Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Taste Threshold”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 397 records · Page 22Linked to original sources
PubMed2004

Posttonsillectomy taste distortion: a significant complication.

OBJECTIVE/HYPOTHESIS: Tonsillectomy is among the most commonly performed procedures. As with any surgery, head and neck surgeons must be aware of possible complications and their potential affects. At our smell and taste center, we have been referred several patients in a 6-month period with the complaint of taste distortion after tonsillectomy. We report in this article a patient that complains of taste distortion after a right tonsillectomy for unilateral tonsillar hypertrophy. STUDY DESIGN: A prospective study documenting taste distortion after tonsillectomy using clinical, subjective, and objective evaluation. METHODS: The clinical course of a patient with taste distortion after a tonsillectomy is described. The gustatory function was investigated by conducting electrogustometry and spatial taste testing. Threshold measurements were determined at three left- and three right-side tongue regions: 1) the tongue tip region (innervated by the chorda tympani branch of the facial nerve), 2) the lateral margin of the tongue (anterior to the foliate papillae), and 3) the posterior tongue region (innervated by the lingual branch of the glossopharyngeal nerve). RESULTS: After a complete clinical evaluation and taste testing, it was found that the patient suffered an injury to the right lingual branch of the glossopharyngeal nerve. The close anatomic relationship between the palatine tonsil and lingual branch of the glossopharyngeal nerve makes the nerve vulnerable during tonsillectomy. This injury has caused the patient to suffer ageusia to the right posterior one third of the tongue, compensated by a contralateral phantogeusia (phantom taste) with clinical dysgeusia. The phantogeusia was abolished by application of anesthetic to the area where the phantom was perceived. We propose that the phantogeusia is the result of release-of-inhibition in the contralateral glossopharyngeal nerve. CONCLUSION: Taste distortion (including, phantogeusia and dysgeusia) after tonsillectomy is rarely reported as a complication but has a significant impact on quality of life. This article examines the taste distortion presence as a complication after tonsillectomy to make head and neck surgeons aware of this serious complication and the pathophysiology of taste distortion.

Dysgeusia↗
PubMedDate not supplied

Rhythmic nature of naloxone-induced aversions and nociception in rats.

Taste conditioning procedures revealed a rhythmic fluctuation in the aversiveness of naloxone in opiate-naive rats. This rhythm exhibited two peaks during each 24-hour period. One peak was evident in the light phase and the second, which was more prominent occurred in the dark phase. Analgesia produced by morphine showed an essentially similar rhythm with heat and pressure as noxious stimuli. Although control nociceptive thresholds for heat also showed this rhythm, those for pressure showed only one broad peak through most of the dark phase. With noxious heat the hyperalgesic effect of naloxone also showed two peaks of activity but, as in control responding, this was not true for pressure. Opioid systems mediating nociception of different stimuli may show differential diurnal fluctuations.

Analgesia↗
PubMed2003

Oral amiloride treatment decreases taste sensitivity to sodium salts in C57BL/6J and DBA/2J mice.

Sodium taste transduction is thought to occur via an amiloride-sensitive, sodium-selective pathway and an amiloride-insensitive, cation nonselective, anion-dependent pathway(s). It has been shown by others that amiloride, an epithelial sodium channel (ENaC) blocker, significantly reduces the chorda tympani nerve response to lingually applied NaCl in C57BL/6 (B6) mice but not in DBA/2 (D2) mice, suggesting that the latter strain might not possess functional ENaCs in taste receptor cells. We psychophysically measured and compared taste detection thresholds of NaCl and sodium gluconate (NaGlu) prepared with and without 100 microM amiloride in these two strains (eight/strain). Mice were trained and tested in a two-response operant signal detection procedure conducted in a gustometer. Surprisingly, no strain effect was found for the detection thresholds of both salts (approximately 0.05-0.06 M). Moreover, these thresholds were increased by almost an order of magnitude by amiloride adulteration of the solutions. This marked effect of amiloride on sodium detection thresholds suggests that ENaCs are necessary for normal sensitivity to sodium salts in both strains. In addition, because NaGlu is thought to stimulate primarily the amiloride-sensitive pathway, especially at low concentrations, the similarity of NaCl and NaGlu thresholds (r > 0.81 both strains) suggests that ENaCs are also sufficient to support the detection of sodium in weak solutions by B6 and D2 mice.

