Does sweetness exposure drive 'sweet tooth'?

It is widely believed that exposure to sweetened foods and beverages stimulates the liking and desire for sweetness. Here we provide an updated review of the empirical evidence from human research examining whether exposure to sweet foods or beverages influences subsequent general liking for sweetness ('sweet tooth'), based on the conclusions of existing systematic reviews and more recent research identified from a structured search of literature. Prior reviews have concluded that the evidence for a relationship between sweet taste exposure and measures of sweet taste liking is equivocal, and more recent primary research generally does not support the view that exposure drives increased liking for sweetness, in adults or children. In intervention trials using a range of designs, acute exposure to sweetness usually has the opposite effect (reducing subsequent liking and desire for sweet taste), while sustained exposures have no significant effects or inconsistent effects. Recent longitudinal observational studies in infants and children also report no significant associations between exposures to sweet foods and beverages with measures of sweet taste preferences. Overall, while it is widely assumed that exposure to sweetness stimulates a greater liking and desire for sweetness, this is not borne out by the balance of empirical evidence. While new research may provide a more robust evidence base, there are also a number of methodological, biological and behavioural considerations that may underpin the apparent absence of a positive relationship between sweetness exposure and liking.

Children's liking for vegetarian and non-vegetarian school meals at the scale of a French city.

In Western countries, a behavioural shift towards more plant-based diets is helpful in protecting population and planet health. School canteens are an important public policy target to achieve this transition. Increasing the frequency of vegetarian meals in school canteens has been proposed as a solution to decrease greenhouse gas emissions while maintaining a good nutritional quality. However, vegetarian meals acceptance by children is key to limit unintended consequences such as increased food waste or increased nutritional inequalities. We aimed to examine children's liking for vegetarian and non-vegetarian main dishes at school canteens; and whether it varied across socioeconomic level. Connected scoring devices displaying a five-point smiley scale were installed in all the 38 primary school canteens of a French city, located in socially diverse neighbourhoods. Every day after their school lunch, children were asked to rate the main dish they had just eaten. During one school year, from September 2021 to June 2022, we collected 208,985 votes for 125 main dishes, including 32 vegetarian (i.e., no meat or fish) and 93 non-vegetarian dishes, for an average of 1672 (SD 440) votes per day across the 38 school canteens. We showed no difference in children's liking for vegetarian and non-vegetarian dishes. Additionally, the socioeconomic level of the schools was found to interact negatively with children's liking for vegetarian main dishes whereby vegetarian main dishes tended to be more liked in schools of lower socioeconomic level. In this French city, children's acceptance would not be a barrier to increase the frequency of vegetarian school meals and would not increase social dietary inequalities.

Self-reported food liking and wanting: A factor analytic study of ratings across 49 consecutive days.

Reward responses to food are thought to play an important role in highly palatable food overconsumption. In animal models, food reward responses can be decoupled into unique "liking" (in the moment enjoyment) and "wanting" (motivation/craving) components. However, research on liking and wanting has been hampered by uncertainty regarding whether liking and wanting can be reliably separated in humans. We used factor analysis to test whether ratings of liking and wanting could be empirically separated in women assessed across 49 consecutive days. Female participants (N = 688; ages 15-30) from the Michigan State University Twin Registry reported liking and wanting of foods consumed that day, and wanting of foods not consumed that day, separately for sweets (e.g., cookies), fast food (e.g., French fries), carbohydrates (e.g., bread), and whole foods (fruit, plain chicken) each evening for 49 consecutive days. We examined both average levels and daily levels of liking/wanting across the 49-day period that captured individual differences in liking/wanting over time. Across both types of analyses, liking and wanting for foods that were eaten formed a single factor rather than separate, dissociable factors, while wanting of foods not eaten formed an independent factor. At the daily level, a liking/wanting factor emerged for each individual food category (e.g., liking/wanting sweets), whereas in average analyses, a single factor emerged that collapsed across all food types (i.e., liking/wanting of all foods). Results suggest individuals have difficulty distinguishing between liking and wanting of foods they have eaten on that day but may be able to more reliably separate wanting of foods they have not consumed.

