THE ANATOMICAL RECORD 216:474-482 (1986) Variation in Human Fungiform Taste Bud Densities Among Regions and Subjects INGLIS J. MILLER, JR. Department of Anatomy, Bowman Gray Schoot of Medicine, Wake Forest University, Winston-Salem, NC 27103 ABSTRACT Taste sensitivity is known to vary among regions of the tongue and between subjects. The distribution of taste buds on the human tongue is examined in this report to determine if interregional and intersubject variation of taste bud density might account for some of the variation in human taste sensitivity. The subjects were ten males, aged 22-80 years, who died from acute trauma or a n acute cardiovascular episode. Specimens were obtained as anatomical gifts or from autopsy. A sample of tissue about 1cm2 was taken from the tongue tip and midlateral region; frozen sections were prepared for light microscopy; and serial sections were examined by light microscopy to count the taste buds. The average taste bud (tb) density on the tongue tip was 116 tblcm2 with a range from 3.6 to 514 among subjects. The number of gustatory papillae on the tip averaged 24.5 papillaelcm' with a range from 2.4 to 80. Taste bud density in the midregion averaged 25.2 tbl cm2 (range: 045.91, and the mean number of gustatory papillae was 8.25/cm2(range: 0-28). The mean number of taste buds per papilla was 3.8 2.2 (s.d.) on the tip and 2.6 5 1.5 (s.d.1 on the midregion. Subjects with the highest taste bud densities on the tip also had the highest densities in the midregion and the highest number of taste buds per papilla. Taste bud density was 4.6 times higher on the tip than the midregion, which probably accounts for some of the regional difference in taste sensitivity. The difference of more than 2 log units in taste bud density probably accounts for some differences in taste sensitivity among human subjects. The regional density and distribution of taste buds has not been quantified on the human tongue. Taste thresholds are known to vary among different regions of the tongue (Collings, 1974). Diminished taste sensitivity among human subjects has been attributed to genetic factors (Kalmus, 19711, aging (Murphy, 1979; Schiffman et al., 1979; Grzegorczyk et al., 19791, and disease (Snow, 1983). Taste intensity in normal human subjects is proportional to the number of fungiform papillae which are stimulated (Smith, 1971), and the number of taste qualities elicited by stimulation of individual fungiform papillae is greater for papillae with multiple taste buds (Arvidson and Freiberg, 1980).We hypothesize that some of the variation in taste sensitivity found in human population may be attributable to differences in the numerical density or regional distribution of the taste buds. Quantification of human fungiform taste buds has come from excised papillae. Papillae taken from 22 cadaver tongues (Arvidson, 1979) or from 31 living volunteers (Arvidson and Freiberg, 1980) yielded comparable results. Over half of the papillae contained no taste buds. About one-fourth of the papillae contained one to three taste buds, and 10-20% contained four taste buds or more. From three to 21 papillae were sampled per subject in the earlier report of Arvidson (1979), and no taste buds were found in the sample from three subjects. From 5 to 85% of the excised papillae contained taste buds among the 22 cadaver subjects. In a study of hu0 1986 ALAN R. LISS, INC. man taste buds by transmission electron microscopy, three to five papillae were excised from 11 volunteers; but taste buds were reported in the samples from only three subjects (Paran et al., 1970). It is not clear from excised papillae whether differences in the prevalence of taste buds among subjects were due to chance in the sampling of fungiform papillae or whether there is a significant difference in the number or distribution of fungiform taste buds among humans. The distribution of taste buds was studied in two regions (tip vs. midlateral) of the human tongue for a population of ten male subjects. These two regions were selected because of documented differences in their taste thresholds. No information was available on the taste abilities of the subjects, but all died from acute causes (trauma or vascular episode) and were presumed to represent a normal gustatory population. The number of available specimens for this study was limited, so the population included both Blacks and Whites and a range in ages of 58 years. In order to avoid the problem of sampling papillae described above, the entire taste bud population in the selected region was quantified with serial microscopy. The objective was to compare the number of taste buds among regions and among subjects to determine if there were substantive differences which could account for variations in human taste sensitivity. Received June 4,1986; accepted July 22,1986 475 VARIATION IN HUMAN