Administration, Oral↗
PubMedDate not supplied

[A comparative study of the taste sensitivity to phenylthiocarbamide in rats differing by the threshold of nervous system excitability].

Taste sensitivity to a bitter substance, phenylthiocarbamide (PTC) was studied in rat strains selected for the threshold of excitability of the nervous system. In the period of 17 days the drinking behaviour of the rats was estimated after giving them a series of PTC solutions with increasing concentrations and water as a control. The interstrain differences were found in the mean level of this index and its dynamics during the experimental period. Rats of the strain with high excitability showed the rhythmical changes of taste sensitivity to PTC related to the phases of moon rhythm. The obtained evidence points to relation between the sign under study and individual characteristics of the nervous system, namely, its excitability, and suggests the differences in activity of the second messenger system (Ca++, c-AMP and others) in the studied rat strains.

Animals↗
PubMed1999

Gustometry of diabetes mellitus patients and obese patients.

The sensation of adequate taste detection can be associated with satisfaction of food intake. The impairment of taste detection may be associated with the development of obesity. Taste detection is determined hereditarily, but it can be influenced also by the occurrence of neuropathy. To find an explanation for these phenomena, we investigated 73 patients with diabetes mellitus (DM) 2 (i.e., non-insulin-dependent DM); 11 patients with DM 1 (i.e., insulin-dependent DM); 12 obese patients (body-mass index >30) without DM; and 29 control patients. All subjects underwent electrogustometric examination with Hortmman's electrogustometer. During this examination, we obtained electrical thresholds of taste by stimulating appropriate parts of the tongue. We stimulated the apex, middle, and near tongue radix areas on both sides. The resulting value is the average on the left and right sides of the mentioned areas. We considered a value of less than 40 microA to be normal. Values in excess of 100 microA are considered as hypogeusia. Values between 40 and 100 microA are taken as borderline, and ageusia is in excess of 500 microA. According to these criteria, in the DM 2 group, we found 40% of patients with hypogeusia, whereas in the DM 1 group, we found 33% of patients; 25% of patients were in the obese group. Among normal subjects (people without obesity or DM), no hypogeusia was found. We found ageusia in 5% of patients with DM 2, in 3% of patients with DM 1, and in 14% of obese patients. Among normal subjects, we found no ageusia. These results support the hypothesis that diminished taste detection can evoke hyperphagia and later obesity.

Adolescent↗
PubMed1975

Genetic variation in Nigeria. I. The genetics of phenylthiourea tasting ability.

Phenylthiourea (PTC) taste sensitivity thresholds have been measured for 2,013 Nigerians using a modified sorting technique. The frequency of non-tasters was observed to be 12.5% and the t gene frequency was 0.354. There was a significant difference between the sexes at the 0.01 level for the overall population. However, when the data are analyzed according to the geographical origin of the subject, the sex difference is found only in one of three geographical regions. Also, there may be geographical influences on PTC taste sensitivity, although this was not statistically significant. The estimates reported in this population differ considerably from some of the previously published estimates for black populations.

Adolescent↗
PubMed1985

Interrelationship of some selected nutritional parameters relevant to taste for salt in a group of college-aged women.