Meat- and plant-based products induced similar satiation which was not affected by multimodal augmentation.

Little is known about how plant-based products influence satiation compared to corresponding meat-based products. As augmented reality (AR) intensifies sensory experiences, it was hypothesized to improve satiation. This study compared satiation between intake of meatballs and plant-based balls and plant-based balls intensified with AR for visual, olfactory, and haptic sensory properties. Intake order of the meatballs, plant-based balls, and augmented plant-based balls, eaten on separate days, was randomized. Satiation was measured from twenty-eight non-obese adults as ad libitum intake of the balls and extra snacks, and as subjective appetite sensations. Liking and wanting to eat the products were also investigated. There were no differences between the products in satiation. Before tasting the augmented plant-based balls were less liked than the meatballs (p = 0.002) or plant-based balls (p = 0.046), but after eating the first ball or eating the ad libitum number of balls the differences in liking disappeared. Wanting evaluations were similar for each product and decreased during eating (p < 0.001). A group of participants susceptible to AR was found (n = 11), described by decreased intake when augmentation was applied. Among the sub-group, wanting to eat the augmented balls was lower before tasting (p = 0.019) and after eating the first ball (p = 0.002) and appetite was less suppressed after eating the balls ad libitum (p = 0.01), when compared to non-susceptible participants. We conclude that meatballs and plant-based balls were equal in inducing satiation, and multisensory augmentation did not influence satiation. However, the augmentation decreased liking evaluations before tasting. Further studies are needed to explore differences between consumer groups in susceptibility to augmentation.

Does vaping affect the taste and smell perception? An exploratory study with New Zealand young adults.

OBJECTIVE: The study aimed to assess potential effects of vaping on individual taste and smell perception in a sample of young adult New Zealanders. DESIGN: This cross-sectional study measured taste and smell perception using intensity and hedonic ratings to two olfactory (i.e., vanillin, methional) and two gustatory stimuli (i.e., sucrose, monosodium glutamate), representing sweet and savoury flavours. Detection sensitivities to sucrose and vanillin were also assessed using a forced choice detection paradigm aligned with the signal detection framework. MANCOVAs were employed to compare sensory perception between groups based on vaping use frequency. Additional regression analyses were conducted to identify potential predictors of intensity and hedonic sensory ratings. SETTING: Participants were recruited from the University of Otago student population and surrounding neighbourhoods of Dunedin, New Zealand in 2023. PARTICIPANTS: The study included 213 university students (98 vapers and 115 non-vapers) RESULTS: We found a significant difference in hedonic ratings for vanillin, indicating a stronger preference among non-vapers. However, no other differences between the two groups were significant. Notably, the use of tobacco and mint flavours were emerged as significant predictors for hedonic responses to the savoury smell and sweet taste stimulus, respectively. No significant differences were observed between groups in the ability to detect weak stimuli. CONCLUSIONS: Our findings suggest that vape use, particularly with specific flavours, may be associated with alterations in hedonic responses to smells. This finding may have potential implications for how vaping affects on food preferences and dietary choices.

Sweet and sour sips: No effect of repeated exposure to sweet or sour-tasting sugary drinks on children's sweetness preference and liking.

Health agencies advocate reducing children's sweetness exposure to lower sweetness preference or liking to ultimately lower sugar intake. However, the relationship between sweetness exposure, preference, and liking remains unclear. This work investigated the influence of exposure to a sucrose-containing sweet or sour-tasting drink on sweetness preference and liking for sweet and sour products in 4-7-year-old children (n = 65). The children were randomized into three groups with one daily exposure to either the sweet drink, sour drink, or water (control group) for 14 days. Sweetness preference was assessed at baseline (t1), day 15 (t2), and two months after the intervention (t3), using a forced-choice, paired comparison test with five beverages varying in sweetness intensity. Hedonic liking for the intervention drinks, a sweet and sour yogurt, and a sweet and sour candy was evaluated using a 5-point pictorial scale. Linear mixed models revealed a significant increase in sweetness preference from t1 to t3 (F(2) = 7.46, p < 0.001). However, ANCOVA analysis indicated that this effect was not caused by the intervention. Based on linear mixed models, we observed that children's hedonic liking for sweet and sour products remained stable from t1 to t3 and was not influenced by the intervention. These findings suggest that 14 exposures to a sucrose-containing sweet or sour-tasting drink did not affect sweetness preference or liking in 4-7-year-old children.