TASTE BUD DENSITIES Fig. 1. Human cadaver tongue. The photograph (left) is montaged to show fungiform papillae in focus on the tongue tip and in the middle regions. A millimeter scale is located on the back of the tongue. The diagram (right) indicates the regions from which samples are taken from the tongue tip and midregion. MATERIALS AND METHODS Observations were made on ten human tongues obtained from anatomical gifts and autopsy specimens by the Departments of Anatomy and Pathology, Bowman Gray School of Medicine of Wake Forest University. The subjects ranged in age from 22 to 80 years at death. All subjects were males including three Blacks and seven Caucasians who died of acute trauma or acute cardiovascular episodes. Tongues were removed from perfused cadavers or obtained fresh from autopsy. All specimens were washed in tap water and fixed in AAF (ethyl alcohol; acetic acidformalin) in the refrigerator at 4°C. Fixed tongues were photographed, and observations were referred to a schematic drawing of the photograph. A tissue block about 1cm2 was cut from the tongue tip and midregion, respectively, for light microscopy. The blocks were washed in running tap water and dehydrated in 30% sucrose. The tissue was frozen in O.C.T. Compound (Miles Scientific), cut a t 20 pm in a cryostat, mounted on slides, and stained with hematoxylin and eosin. Serial sections were examined and the locations of taste buds on papillae were measured from the cut edges of the tissue block. A diagram of the locations of taste buds was referred to photographs of the tongue to identify the specific papillae on which taste buds were found. RESULTS Figure 1 shows a human cadaver tongue with a diagram of the regions sampled for taste bud density. A montaged picture is used to show papillae on the tip and in the posterior regions from different planes of focus. The area containing fungiform papillae extends rostra1 from the circumvallate papillae to the tongue tip excluding a region along the central midline. The size of the tongue varied in proportion to the body, and averaged about 50 cm2 among subjects. Its surface area shrunk with fixation and dehydration, and fissures became more prominent. The sampled areas on the tip and midregion of ten cadaver tongues averaged 1.24 and 1.25 cm2, respectively. Examples of fungiform papillae containing taste buds are shown in Figure 2 (arrows). Papillae with taste buds (Fig. 2D) varied in structure from the typical “fungiform” or mushroom-shaped type with slender necks and enlarged heads (Fig. 2B) to inconspicuous bumps 476 I.J. MILLER, JR. Fig. 2. Photomicrographs of sections from human tongues. A) Arrows indicate taste buds on a classical fungiform papilla. X 50. B) The same section as in A shows variations in the shape and height of gustatory papillae (stars). X 5. C) Gustatory papillae which are not of the typical “fungiform” shape. x 5. D) A human taste bud with a pore at the lingual surface. x 400. (Fig. 2 C) scarcely elevated from the surrounding epithelial surface. Determination of the proportion of papillae containing taste buds would require a n arbitrary definition of which papillae without taste buds to include in the calculation. Variation among subjects in the morphology of papillae, with and without taste buds, requires a separate report. Instead, this report focused on gustatory papillae, viz. those bearing taste buds. A sample from the tip region of specimen 25 is shown in Figure 3. Stars mark the papillae which contained taste buds, and the diagram indicates the number of taste buds in each of the papillae. This sample occupied a n area of 0.84 cm2 with 19 gustatory papillae containing 152 taste buds. Taste buds are most dense along the margin of the tip, and their papillae are grouped into clusters. The subject was a 29-year-old white male who died of acute trauma. Table 1shows the densities of taste buds and gustatory papillae among the population of ten subjects. The subject number (column 1) was arbitrarily assigned for ref- 477 VARIATION IN HUMAN TASTE BUD DENSITIES TABLE 1. Taste bud and gustatory papilla density' Subject Tip region Age/ Tb/ (years) Taste buds/cm2 Papillae/(cm2) pap 16 33 34 7 35 27 2 15 25 26 22 53 22 75 80 56 79 53 29 70 3.6 4.9 18.7 23.2 44.0 74.5 148.5 160.7 170.8 514.0 2.4 3.3 3.7 9.5 26.8 27.3 32.1 38.6 21.4 80.0 Mean SD 51.5 22.8 116.3 154.4 24.5 23.5 Midregion Tb/ Taste buds/cm2 Papillae/(cm2) pap 8.0 6.4 22.9 3.0 0 2.0 17.7 8.4 68.7 19.0 24.5 85.9 9.3 1.5 0 2.0 11.3 3.2 17.3 4.8 4.4 28.2 2.5 2.0 0 1.0 1.6 2.7 4.1 4.0 5.6 3.0 3.8 2.2 25.2 29.1 8.2 8.8 2.6 1.5 1.5 1.5 5.0 2.4 1.6 2.7 4.6 4.0 'tb, taste bud; pap, papilla. Fig. 3.Tip region of the tongue from subject 25. The most anterior portion lies downward. Stars on the top photo show the locations of papillae with taste buds. The diagram below shows the number of taste buds in