Students in a women's college were investigated for taste acuity for salt, discrimination of salt concentrations in food, and anthropometrical (the body mass index, and systolic and diastolic blood pressures) and biochemical nutritional parameters (blood hemoglobin, plasma zinc, plasma copper, plasma vitamin A, plasma retinol-binding protein, urinary sodium, urinary potassium, urinary magnesium, urinary calcium and urinary zinc). Among 95 students who participated in the test for discrimination of salt concentrations, which was repeated 6 times with 5 different test samples, only 43 (45.3%) committed no mistakes. The detection threshold for taste of salt was significantly associated with neither the discriminability of salt concentrations nor any biochemical parameters. Levels of plasma zinc (PZn), urinary zinc (UZn) and plasma vitamin A (VA) were lower in the present subjects than in those reported previously. The rate of correct discrimination (RCD) was significantly correlated with PZn and VA positively, and with urinary sodium (UNa) and urinary potassium (UK) negatively. In the factor analysis to investigate the interrelationship of nutritional parameters, 6 factors with significance were extracted, among which factors 3 and 4 were related to RCD. Factor 3 had large loadings on VA, plasma retinol-binding protein (RBP) and RCD, and factor 4 was positively loaded on UNa and UK and negatively on UZn and RCD. In the stepwise multiple regression analysis (RCD being the dependent variable), significant independent variables selected were VA, UK, PZn, systolic blood pressure and UNa. From these results, the college-aged women's failure in discriminating salt concentrations in food was likely to be related to vitamin A inadequacy, mild Zn deficiency and excessive intakes of Na and K.

Adolescent↗
PubMed1998

Influence of physical exercise on human preferences for various taste solutions.

The effects of physical exercise on preference for various sapid solutions was studied in 58 healthy university students. After 30 min of exercise using a bicycle ergometer at 50% VO2max (maximal oxygen uptake) intensity, a rating scale test on taste hedonic tone and the triangle test for taste absolute threshold were done. The test solutions were sucrose, NaCl, citric acid, caffeine and monosodium glutamate (MSG). Preference scale values for sucrose and citric acid increased after exercise, whereas the values for NaCl, caffeine and MSG were not changed. The absolute thresholds for all the sapid solutions did not differ for pre- and post-exercise. These findings indicate that in humans preference for sucrose and citric acid increase after physical exercise.

Adult↗
PubMed1981

Molecular mechanism of sweet taste: relationship of hydrogen bonding to taste sensitivity for both young and elderly.

Taste detection thresholds for 11 sweeteners varying widely in chemical structure were determined for young and elderly subjects. The rank orders of the thresholds for young and elderly were highly correlated (Spearman's rho=0.976) although the thresholds were 2.72 times higher on the average for the elderly when compared with the young. This decreased sensitivity was statistically highly significant, p=0.000266. Sweeteners with the lowest detection thresholds tended to have the greatest number of units (AH-B systems) capable of intermolecular hydrogen bonding. In addition, use of the method of magnitude estimation with 10 sweeteners revealed that the elderly perceived less growth in intensity with increasing concentration than young subjects. The slopes of the psychophysical functions relating concentration and perceived intensity were flatter in all cases for elderly subjects; the mean ratio, slope(young)/slope(elderly), was 2.06. The largest relative decline in slope was found for those stimuli with the greatest number of possible AH-B types, suggesting that the possibilities for concerted intermolecular hydrogen bonding may decline with age. If the elderly compensate for their diminished taste acuity with increased consumption, they may constitute a population with higher than average risk of any adverse dose-related biological effects of artificial sweeteners.

Adult↗
PubMed2003

Association between plasma zinc concentration and zinc kinetic parameters in premenopausal women.

The objective of this study was to measure relationships between plasma zinc (Zn) concentrations and Zn kinetic parameters and to measure relationships of Zn status with taste acuity, food frequency, and hair Zn in humans. The subjects were 33 premenopausal women not taking oral contraceptives and dietary supplements containing iron and Zn. Main outcomes were plasma Zn concentrations, Zn kinetic parameters based on the three-compartment mammillary model using 67Zn as a tracer, electrical taste detection thresholds, and food frequencies. Lower plasma Zn was significantly (P < 0.01) associated with smaller sizes of the central and the lesser peripheral Zn pools, faster disappearance of tracer from plasma, and higher transfer rate constants from the lesser peripheral pool to the central pool and from the central pool to the greater peripheral pool. The break points in the plasma Zn-Zn kinetics relationship were found between 9.94 and 11.5 micromol/l plasma Zn. Smaller size of the lesser peripheral pool was associated with lower frequency of beef consumption and higher frequency of bran breakfast cereal consumption. Hypozincemic women with plasma Zn <10.7 micromol/l or 700 ng/ml had decreased thresholds of electrical stimulation for gustatory nerves. Our results based on Zn kinetics support the conventional cutoff value of plasma Zn (10.7 micromol/l or 700 ng/ml) between normal and low Zn status.

