Home screening of taste and oral trigeminal function: a feasibility study.

PURPOSE: gustatory ability is a marker of health not routinely tested in the medical practice. The current study wants to assess whether taste strips can be useful to monitor taste function from home. METHODS: we performed simple sensory tests in lab setting vs. unassisted testing at home, and compared the results with self-reports ability to taste and smell. Using paper strips impregnated with sweet, bitter, salty, or sour tastants, and with two trigeminal stimuli (capsaicin, tannins) in high and low concentrations, we assessed gustatory and trigeminal function in 74 participants (47 women) in the lab, where paper strips were administered by an experimenter, and in 77 participants (59 women) at home, where they self-administered the test. RESULTS: we found that high (but not low) concentration taste strips are correctly identified by vast majority of participants. On average, taste identification, intensity and pleasantness scores did not differ for the 8 taste strips, while identification of capsaicin was significantly better in the lab. Taste identification scores correlated with intensity ratings in both settings (r = 0.56, in the lab, r = 0.48, at home, p < 0.005). Self-rated taste ability correlated with self-rated smell ability (r = 0.68, and r = 0.39, p ≤ 0.005), but not with scores in the strips test. CONCLUSION: home testing with impregnated taste strips is feasible, and can be used for telemedical purposes.

Null cross-modal effects of olfactory training on visual, auditory or olfactory working memory in 6- to 9-year-old children.

Systematic exposure to odours (olfactory training, OT) is a method of smell loss treatment. Due to olfactory system projections to prefrontal brain areas, OT has been hypothesized to enhance cognitive functions, but its effects have been studied predominantly in adults. This study tested OT effects on working memory (WM), i.e., the ability to store and manipulate information for a short time, in healthy children aged 6-9 years. We expected OT to improve olfactory WM and establish cross-modal transfer to visual and auditory WM. Participants performed 12 weeks of bi-daily OT with either 4 odours (lemon, eucalyptus, rose, cloves; OT group) or odourless propylene glycol (placebo group). Pre- and post-training, participants' WM was measured utilizing odours (olfactory WM) or pictures (visual WM) and a word-span task (auditory WM). 84 children (40 girls) completed the study. The analyses revealed no changes in the WM performance following OT. The olfactory WM task was the most difficult for children, highlighting the need to include olfactory-related tasks in educational programmes to improve children's odour knowledge and memory, just as they learn about sounds and pictures. Further neuroimaging research is needed to fully understand the impact of OT on cognitive functions in children.

Olfactory training effects in children after mild traumatic brain injury.

OBJECTIVE: Mild traumatic brain injury (mTBI) might impair the sense of smell and cognitive functioning. Repeated, systematic exposure to odors, i.e., olfactory training (OT) has been proposed for treatment of olfactory dysfunctions, including post-traumatic smell loss. Additionally, OT has been shown to mitigate cognitive deterioration in older population and enhance selected cognitive functions in adults. We aimed to investigate olfactory and cognitive effects of OT in the pediatric population after mTBI, likely to exhibit cognitive and olfactory deficits. METHODS: Our study comprised 159 children after mTBI and healthy controls aged 6-16 years (M = 9.68 ± 2.78 years, 107 males), who performed 6-months-long OT with a set of 4 either high- or low-concentrated odors. Before and after OT we assessed olfactory functions, fluid intelligence, and executive functions. RESULTS: OT with low-concentrated odors increased olfactory sensitivity in children after mTBI. Regardless of health status, children who underwent OT with low-concentrated odors had higher fluid intelligence scores at post-training measurement, whereas scores of children performing OT with high-concentrated odors did not change. CONCLUSION: Our study suggests that OT with low-concentrated odors might accelerate rehabilitation of olfactory sensitivity in children after mTBI and support cognitive functions in the area of fluid intelligence regardless of head trauma.

Odor discrimination in children aged 4â12 years.