individual papillae. x 9. erence. Column 2 contains the age of the subjects at death. Column 3 was calculated by dividing the number of taste buds by the surface area of the sample from the tongue tip, and column 6 has the taste bud density of the sample from the midregion calculated in the same way. Subjects are listed in the order of increasing taste bud density on the tongue tip. The densities of gustatory papillae from the tip and midregion are shown in col- umns 4 and 7, respectively. Columns 5 and 8, containing the average number of taste buds per papilla for the tip and midregion, respectively, were calculated by dividing the total number of taste buds by the number of gustatory papillae for each sample. The density of papillae which contained taste buds on the samples of tip region (column 4) averaged 24.5 + 23.5 (s.d.)/cm2 among subjects with a range from 2.4 to 80. The tip contained fewer than 5 papillae/cm2 in three subjects, about 10 papillae/cm2 (9.5) in one subject, between 20 and 40 papillae/cm2 in five subjects, and 80 papillae/cm2 in one subject. Subjects averaged 3.8 2.2 (s.d.1 taste buds/gustatory papilla on the tip (column 5) with a range from 1.5 to eight. Eight of ten subjects had papillae with five or more taste buds; four subjects had papillae with ten or more taste buds; and three subjects had papillae with 15 taste buds or more. Papillae with ten or more taste buds were found only on tongue tips with densities of 148 tbs/cm2 or greater. Individual papillae contained from one to 18 taste buds on the tip. Seventy percent of papillae contained five taste buds or fewer, and the median number of taste buds per papillae was three. Papillae containing a single taste bud (72 or 25%) were the most numerous. Twentythree percent of papillae had between six and ten taste buds, and 11-15 taste buds were found on 5%of papillae. Seven papillae (2%) had 15 taste buds or more, and five of these occurred on one specimen (No. 26). The taste bud density (Table 1) on the tongue tip averaged 116 per cm2 for the ten subjects. There was a range from 3.6 to 514 taste buds per unit area (tbs/cm2) with a standard deviation of 154. Two subjects (16 and 33) had less than 10 tbs/cm2; four specimens (34, 7, 35, and 27) contained between 10 and 100 tbs/cm2; on three tongues (2,15, and 25), 148-170 tbs/cm2 were found; and one tongue (26) had 514 tbs/cm2 on the tip. The mean number of taste buds per papilla (by subjects) noted above points to differences among subjects. Two subjects (16 and 33) had less than 5 tbs/cm2 on the tip, and the papillae contained only one or two taste buds each. Subject 34 had a low taste bud density but a higher-than-average number of taste buds per papilla. Subject 27 had a n average number of gustatory papillae in the sample but a below-average number of taste buds 478 I.J. MILLER, JR Fig. 4. Midregion sample from subject 2. The lateral margin of the tongue is in the lower portion of the photo. Stars indicate papillae with taste buds. Note that stars along the lateral margin are found on structures which are not typical fungiform papillae. x 7. per papilla and per cm2. Note that division of the mean taste bud density (116.3) by the mean number of gustatory papillae (24.5) yields a n average of 4.7 taste buds per papilla. This quotient is substantially weighted by subject 26, whose taste bud density and papilla density were more than 2 standard deviations above the mean (Table 1). The average of 3.8 taste buddpapilla gives equal weighting to each subject. Figure 4 illustrates a tissue sample from the midregion of a 79-year-old white male (subject 2) who died after a stroke. The region comprised 1.5 cm2 of surface and contained 26 gustatory papillae with a total of 106 taste buds. The lateral margin of the tongue is located on the lower part of the figure. A companion diagram shows the number of taste buds on each papilla. Gustatory papillae differ in size and shape, containing from one to nine taste buds. The form of structures with taste buds varies from the classical fungiform shape toward the midline to small elevations and ridges along the lateral margin. Taste buds are most abundant near the margin. Like the example from the tip, gustatory papillae are not distributed evenly across the surface but appear grouped into clusters. The midregion samples of the ten subjects contained from 0 to 28.2 gustatory papillae per cm2 with a mean of 8.2 & 8.8 (s.d.) (column 7, Table 1).One specimen had no gustatory papillae in the midregion. Five specimens had from 1 to 5 papillae/cm2; two samples contained about 10 papillae/cm2; and the remaining two subjects ranged from 17.3 to 28.2 papillae/cm2. The mean number of taste buds per papilla in the midregion was 2.6 k 1.5 with a range from zero to 5.0. One subject had no taste buds in the midregion, and the maximum number of taste buds per