What's cooking, if not meat? Effects of repeated home-use, recipe inspiration and meal context on perception of plant-based meat analogues.

Plant-based meat analogues (PBMA) may help consumers in shifting towards more plant-based diets, but PBMA are not widely used yet, and little is known about their longer-term acceptance. This study investigated whether consumer acceptance of PBMA changed with repeated home-use, and whether providing recipe suggestions in the form of meal boxes could influence PBMA acceptance. To this end, Dutch regular meat eaters (n = 61) prepared, consumed and evaluated two meals (one from a meal box, one self-created) with PBMA (PB mince and PB chicken, counterbalanced across meal types) per week at home for four weeks. As a secondary objective, potential longer-term effects of repeated home-use of PBMA on meat (analogue) consumption habits and attitudes (e.g. motives for choosing PBMA, attitudes toward eating less meat) were assessed in a pre-vs post-intervention survey. Responses were compared with a control group of consumers not participating in the home-use study (n = 179). Results provided no evidence that PBMA liking changed with repeated home-use, nor that the provision of meal boxes increased liking of PBMA. Instead, PBMA liking was strongly influenced by the meal context, which may have overruled potential effects of repeated exposure. Findings from the pre- vs. post-intervention survey suggest that repeated exposure may stimulate longer-term consumption of PBMA, although more seems needed to bring about a structural shift toward a less animal-based consumption pattern. Future research should investigate whether more sophisticated recipes that provide a suitable meal context for PBMA and elevate consumers' meal experiences may improve PBMA acceptance and facilitate the transition toward more sustainable diets.

Evidence that carbohydrate-to-fat ratio and taste, but not energy density or NOVA level of processing, are determinants of food liking and food reward.

This virtual (online) study tested the common but largely untested assumptions that food energy density, level of processing (NOVA categories), and carbohydrate-to-fat (CF) ratio are key determinants of food reward. Individual participants (224 women and men, mean age 35 y, 53% with healthy weight, 43% with overweight or obesity) were randomised to one of three, within-subjects, study arms: energy density (32 foods), or level of processing (24 foods), or CF ratio (24 foods). They rated the foods for taste pleasantness (liking), desire to eat (food reward), and sweetness, saltiness, and flavour intensity (for analysis averaged as taste intensity). Against our hypotheses, there was not a positive relationship between liking or food reward and either energy density or level of processing. As hypothesised, foods combining more equal energy amounts of carbohydrate and fat (combo foods), and foods tasting more intense, scored higher on both liking and food reward. Further results were that CF ratio, taste intensity, and food fibre content (negatively), independent of energy density, accounted for 56% and 43% of the variance in liking and food reward, respectively. We interpret the results for CF ratio and fibre in terms of food energy-to-satiety ratio (ESR), where ESR for combo foods is high, and ESR for high-fibre foods is low. We suggest that the metric of ESR should be considered when designing future studies of effects of food composition on food reward, preference, and intake.

Nutrient clustering, NOVA classification, and nutrient profiling: How do they overlap, and what do they predict about food palatability?