Olfaction is functional at birth and newborns use their sense of smell to navigate their environment. Yet, certain chemosensory abilities are subject to experience and develop with age. It has been argued that odor discrimination is a key ability enabling organisms to capture and distinguish odors occurring in the environment to further identify them and formulate a behavioral response. Yet, the development of odor discrimination abilities has been overlooked in the literature, with few attempts to investigate developmental changes in odor discrimination abilities independent of verbal abilities and olfactory experience. Here, building on these attempts, we propose a novel approach to studying the development of odor discrimination abilities by utilizing odor enantiomersâpairs of odorous molecules of identical chemical and physical features, but differing in optical activity. We hypothesized that discrimination of enantiomeric odor pairs in children and adolescents would be less prone to age effects than discrimination of pairs of common odors due to their encoding difficulty and their limited exposure in common olfactory experience. We examined olfactory discrimination abilities in children aged 4â12 years with regard to three common odor pairs and five enantiomeric odor pairs. The study protocol eliminated verbal and cognitive development bias, resulting in diminished age advantage of the older children in discrimination of enantiomers as compared to common odors.

q-Powders: a quick test for screening retronasal olfactory disorders with tasteless powders.

PURPOSE: To investigate the clinical utility of q-Powders-a retronasal identification screening test. METHODS: A total of 156 subjects (92 females, mean age: 54.5 years ± 17.3 years) completed a 3-item q-Powders retronasal identification test and a 16-items Sniffin' Sticks orthonasal identification test. We analyzed whether the q-Powders test could differentiate between subjects with normosmia and subjects with an olfactory disorder. RESULTS: Our data indicated that subjects with an olfactory disorder scored lower in the q-Powders test than subjects with normosmia. The analyses revealed q-Powders test sensitivity of 84% and a test specificity of 64.9% with a score of 2 points taken as a cutoff for olfactory disorders. CONCLUSION: The 3-item q-Powders retronasal test may be used for screening purposes in clinical research. LEVEL OF EVIDENCE: 4.

Olfactory training with Aromastics: olfactory and cognitive effects.

PURPOSE: The olfactory system can be successfully rehabilitated with regular, intermittent stimulation during multiple daily exposures to selected sets of odors, i.e., olfactory training (OT). OT has been repeatedly shown to be an effective tool of olfactory performance enhancement. Recent advancements in studies on OT suggest that its beneficial effects exceed olfaction and extend to specific cognitive tasks. So far, studies on OT provided compelling evidence for its effectiveness, but there is still a need to search for an optimal OT protocol. The present study examined whether increased frequency of OT leads to better outcomes in both olfactory and cognitive domains. METHOD: Fifty-five subjects (28 females; Mage = 58.2 ± 11.3 years; 26 patients with impaired olfaction) were randomly assigned to a standard (twice a day) or intense (four times a day) OT. Olfactory and cognitive measurements were taken before and after OT. RESULTS: OT performed twice a day was more effective in supporting olfactory rehabilitation and interventions targeted to verbal semantic fluency than OT performed four times a day, even more so in subjects with lower baseline scores. CONCLUSIONS: OT is effective in supporting olfactory rehabilitation and interventions targeted to verbal semantic fluency. However, it may be prone to a ceiling effect, being efficient in subjects presenting with lower baseline olfactory performance and lower verbal semantic fluency.

Sensory compensation beliefs among blind and sighted individuals.

The process of neural and behavioral reorganization following sensory loss is known as sensory compensation. Typically, it is believed that sensory loss is followed by increased acuity of the intact modalities. Indeed, many studies compared blind and sighted individuals' sensitivity of the intact sensory modalities. Yet, it remains poorly understood whether sensory compensation is reflected in the lay beliefs of those, whom it concerns. We examined whether blind and sighted individuals believe that their lack of vision is compensated by increased sensitivity of the intact senses. Study 1 (n = 63) aimed to compare the ratings of sensory sensitivity made by blind and sighted people. Participants rated the sensory sensitivity of a blind population in four modalities (i.e., olfaction, audition, gustation, touch) and compared it to the sensory sensitivity of a sighted population. In Study 2 (n = 191) participants rated their own sensory sensitivity in four modalities. Each participant referred to (1) people of the same sensory status and (2) people of the opposite sensory status. The level of global self-esteem was controlled to verify self-enhancing nature of these beliefs. The results of both studies showed that the beliefs about sensory compensation are shared by blind and sighted participants on group and on individual levels. The self-enhancement underpinning of these beliefs was most pronounced in gustatory sensitivity assessment. Psychological and medical consequences of sensory compensation beliefs are discussed.