papilla was nine. Three subjects had papillae with only one or two taste buds. Papillae from six midregion samples had five or more taste buds per papilla: one with a maximum of six, two with a maximum of eight, and three with a maximum of nine. Papillae with one taste bud comprised 29% of those in the midregion, and 64% of papillae had three taste buds or less. Papillae with five taste buds or more comprised 29.5% of the total in the midregion. Taste bud density in the midregion averaged 25.2 k 29.1 taste buds/cm2 with a range of 0 to 85.9. Four subjects had less than 10 taste buds/cm2; four subjects ranged from 17.7 to 24.5; and two ranged from 68.7 to 85.9. Note that papilla densities for eight of ten subjects fell below the mean. The highest taste bud densities resulted from two factors: higher densities of gustatory papillae and higher numbers of taste buds per papilla than average. The average number of taste buds in the midregion from column 8 (2.6 & 1.5) is lower than the value of 3.05, which is the quotient obtained by dividing the average taste bud density in the midregion (25.2)by the mean number of papillae (8.2). The mean of numbers in column 8 (2.6) gives equal weighting to each subject, 479 VARIATION IN HUMAN TASTE BUD DENSITIES Human Taste Bud Density * 2 TIP f :I 1 2 HID 1 A 2 3 4 5 b 1 8 9 10 II I2 13 I4 15 I b I 7 I8 TASTE BUDS PER PAPILLA 'I 3 1 2 3 4 5 6 7 8 TASTE BUDS PER PAPILLA 5 HID 5 TIP Human Gustatory Pap111a Dmslty I 2 3 4 5 6 7 8 9 10 II I?I3 14 IS Ib I7 I8 TASTE BUD5 PER PAPILLA P A P I 1 2 3 4 5 6 7 . ~ TASTE BUDS PER PAPILLA = a TIP 8 HID L L A E I C n 8 Q 1 2 3 4 S 6 7 8 9 10 ( 1 I 1 I3 14 19 I6 I 7 18 TASTE BUD5 PER PAPILLA 1 1 3 4 S b 7 8 TASTE E M 5 PER PAPILLA Fig. 5. Plots of the taste bud densities (top) and gustatory papilla densities (bottom) among subjects. Specimens are listed in the rank order found in Table 1. Note that the ordinates are plotted on a logarithmic scale. Fig. 6. Frequency distributions of taste buds per papilla by region for three subjects. The speciman numbers are the same as in Figure 5. while the quotient of 3.05 taste buds/papilla is weighted by the taste bud densities of subjects 2 and 26. While the foregoing results have been presented by regions, Figures 5 and 6 emphasize a comparison of regions between subjects. The top panel of Figure 5 shows the density of taste buds, and the bottom panel illustrates the density of gustatory papillae among subjects. Note that the ordinates in Figure 5 are plotted on a logarithmic scale. Filled symbols represent data from the tip region, and the unfilled symbols represent the midregion. Specimens are ordered as in Table 1 according to the density of taste buds on the tongue tip. The slope of the relationship between specimens and density has no special significance except to show that there is a continuous distribution of taste bud densities among subjects from fewer than five to more than 500. The density of taste buds in the midregion generally parallels the density of the tip region among subjects; that is, subjects who had more taste buds on the tip than other subjects also had more taste buds in the midregion. There are two notable exceptions. Specimen 1 had the lowest taste bud density on the tongue tip, but the sev- enth-highest taste bud density on the midregion. The midregion of specimen 3 had no taste buds, but the density of the tongue tip ranked above the two other subjects. The bottom panel of Figure 5 shows the relationship of papilla densities among subjects. The specimens are ordered in the same manner as Table 1. Note that the rank orders of papilla densities follow the pattern of rank orders of taste bud densities. The densities of papillae on the tip divide into two groups of specimens: Specimens 5-10 had more than 20 papillae per cm2. Specimens numbered 1-4 had fewer than ten gustatory papillae per cm2. The densities of papillae on the midregion divided into two partially different groups than those of the tip: Specimens 2-4, 6, 8, and 9 had fewer than five gustatory papillae per cm2, while specimens numbered 1,5, 7, and 10 had nine or more papillae per unit area. The distribution of taste buds per papilla is illustrated in Figure 6 for both tip and midregion in three subjects. The specimen numbers at the top of each graph are the same as in Figure 5. Specimen 2 had four gustatory 480 I.J. MILLER, JR papillae in the sample from the tip. Two papillae each had one or two taste buds, respectively. The midregion sample had two papillae with two taste buds each. The low taste bud density of this subject was due both to a below-average number of gustatory papillae in each region and a below-average number of taste buds per gustatory papilla. Specimen 5 ranks fifth in taste bud density on the tip and fifth in taste bud density in the midregion. The density of gustatory papillae was