronounced. 7. Complete loss of taste, or ageusia, is known to accompany hysterical and other abnormal nervous states. It may be temporary, or, in cases of certain lesions, the sense of taste may be permanently destroyed. 8. The sense of taste may be interfered with or even interrupted by the interjection of an outside stimulus such as a denture or dentures. 9. Pressure or pain acting as a counterirritant may interrupt the sense of taste. 10. Mastication of food on the anterior teeth or undermastication of food may preclude the actual penetration of the material or food in solution into the taste pore.

Summary.-Short-term (5 min.) inrake functions for sucrose were determined for 11 brain-damaged, developmentally retarded children using the singlestimulus-presentation method. Sucrose intake was a decreasing function of concentration. Water intake was equal to or greater than the greatest intake of any concentration of sucrose. These intake functions lacked the ascending limb of intake functions for water and weak concentrations of sucrose which are found in other animal species and in human adults. Evidence supports the notion that severely developmentally retarded children are not ageusic bur can discriminate between various concentrations of sucrose and water. Stimulation of sensory receptors may not only provide information as to the nature of the impinging stimulus but also may have important motivating functions in the control of behavior. Carl Pfaffmann ( 1961) has written often about the sensory and motivating properties of taste. T. C. Schneirla (1959) as well as E. B. Holt (1931) have characterized all behavior as either approach toward a stimulus or withdrawal from a stimulus. Certain taste stimuli such as quinine which has a bitter taste are avoided even in weak concentration by animals, and as the concentration is increased, so is the aversion. Taste stimuli such as salt (sodium chloride) are avoided in weak concentration by animals, but as the concentration is increased, intake increases up to a peak preference point and then decreases as concentration is further increased. Solutions of sugar stimuli (sucrose) are consumed at low concentrations by animals and as the concentration is increased, intake increases until a point is reached at exceedingly high concentrations when the sucrose stimulus becomes aversive. Intake f~~nctions for particular taste stimuli have been obtained in animal species as disparate as flies and monkeys, but few studies have involved non-retarded human adults and children, and none have involved developmentally retarded children. Some authorities such as Mayer-Gross, Slater, and Ruth (1960) are of the opinion that severely developmentally retarded children are impervious to gustatory sensations, basing their notions on the relatively high incidence of pica in this group. Kodman ( 1963) in a review of the sensory processes of the developmentally retarded reported that he was unable to find any large scale study of gustation, but nevertheless, felt that his clinical experience supported the notion of ageusia in the severely developmentally retarded. The purpose of the present study was to find out whether severely developmentally retarded children are indeed ageusic by measuring their short-term intake functions, that is, their drinking behavior, to various concentrations of sucrose and water.

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“ELECTRIC taste” is the sensation elicited on stimulating certain parts of the tongue with a.c. or d.c. current1. A sour or metallic taste, experienced with anodal stimulation of the anterior tongue, is mediated in part by the chordy tympani nerve2. When the chorda is cut, as frequentla necessary in middle ear surgery, the resulting ageusia of the ipsilateral anterior tongue is associated with loss of “electric taste” in the range of current densities usually employed3,4. With a somewhat smaller electrode which delivered higher current density with better localization than in previous studies3,4, testing individual patients on several occasions, we found that the threshold for “electric taste” did not immediately reach the values seen long after surgery. Instead, it rose slowly over a period of weeks. The term “electric taste” is used advisedly: the response to anodal stimulation on the operated side was described by some patients as “stinging” or “pricking”, by others as distinctly “acid” or similar to the normal side.

An evaluation of the effects of partial conduction ageusia on licking an air-stream was undertaken. Rats with bilateral lingual nerve divisions showed significant reductions in pre to post-operative air-drinking rates, while neither rats with severed glossopharyngeal nerves, nor sham operated controls exhibited similar outcomes. Interruption of some sensory input associated with the physical characteristics of an air-stream appeared to exert partial control over responding for air.

(1955). Anosmia and Ageusia, Presumably Resulting from Anoxia. Acta Oto-Laryngologica: Vol. 45, No. 4, pp. 370-372.

Ageusia, the total absence of taste, was demonstrated in 2 patients despite the presence of lingual and palatal papillae which contained taste buds. The ageusia was unchanged after parenteral administration of methacholine. These findings, along with others, suggest to us the classification of these patients as having type II familial dysautonomia to distinguish them from patients with type I familial dysautonomia (Riley-Day syndrome).

IT is well known that the strongly bitter taste of phenyl-thiourea is not noticed by some persons. It is said that 30 per cent of persons of white race do not recognize the taste. The result of tests on Japanese is given below

Gymnema sylvestre (GS), a plant used in the Ayurevedic medicine of India for the treatment of diabetes mellitus1,2, has been known from antiquity also to have an antisaccharin taste effect3–5. Chewing the leaves, rinsing the mouth with aqueous extracts, or topical application to the tongue, selectively and temporarily reduces sensitivity to sweet substances. The mechanism of this selective ageusia or hypoageusia which follows treatment with GS is unknown.

Der genetisch kontrollierte, hohe Geschmacksschwellenwert — Geschmacksblindheit — gegenuber Phenylthioharnstoff (PTC) und anderen bitteren, strukturell ahnlichen Anti-Schilddrusensubstanzen, scheint durch die Qualitat und Quantitat des loslichen Speichel-Enzym-Systems Tyrosiniodinase bedingt zu sein.