The Importance of Intact Senses in Mating and Social Assessments Made by Deaf Individuals.

Social perception is a multimodal process involving vision and audition as central input sources for human social cognitive processes. However, it remains unclear how profoundly deaf people assess others in the context of mating and social interaction. The current study explored the relative importance of different sensory modalities (vision, smell, and touch) in assessments of opposite- and same-sex strangers. We focused on potential sensory compensation processes in mate selection (i.e., increased importance of the intact senses in forming impressions of an opposite-sex stranger as a potential partner). A total of 74 deaf individuals and 100 normally hearing controls were included in the study sample. We found diminished importance of vision and smell in deaf participants compared with controls for opposite- and same-sex strangers, and increased importance of touch for the assessment of same-sex strangers. The results suggested that deaf people rely less on visual and olfactory cues in mating and social assessments, highlighting a possible role of sign language in shaping interpersonal tactile experience in non-romantic relationships.

Olfactory training in 8-year-olds increases odour identification ability: a preliminary study.

Olfactory training (OT), smelling odours, twice per day for an extended period, can improve the olfactory function in adults. The aim of the current study was to investigate whether OT can improve the olfactory function of children aged 8 years old. Odour thresholds and odour identification ability were compared between two groups across three separate testing sessions (baseline, 6-week post-baseline, 12-week post-baseline). After the baseline test, the control group (n = 21) completed 6 weeks of bi-daily OT with odourless stimuli, whereas the experiment group (n = 20) completed 6 weeks of bi-daily OT, smelling four different odours (eucalyptus, lemon, clove, rose). A repeated measure analysis of variance was used to test for group differences across the three testing sessions. Six weeks after OT had been completed, participants in the experiment group demonstrated a significant increase in odour identification scores (9.95 to 11.20), compared to the control group who demonstrated no increase (10.48 to 10.48). No group differences in odour threshold ability were found.Conclusion: Six weeks of OT enhances odour identification ability, but not odour thresholds, in 8-year-old children. What is Known: • Smell loss and dysfunction are associated with negative health outcomes such as depression and increased risk of consuming contaminated food. • Olfactory training can improve sense of smell in adults. What is New: • Olfactory training improves odour identification ability in 8-year-olds. • Olfactory training does not appear to enhance odour acuity in 8-year-olds.

Digit ratio and hand grip strength are associated with male competition outcomes: A study among traditional populations of the Yali and Hadza.

OBJECTIVES: Indirect measures of physiological features, such as digit ratio and hand grip strength (HGS), are associated with the outcome of male competition activities. However, most of the studies were conducted in developed and industrialized societies. We tested the hypothesis that both digit ratio and HGS are associated with performance in male-specific activities in two traditional preindustrial societies: Yali and Hadza. METHODS: To measure masculine behavioral traits, we determined warriorship status (Yali; n = 49) and assessed hunting skills (Yali n = 47 and Hadza n = 49). We also assessed the digit ratio and HGS of each male. We conducted our analyses using the Bayesian approach. RESULTS: Bayesian regression models indicated that greater hand grip strength is associated with better hunting outcomes among Hadza males. We did not find a similar link for the Yali. We found anecdotal evidence for the link between left hand digit ratio and the number of birds hunted by Hadza. We found no evidence for the link between digit ratio and performance in male-male competition. CONCLUSIONS: Our results suggest that male-male competition outcomes are determined by upper body strength, but only in the Hadza population. We also found limited support for the hypothesis that digit ratio is associated with hunting success among the Hadza. We found no support for the hypothesis concerning the digit ratio or HGS among the Yali. Our research provides partial support for the evolutionary hypotheses based on studies conducted in industrialized populations.