about average on the tip and above average in the midregion. The number of taste buds per papilla was below average for both regions due to a predominance of papillae with one or two taste buds. Specimen 8 was above average by all measures of taste bud distribution on the tip. The average number of taste buds per papilla (3.98) reflects the mode of the distribution at two to four taste buds per papilla. While papillae with ten taste buds or more accounted for 11% of papillae on the tip, they represented 26.9% of the taste buds. In the midregion, six papillae contained a total of 24 taste buds. The densities of papillae and taste buds were below average while the average number of taste buds per papilla was above average. DISCUSSION The most striking observation from this study is a difference in taste bud density of 2 log units between the highest and lowest subjects. This observation probably accounts for some of the disparity in taste sensitivity among individuals in a human population, There is a n average 4.6-fold difference in taste bud density on the tongue tip and on a midregion sample. This difference contributes to the disparities in regional taste sensitivity which have been reported for the human tongue. Current results permit a n estimate of the total number of fungiform taste buds on the human tongue. It is estimated that the four subjects with the lowest taste bud densities may have had a n average total of 200 fungiform taste buds per side of the tongue, while the four subjects with the highest densities may have had as many as 2,000 fungiform taste buds per side. Behavioral evidence supports the conclusion that taste sensitivity is proportional to taste bud density. The intensity of taste sensation elicited from a region of the tongue tip at a given concentration of stimulus is proportional to the number of fungiform papillae which are located in the stimulated region (Smith, 1971). Single fungiform papillae are relatively insensitive to chemical stimulation (Harper et al., 1966; McChtcheon and Saunders, 1972; Bealer and Smith, 1975; Cardello, 1978, 1979); hence, ensembles of papillae are probably necessary to convey meaningful taste perception. The more taste buds in a single fungiform papilla, the wider variety of taste sensations which can be elicited by chemical stimulation of it (Arvidson and Freiberg, 1980). Threshold concentrations for the same stimulus vary among different regions of the tongue (Shore, 1892; Hanig, 1901; Collings, 1974), although the slopes of suprathreshold perceptural intensities are comparable for different regions of the tongue and soft palate (Collings, 1974). The range of taste bud densities among subjects cannot be accounted for by systematic differences due t o age, race, or cause of death. By dividing our sample population in half, the average age of the five subjects with lowest taste bud density is 50.2 years (s.d. = 27.8), while the mean age of the five subjects with the highest taste bud densities is 57.4 years (s.d. = 19.1). Three Blacks out of ten in the group rank fifth, sixth, and tenth in increasing order of tip taste bud density, but this sample is insufficient to determine a trend. Three of the five subjects with the lowest taste bud densities died of acute trauma and two died of acute vascular disorders; three of five of the highest taste bud densities also died of acute trauma, and two died of acute vascular conditions. While the state of health just prior to death is difficult to determine, the prevalence of acute vascular conditions vs. trauma as the cause of death is equally distributed among the halves of the population with the highest and lowest taste bud densities, respectively. There are contrary conclusions about the effects of aging on the number of taste buds and taste functions (Mistretta, 1984; Schiffman et al., 1979). Taste thresholds are reportedly increased in older human subjects (Murphy, 1979; Grezegorczyk et al., 1979) and recognition of foods is lower in elderly subjects than in college students (Schiffman, 1977). Elderly subjects may experience mild dysgeusia without serious loss of taste sensation intensity (Bartoshuk et al., 1986). Average numbers of taste buds per circumvallate papilla diminish with aging in adult humans ( h e y et al., 1935; Mochizuki, 1937). The change in foliate taste buds with aging is equivocal (Mochizuki, 1939),and the average number of taste buds per fungiform papilla seems not to be correlated with the age at death (Arvidson, 1979). Minimal changes attributable to aging were observed in taste bud number in both rats (Mistretta and Baum, 1984) and rhesus monkeys (Bradley et al., 1985). Mistretta (1984) concluded that neither anatomical nor physiological changes reported in taste or olfactory receptors appear to account for alterations in food appreciation reported by elderly human individuals. A