Adolescent↗
PubMed1994

Influences on acceptance of bitter foods and beverages.

Bitterness is generally viewed as an undesirable attribute of foods and beverages, yet segments of the population regularly ingest items with a prominent bitter taste. The influence of taste sensitivity, exposure, selected personality traits (i.e., neophobia, variety seeking, sensation seeking) and pharmacological reactivity on alcohol and caffeine consumption, two widely consumed bitter substances, was assessed in 20 healthy adults (10 male, 10 female). Self-reported alcohol use was positively correlated with measured ethanol taste detection threshold and pharmacological reactivity (self-reported behavioral effects). The latter accounted for 23% of the variance in alcohol intake. Caffeine intake was significantly associated with personality traits. Sensation seeking status and self-reported reactivity to caffeine accounted for 46% of the variance in caffeine intake. Pleasantness ratings for novel bitter and sour foods were unaffected by 10 exposures whereas increased ratings were given to sweet and salty items. Variation in the influence of these factors between individuals and across products may explain individual differences in the acceptability and use of foods and beverages containing alcohol, caffeine and other bitter compounds.

Adult↗
PubMed1995

Gustatory detection thresholds after parabrachial nuclei lesions in rats.

Rats with either electrolytic (Experiment 1) or excitotoxic lesions (Experiment 2) that had been electrophysiologically centered in the gustatory zone of the parabrachial nuclei (PBN) were tested for sucrose and NaCl taste detection thresholds in a conditioned avoidance task. With 1 exception, all of these rats had previously shown severe deficits in acquiring an LiCl-based conditioned taste aversion (CTA) to sucrose, NaCl, or alanine. The rats with excitotoxic lesions also had failed to express a depletion-induced sodium appetite. Despite the uniformity of these deficits, the rats with lesions exhibited varied performance in the detectability task. Roughly 1/3 of the rats did not perform competently, 1/3 had elevated thresholds, and 1/3 showed no or only marginal impairments in taste detectability. These findings demonstrate that the elimination of CTA following PBN lesions is not necessarily linked to an impairment in taste signal detection. Thus, PBN-induced deficits on 1 taste-related task do not entirely correspond with impairments on another.

Animals↗
PubMed1991

Food intake, eating-related complaints, and smell and taste sensations in patients with cancer of the lung, ovary and breast undergoing chemotherapy.

Nutritional status and energy and protein intake were studied in 52 patients with cancer of the breast, ovary or lung before, after 1, and after 3 cycles of aggressive chemotherapy. Pre-treatment intakes were somewhat lower than recommended and did not change after 3 cycles of chemotherapy, neither did nutritional status. Many patients had eating-related complaints, but these complaints did not increase significantly with chemotherapeutic treatment. In 31 patients electrical taste detection thresholds and chemical smell detection thresholds were measured before and after 3 cycles of chemotherapy. Changes in thresholds had no relation to changes in energy and protein intake. Perceived taste and smell changes were not reflected in chemosensory threshold values.

Journal Article↗
PubMed1979

Age-related differences in salt taste acuity.

Salt taste detection thresholds were measured in 76 adults aged 23 to 92 years using a forced-choice staircase procedure, with distilled water rinses between all stimuli. Although an age-related decrease in salt taste acuity was observed, the decrement was smaller than previously reported in other studies. Past reports have probably exaggerated taste deficits in the elderly, because adequate rinse procedures and controls for subject response biases have not been incorporated in threshold measures.

Adult↗
PubMed1995

Detection of heteroquality taste mixtures.