We compared the performance of three food categorisation metrics in predicting palatability (taste pleasantness) using a dataset of 52 foods, each rated virtually (online) by 72-224 participants familiar with the foods in question, as described in Appetite 193 (2024) 107124. The metrics were nutrient clustering, NOVA, and nutrient profiling. The first two of these metrics were developed to identify, respectively: 'hyper-palatable' foods (HPFs); and ultra-processed foods (UPFs), which are claimed to be 'made to be hyper-palatable'. The third metric categorises foods as high fat, sugar, salt (HFSS) foods versus non-HFSS foods. There were overlaps, but also significant differences, in categorisation of the foods by the three metrics: of the 52 foods, 35 (67%) were categorised as HPF, and/or UPF, and/or HFSS, and 17 (33%) were categorised as none of these. There was no significant difference in measured palatability between HPFs and non-HPFs, nor between UPFs and non-UPFs (p ≥ 0.412). HFSS foods were significantly more palatable than non-HFSS foods (p = 0.049). None of the metrics significantly predicted food reward (desire to eat). These results do not support the use of hypothetical combinations of food ingredients as proxies for palatability, as done explicitly by the nutrient clustering and NOVA metrics. To discover what aspects of food composition predict palatability requires measuring the palatability of a wide range of foods that differ in composition, as we do here.

Exploring within-meal variety to promote appeal of home-cooked meals in older adults.

Undernutrition is highly prevalent in older adults and poses a major threat to physical and mental wellbeing. To foster healthy eating (and healthy aging), strategies are needed to improve dietary quality of older adults. In this study, the feasibility of increasing food variety in home-cooked meals is explored as strategy to promote meat and vegetable consumption in community dwelling older adults. Adults aged 50 years or older (N = 253) evaluated pictures of traditional Dutch dinner meals with more or less variety in the vegetable or meat component in an online questionnaire. Specifically, four different variety 'levels' were presented: (1) no variety, (2) meat variety, (3) vegetable variety, and (4) variety in both meat and vegetables (mixed). Participants indicated for each meal picture how much they would like the meal, whether it represented an ideal portion size, and whether they would be able and willing to prepare the meal. We expected that with increasing variety, liking and ideal portion size would increase, while ability and willingness to prepare the meals would decrease. Results showed that the meals with meat variety and mixed variety were liked less than meals with vegetable variety or no variety. Participants were all highly willing to prepare the meals, but they were less willing to prepare the meals with meat variety and mixed variety compared to the meals with vegetable variety and no variety. All meals were evaluated as being too large, but the meals with vegetable variety and mixed variety were evaluated as more oversized than the meals without variety and with meat variety. These results suggest that encouraging older adults to include variety in home-cooked meals might be more challenging than anticipated.

Application of multiple-intake temporal check all that apply: a case study of strawberry yoghurt formulated with alternative sweeteners.

BACKGROUND: It is crucial to reduce the high sugar content of fruit yoghurts in response to the excessive weight gain epidemic. The use of alternative sweeteners in yoghurts is often associated with the negative sensory attributes that can have an impact on yoghurt liking. The main objective of this research was to investigate the effect of alternative sweeteners and strawberry puree addition on the temporal sensory profile of yoghurt using multiple-intake temporal check all that apply (TCATA). A novel approach to the statical analysis of the temporal sensory data was employed by using aligned rank transformation-analysis of variance to investigate the differences between sensory attributes within different products and within different intakes. RESULTS: Results showed that the attributes sweet and fruity decreased when the concentration of fruit puree was increased at low concentration of sucrose. Interestingly, when the concentration of fruit puree was increased, fruitiness increased and mouthcoating decreased at low concentration of stevia. With successive intakes, the attributes sweet, sour, creamy and fruity significantly decreased in yoghurts sweetened with sucrose, xylitol and stevia. Yoghurts containing low concentrations of sucrose or xylitol and fruit puree were liked the most. However, stevia-sweetened yoghurts varying in sweetener and puree concentration were not significantly different in liking. In order to investigate the consumer acceptance of yoghurts, a novel approach was used - that is, utilizing TCATA temporal data to investigate temporal drivers of liking for each yoghurt type. CONCLUSION: The use of multiple statistical analysis to analyse temporal data suggested that both sweetener and puree concentration need to be considered when developing products using alternative sweeteners. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Consumption of edible insects and insect-based foods: A systematic review of sensory properties and evoked emotional response.