few clinical conditions can be cited in which there is both a reduction in the taste bud population and a diminution in taste acuity. Familial dysautonomia is a severe congenital disease in which there is a reduction in taste sensitivity (Smith and Dancis, 1964) as well as an absence (Smith et al., 1965) or reduction (Moses et al., 1967) in the number of fungiform papillae and their taste buds. Curiously, methacholine treatment seems to enhance taste sensitivity in these patients without apparent change in the absence of taste buds (Henkin and Kopin, 1964), which prompted speculation by the authors that taste perception can occur in the absence of taste buds. Patients receiving therapeutic radiation to the head suffer a reduction in taste acuity, while mice subjected to similar radiation treatment show a diminution in the number of taste buds in the circumvallate papilla (Conger and Wells, 1969; Conger, 1973). Sjogren's syndrome includes impairment of salivary secretion, lacrimal gland secretion, and secretion of nasal mucous glands a s well as impairment of both taste and smell (Henkin et al., 1972). Taste buds are decreased in number, and those which persist are abnormal in appearance. From our samples of the tip and midregion densities, a n estimate can be made of the average total number of human fungiform taste buds. The average density of 25 taste buds per cm2 on the midregion may be applicable to approximately 10 cm2 on each side for a total of 250 taste buds per side. The average tip region density of VARIATION IN HUMAN TASTE BUD DENSITIES 116 taste buds per cm2 may apply to about 4 cm2 for a total of 464 taste buds on each side of the tip. The central midline region contains few fungiform papillae in 4 em2 per side, and the number of taste buds in this region is difficult to estimate. Another region which is difficult to estimate is the area of large fungiform papillae which lies between the circumvallate papillae and the central midline. While no systematic study was made of this region, taste buds were observed on some of these papillae. In total, we estimate a n average of 800 fungiform taste buds on each side, which is about twice as many as the estimate of Braus (1940). Hanig (1901) reported that the tongue is most sensitive to sweet and salt on the tip, sour on the sides, and bitter on the back. Collings (1974) studied regional taste sensitivity by threshold determination and by magnitude estimation for a range of concentrations above threshold. Stimuli were applied by circular filter papers 4 mm in diameter to the tip of the tongue and to a region 2.5 cm posterior on the side. The thresholds were lower (more sensitive) on the tip for quinine and sucrose than on the side. The side had a lower threshold for citric acid than the tip, and the thresholds for NaCl were about the same on both regions. The slope of taste intensities was steeper (more sensitive) for quinine on the tip than the side, but slopes for both regions were not different for NaCI, sucrose, and citric acid. The tip contains an average taste bud density 4.6 times greater than the midregion. Taste bud density is determined by two factors: the number of gustatory papillae in a region and the number of taste buds per papilla. The tip has about three times as many gustatory papilla per area as the midregion and about 1.5 times as many taste buds per papilla. The same two factors determine differences among individuals. The correlation between taste bud density and papilla density is 0.89 for the tip and 0.90 for the midregion. Generally, individuals with more gustatory papillae also have more taste buds per papilla. A higher taste bud density on the tip than in the midregion does not account for the differential sensitivity between bitter and sour stimuli. But since bitter sensitivity is most acute in the high taste bud density of the tip, there may be a relationship between relative thresholds to bitter stimuli and relative taste bud densities among subjects. The genetic predisposition for diminished taste sensitivity to phenyl-thio-carbamide (PTC) (Kalmus, 1971) applies also to diminished sensitivity for the bitter taste of saccharin and sweetness of sucrose (Bartoshuk, 1979). These are examples of variable taste sensitivities in a n otherwise healthy population. Arvidson and Freiberg (1980) and Paran et al. (1970) found variable proportions of fungiform papillae with taste buds among young, healthy volunteers. If these samples are indicative of taste bud densities, then they may reveal differences between healthy individuals as large as those in our cadaver specimens. Relative taste bud distributions are difficult to estimate from a small sample of papillae. In conclusion, we find wide variations in fungiform taste bud density in the tongues of human cadavers. 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