Detection thresholds were measured for sweet (sucrose), salty (sodium chloride), sour (citric acid), and bitter (quinine hydrochloride) and for the 11 possible mixtures of these four substances. These 11 mixtures (6 binary, 4 ternary, and 1 quaternary) all turned out to be stimulus additive, in the sense that a person could reliably detect mixtures whose individual components are weaker than their unmixed thresholds. Tastants too weak to be perceived alone can thus make impact when in mixtures. The threshold concentration for a given compound was reduced in approximate proportion to the number of compounds added to it. This liberal heteroquality additivity contests the widespread belief that heteroquality mixtures (different chemicals evoking different qualities) are non-additive and homoquality mixtures (different chemicals evoking the same quality) are additive. Heteroquality additivity emerges on appropriate definition of the subject's task by forced choice (unavailable to earlier investigators), in order to skirt methodological pitfalls. Operating together, homo- and heteroquality additivity may concomitantly enable a person to sense natural mixtures of hosts of weak constituents, such as drinking water. In this regard, gustatory mixtures may function much as do mixtures of frequencies in audition and mixtures of gaseous compounds in olfaction.

Adolescent↗
PubMed1995

Perceptual properties of benzoic acid derivatives.

Sensory properties of equimolar concentrations of benzoic acid derivatives were examined using time-intensity procedures. Significant differences in maximum intensities (P < 0.005) were found for astringency, bitterness, prickling, sourness and sweetness. Although these compounds differed only in the number and position of the hydroxy groups, they exhibited quite different profiles. Gentisic acid had the highest sourness and bitterness maximum intensity, salicylic and gentisic acids were highest in astringency, and m-hydroxybenzoic acid was the sweetest sample. Benzoic acid had the highest intensity of prickling feeling which lasted 20 s longer than salicylic acid and 40 s longer than the other samples which elicited lowest intensity of prickling sensation.

Adult↗
PubMed1992

Alterations in taste acuity associated with allogeneic bone marrow transplantation.

Taste detection and recognition thresholds were monitored in 10 patients for up to 1 yr after allogeneic bone marrow transplantation (BMT). As well as a control group of 12 healthy volunteers, taste acuity was tested in 10 patients, who had undergone BMT 2-5 yr previously. Immediately after transplantation, there was significant hypogeusia of all four taste modalities compared to registrations one week before the aplastic phase and also compared to the healthy control group. Although some normalization of taste thresholds was registered 3-6 months after transplantation, most subjects still experienced dysgeusia. Of the four taste modalities, the most frequently recorded change was a raised threshold for salt. In about 80% of the patients taste acuity had recovered to the control values one year after transplantation. The group tested 2-5 yr after BMT had normal values for taste acuity.

Bone Marrow Transplantation↗
PubMed2004

Irradiation impairment of umami taste in patients with head and neck cancer.

BACKGROUND: Previous studies have reported the alteration of the four basic tastes (sweet, salty, sour and bitter) in patients with head and neck cancer (HNC) during radiotherapy. However, there has been no investigation on the function of umami taste, a novel basic taste recognized recently, during head and neck irradiation. OBJECTIVE: To investigate the recognition threshold of umami and the four basic tastes at different irradiation dose intervals during radiotherapy for head and neck cancer. METHODS: In 30 patients with malignant neoplasm of head and neck, objective taste thresholds were examined by use of a whole-mouth method at pre-radiotherapy, irradiation doses at 15, 30, 45, and 60 Gy, respectively. Subjective taste loss and some distresses were recorded simultaneously. RESULTS: Sweet, sour, salty, and bitter tastes showed temporarily and slightly increased thresholds during the treatment, but no statistical difference was found between the threshold at pre-radiotherapy and that at 15, 30, 45, and 60 Gy in any taste quality (all P > 0.05). Significantly impaired threshold of umami taste was revealed at 30 Gy (P < 0.05) and remained throughout the following treatment (at 45 and 60 Gy, both P < 0.01). Subjective taste impairment, appetite loss and satisfaction with the current state tended to deteriorate significantly during the irradiation. Mean body weight of the patients experienced a continuous loss, decreasing from an average of 60.4 kg before treatment to 57.3 kg at 60 Gy (P < 0.01). Scores of satisfaction with current state showed a significant correlation with umami taste thresholds (P = 0.035). CONCLUSION: The clinical impairment pattern of umami taste is different from that of the other four basic tastes in HNC patients during radiotherapy. Impaired umami taste acuity plays an important role in impacting the quality of life of the patients irradiated to the head and neck.

Head and Neck Neoplasms↗