Low consumer acceptance of edible insects and insect-based products is one of the main barriers to the successful implementation of entomophagy in Western countries. This rejection is mainly caused by consumers' negative emotional responses, psychological/personality traits, and attitudes toward food choices. However, as the role of intrinsic product characteristics on such food choices has not been adequately studied, a systematic review was conducted following the PRISMA method, to analyze studies that have assessed hedonic evaluations, sensory profiling, or emotional responses to edible insects or insect-based products. The majority of studies performed with whole insects and insect flour highlight that insect-based products are more negatively evaluated than control products. Although the sensory properties of insects are affected by species and processing conditions, they are generally negative across sensory dimensions. In particular, insects and insect-based products are generally associated with odor and flavor/taste attributes that are related to old/spoiled food. These negative attributes can be linked to the fat fraction of edible insects, with insect oils being very negatively evaluated by consumers. On the other hand, defatted fractions and deodorized oils are not associated with these negative attributes, further supporting the hypothesis that the fat fraction is responsible for the negative odor and flavor/taste attributes. However, there is still a lack of studies assessing the sensory profile of edible insects and insect-based products, as well as consumers' emotional responses to their consumption. Future studies should focus on the effects of different processing conditions, products incorporating insect fractions (namely protein concentrates/isolates and defatted fractions), and evaluation by target consumer groups.

Trusting strangers: The benefits of reciprocal self-disclosure during online computer-mediated communication and mediating role of interpersonal liking.

Reciprocal self-disclosure has reportedly been associated with increased interpersonal trust. However, existing research mainly focuses on online disclosure between acquaintances and overlooks the types of reciprocal disclosure, especially in the initial interactions between strangers communicating online. This study aimed to investigate how three types of reciprocal self-disclosure (turn-taking reciprocity, extended reciprocity and non-reciprocity) contribute to trust and the mechanism of positive interpersonal liking, and whether any effect was instant and stable or increased across two interactions during computer-mediated communication (CMC). Participants were assigned to one of the three reciprocal disclosure conditions and engaged in online interactions. Self-reported and behavioural results demonstrated higher levels of interpersonal trust and liking in the second interaction phase than in the first across all conditions. The turn-taking reciprocity condition showed higher interpersonal trust than did the extended condition, and higher interpersonal liking than did the extended and non-reciprocity conditions; this effect was apparent in both interactions. These findings help us understand the relationship between online self-disclosure and interpersonal trust, suggesting that certain patterns of communication with strangers (e.g., turn-taking reciprocity) may foster more positive social outcomes during CMC over time, while demonstrating the importance of immediacy in synchronous conversations.

On How to Be Liked in First Encounters: The Effects of Agentic and Communal Behaviors on Popularity and Unique Liking.

When meeting other people for the first time, how should one behave in order to be liked? We investigated the effects of agentic and communal behaviors on two forms of being liked: popularity (being generally liked by others) and unique liking (being uniquely liked by specific interaction partners). In a round-robin study, 139 unacquainted German adults had dyadic conversations and provided liking ratings afterward. The conversations were recorded on video, and four agentic behaviors (leading, dominant, confident, boastful) and four communal behaviors (polite, benevolent, warm, friendly) were each rated by trained observers. Participants who generally showed agentic and communal behavior were also generally liked (popularity). When participants' level of communal, but not agentic, behavior exceeded their personal standards during an interaction, they were particularly well-liked by the respective interaction partner (unique liking). The behavioral predictors of being liked thus differ, depending on whether one focuses on popularity or unique liking.

Why do owls have it worse? Mediating role of self-perceptions in the links between diurnal preference and features of mental health.