Human height preferences as a function of population size in the Cook Islands and Norway.

OBJECTIVES: Height preferences and mating patterns related to body size vary across cultures yet it remains unclear why such between-population differences exist. Here, we test a hypothesis that nonrandom assortative mating is negative (mating with nonsimilar partners) in small isolated populations, and positive (mating with similar partners) in larger populations. METHODS: We compared preferences for sexual dimorphism in stature (SDS, male height/female height) among men and women living in small isolated communities (as few as 60 inhabitants) vs larger urban areas (as many as 70 000 inhabitants). To increase generalizability, data were collected from heterogeneous populations in the South Pacific (Rarotonga vs Palmerston, Cook Islands) and Northern Europe (capital city of Tromsø vs villages in the Troms County of Norway). RESULTS: Norwegians preferred a significantly larger difference in height between partners (median SDS ratio of 1.14) than did Cook Islanders (median SDS ratios of 1-1.04). Indeed, while 30% of Cook Island men and women preferred a partner of the exact same height, this preference was observed among less than 3% of Norwegian men and 7% of Norwegian women. Critically, distributions in SDS preferences did not differ by sex or population size. Thus, rural and urban dwellers within both countries showed similar positive assortative preferences for height, wherein own height explained up to 62% of the variability in preferred partner height. CONCLUSIONS: Our results do not support negative assortative preferences in small-scale communities, and further indicate that the "male-taller norm," while weaker among Cook Islanders than Europeans, is observed to some extent in the South Pacific.

Quality of Life in Patients With Olfactory Loss Is Better Predicted by Flavor Identification Than by Orthonasal Olfactory Function.

To date, most studies on the relationship between chemosensory performance and quality of life have focused on orthonasal measures of olfactory function. In the current investigation, we examined the predictive value of orthonasal and flavor identification indices of olfactory function on a wide spectrum of health and sociopsychological factors, including quality of life, life satisfaction, overall health, and depressive symptoms. Participants were 178 ENT patients (Mage = 58 ± 1), representing various causes of olfactory loss: idiopathic smell loss (n = 51; Mage = 63 ± 2), sinunasal disease (n = 27; Mage = 56 ± 3), head trauma (n = 33; Mage = 51 ± 2), and infections of the upper respiratory tract (n = 67; Mage = 59 ± 2). They completed self-report questionnaires and underwent olfactory testing using Sniffin' Sticks (orthonasal olfactory testing) and "Taste Powder" (intraorally applied flavors for retronasal olfactory testing, additionally inducing taste sensation). Data were analyzed with hierarchical regression models wherein the first step included subjects' sex, age, and orthonasal olfaction score. In the second step, we included the "Taste Powder" score. Tested models revealed that the first step was not significantly predicting variables of interest; however, there was an improvement of the model's predictive value when the "Taste Powder" score was added. Results of this study suggest that flavor identification significantly improves predictions of health and sociopsychological functioning of ENT patients with various etiologies.

Whose nose does not know? Demographical characterization of people unaware of anosmia.

PURPOSE: For functionally anosmic subjects, the sense of smell is basically useless in daily activities-they are unlikely to detect the threatening smell of rotten food, gas or smoke, or to enjoy the flavor of food or the smell of perfumes. Although this appears very distressing, functionally anosmic subjects in our sample seemed not to be aware or bothered with impaired olfaction and enrolled for the study targeted to people with a normal sense of smell. METHODS: In the large sample of 9139 subjects who declared themselves to have a normal sense of smell, we have retrospectively found a notable proportion of scores indicating functional anosmia. RESULTS: When we look at the overall Sniffin' Sticks score, 0.45% of the sample was functionally anosmic and this fraction increased to 3.4% when the identification score of 8 points and below was used. We present demographical information of those subjects, who despite their inability to use smell in daily life, consider themselves healthy. CONCLUSIONS: Data offer a new perspective on the importance of olfaction in daily life and supports the notion about the importance of using screening tools in clinical practice.

Fast Screening of Olfactory Function Using the Q-Sticks Test.

OBJECTIVES: Classical, longer olfactory tests are associated with difficulties in everyday practice. The aim of this study was to investigate the clinical utility of the Q-Sticks test within the context of a multicenter study. METHODS: A total of 333 subjects, aged between 12 and 88 years, completed a 3-item Q-Sticks test and a longer Sniffin' Sticks identification test. We analyzed the sensitivity and specificity of the test results for different cutoffs for anosmia and hyposmia. RESULTS: Our study showed that the test can be used on subjects aged 12 years and older, regardless of their sex. The data indicated a test sensitivity and specificity of 91.8 and 92%, respectively, with a score of 2 taken as a cutoff for olfactory dysfunction. Conversely, normal olfactory function can be declared with high probability with a score of 3 in the Q-Sticks test. CONCLUSION: We reconfirmed that the Q-Sticks test is a good screening tool for everyday medical practice and in laboratory settings, although it has to be kept in mind that the test can produce false-negative results at a score of 3. The test was relatively sensitive to anosmia and differences between normosmic and hyposmic/anosmic patients.

Voice pitch modulation in human mate choice.

Inter-individual differences in human fundamental frequency ( F0, perceived as voice pitch) predict mate quality and reproductive success, and affect listeners' social attributions. Although humans can readily and volitionally manipulate their vocal apparatus and resultant voice pitch, for instance, in the production of speech sounds and singing, little is known about whether humans exploit this capacity to adjust the non-verbal dimensions of their voices during social (including sexual) interactions. Here, we recorded full-length conversations of 30 adult men and women taking part in real speed-dating events and tested whether their voice pitch (mean, range and variability) changed with their personal mate choice preferences and the overall desirability of each dating partner. Within-individual analyses indicated that men lowered the minimum pitch of their voices when interacting with women who were overall highly desired by other men. Men also lowered their mean voice pitch on dates with women they selected as potential mates, particularly those who indicated a mutual preference (matches). Interestingly, although women spoke with a higher and more variable voice pitch towards men they selected as potential mates, women lowered both voice pitch parameters towards men who were most desired by other women and whom they also personally preferred. Between-individual analyses indicated that men in turn preferred women with lower-pitched voices, wherein women's minimum voice pitch explained up to 55% of the variance in men's mate preferences. These results, derived in an ecologically valid setting, show that individual- and group-level mate preferences can interact to affect vocal behaviour, and support the hypothesis that human voice modulation functions in non-verbal communication to elicit favourable judgements and behaviours from others, including potential mates.

A Compensatory Effect on Mate Selection? Importance of Auditory, Olfactory, and Tactile Cues in Partner Choice among Blind and Sighted Individuals.

Human attractiveness is a potent social variable, and people assess their potential partners based on input from a range of sensory modalities. Among all sensory cues, visual signals are typically considered to be the most important and most salient source of information. However, it remains unclear how people without sight assess others. In the current study, we explored the relative importance of sensory modalities other than vision (smell, touch, and audition) in the assessment of same- and opposite-sex strangers. We specifically focused on possible sensory compensation in mate selection, defined as enhanced importance of modalities other than vision among blind individuals in their choice of potential partners. Data were obtained from a total of 119 participants, of whom 78 were blind people aged between 16 and 65 years (M = 42.4, SD = 12.6; 38 females) and a control sample of 41 sighted people aged between 20 and 64. As hypothesized, we observed a compensatory effect of blindness on auditory perception. Our data indicate that visual impairment increases the importance of audition in different types of social assessments for both sexes and in mate choice for blind men.

Similarities in smell and taste preferences in couples increase with relationship duration.

Numerous studies point to partners' congruence in various domains and note an increase in their compatibility over time. However, none have explored a shift in chemosensory perception related to relationship duration. Here, we examined the relationship between the time heterosexual couples have spent together and the degree to which they share their gustatory and olfactory preferences. Additionally, we investigated whether these preferences are associated with relationship satisfaction. One-hundred couples aged from 18 to 68 years being together for a period between 3 and 540 months rated the pleasantness of a wide variety of olfactory and gustatory stimuli. We showed that both taste and smell preferences are more similar the longer couples have been in a relationship. We also observed a very interesting trend in terms of smell preferences, with relationship satisfaction being negatively related to congruence in smell preferences between partners. We discuss these results from the perspective of evolutionary psychology.

Effects of "trigeminal training" on trigeminal sensitivity and self-rated nasal patency.

PURPOSE: Patients with the feeling of a congested nose not always suffer from an anatomical obstruction but might just have a low trigeminal sensibility, which prevents them from perceiving the nasal airstream. We examined whether intermittent trigeminal stimulation increases sensitivity of the nasal trigeminal nerve and whether this effect is accompanied by subjective improvement of nasal breathing. METHOD: Thirty-five patients (Mage = 58.4 years; SD = 14.8; Minage = 21 years; Maxage = 79 years; 43% females) and 30 healthy controls (Mage = 36.7 years, SD = 14.5; Minage = 20 years; Maxage = 73 years; 60% females) participated in a study comprised of two sessions separated by "trigeminal training". During each session, trigeminal sensitivity towards CO2, trigeminal lateralization abilities and ratings of nasal patency were assessed. Age and training compliance were controlled. RESULTS: "Trigeminal training" had a positive effect on trigeminal sensitivity in both groups, (p = .027) and this effect depended on the training compliance (p < .001). "Trigeminal training" had no effect on lateralization abilities of the subjects (p > .05). Ratings of nasal patency increased in patients (p = .03), but not in controls. CONCLUSIONS: "Trigeminal training" consisting of intermittent presentation of diverse stimulants leads to an increase of trigeminal sensitivity, but this effect depended on the training compliance. Importantly, in patients, this training is also associated with an increase in self-rated nasal patency.

Can blind persons accurately assess body size from the voice?

Vocal tract resonances provide reliable information about a speaker's body size that human listeners use for biosocial judgements as well as speech recognition. Although humans can accurately assess men's relative body size from the voice alone, how this ability is acquired remains unknown. In this study, we test the prediction that accurate voice-based size estimation is possible without prior audiovisual experience linking low frequencies to large bodies. Ninety-one healthy congenitally or early blind, late blind and sighted adults (aged 20-65) participated in the study. On the basis of vowel sounds alone, participants assessed the relative body sizes of male pairs of varying heights. Accuracy of voice-based body size assessments significantly exceeded chance and did not differ among participants who were sighted, or congenitally blind or who had lost their sight later in life. Accuracy increased significantly with relative differences in physical height between men, suggesting that both blind and sighted participants used reliable vocal cues to size (i.e. vocal tract resonances). Our findings demonstrate that prior visual experience is not necessary for accurate body size estimation. This capacity, integral to both nonverbal communication and speech perception, may be present at birth or may generalize from broader cross-modal correspondences.

Development of the Arabic version of the "Sniffin' Sticks" odor identification test.

UNLABELLED: Sniffin' Sticks Test (SST) is a comprehensive tool for medical or scientific diagnosis of olfactory sensitivity. Although it is widely used around the world, it is recommended to develop a cultural adaptation of any odor identification test prior to using it in a particular cultural space. The aim of the present work is to adapt SST to Arabic population, running experiments in Egypt. Prospective controlled study. We included 382 people (174 women and 208 men) aged 8-74 years; 323 healthy subjects and 59 patients. The use of original list of odors revealed that four of the descriptors were poorly recognized (<75 %) in Egypt. Accompanied by several control measurements descriptors and targets were replaced with more familiar names. The result of the present study is a modified version of the original SST, adapted to the Arabian space with a high test-re-test reliability. In addition, first tentative normative data are presented for the Arabic population. The 10th percentile for the whole group of healthy subjects equaled 13, whereas in 16-35 age category it equaled 14. The revised SST test can be used in studies on olfactory sensitivity in Arabic populations. LEVEL OF EVIDENCE: 2b.