Recent research provides evidence for the negative social perceptions of evening chronotypes and their consequences on mental health. However, there is a lack of studies indicating whether these negative, socially shared beliefs may become internalized in negative self-perceptions of evening-types (E-types). The present article provides a seminal empirical analysis of the role of self-liking and self-competence in the associations between chronotype and both depressiveness and well-being. In the first part of the study, the participants completed the Composite Scale of Morningness. On the basis of the chronotype cut-off criteria for Composite Scale of Morningness distribution, 100 individuals were classified as morning-types (M-types) and 66 individuals as E-types. Therefore, 166 participants (80 women and 86 men) aged 18-36 years (M ± SD: 29.27 ± 4.81 years) took part in the second part of the study, and completed questionnaires measuring self-liking, self-competence, life satisfaction, positive and negative affect, and depressiveness. Results show that E-types scored lower in self-liking, self-competence and subjective well-being, and higher in depressive symptoms than M-types. Controlling for age and gender, we obtained significant mediation effects, showing that the relationship between chronotype and subjective well-being might stem from the lower levels of self-liking and self-competence among E-types, and that the relationship between chronotype and depressive symptoms might stem from the lower level of self-liking among E-types. Our results suggest that self-liking and self-competence are important antecedents of lower well-being and higher depressiveness reported by E-types. Socially shared stereotypes of M-types and E-types can be internalized by the extreme chronotypes, which may significantly affect their psychological health.

Alterations in sweet taste function in adults with diabetes mellitus: a systematic review and potential implications.

Diet therapy for diabetes involves controlling carbohydrate intake in order to manage blood glucose concentrations. Simple carbohydrates, like sucrose, quickly and potently raise blood glucose when ingested, and are typically perceived as sweet. Sweetness is innately pleasurable and contributes to the positive hedonic evaluation of foods and beverages. There is some evidence to suggest that individuals with diabetes mellitus may be less able to detect sweetness, which could result in increased intake and, thus, more difficulty managing blood glucose. A systematic review that included PubMed, PsycInfo, and Embase databases was conducted. Inclusion criteria included observational studies that investigated the sweet taste function of adults with and without diabetes mellitus (Prospero CRD42021225058). The quality of the final included studies was assessed using the Academy of Nutrition and Dietetics' Evidence Analysis Library Quality Criteria Checklist: Primary Research tool. Eighteen studies that compared sweet taste thresholds, intensity ratings, or hedonic responses in adults both with and without diabetes were included. Differences in sweet taste thresholds, both detection and recognition, indicated that individuals with diabetes were less sensitive than healthy controls. The same findings were observed for intensity ratings. Only two studies examined hedonic responses; results were inconclusive.

A narrative review on food neophobia throughout the lifespan: relationships with dietary behaviours and interventions to reduce it.

Food neophobia is defined as the unwillingness to taste new foods and the avoidance of unfamiliar foods. This eating behaviour is a complex issue, and both genetic and environmental factors play a role in it. The aim of this review is to understand its relationships with dietary behaviours throughout the lifespan and to examine the impact of interventions on food neophobia. A literature search was performed using the PubMed, Web of Science, Cochrane Library and ScienceDirect databases. As a result of the screening, a total of 139 studies, seven of which were intervention studies, were included in this review. According to current evidence, food neophobia is negatively associated with the acceptance of not only novel/unfamiliar foods but also familiar foods. Many studies have shown that food neophobia is negatively associated with the hedonics and consumption of core foods, especially vegetables and fruits. Individuals with higher levels of food neophobia are less familiar with many foods, but familiarity is a prominent motivator in food choices for these individuals. Therefore, it may be considered a barrier limiting diet quality and this trend is similar for both children and adults. However, food neophobia is not an unchangeable personality trait. Intervention studies have pointed out that educational programmes and food-related activities that increase familiarity and exposure to foods and create positive attitudes towards and positive experiences with foods can reduce food neophobia. The results highlight that people with high food neophobia need more support to improve their diets and the quality of dietary behaviour.

A mechanistic staging model of reward processing alterations in individuals with binge-type eating disorders.

Altered reward processing is thought to characterize binge-type eating disorders, but the exact nature of these alterations is unclear. A more fine-grained understanding of whether specific aspects of reward processing contribute to the development or maintenance of binge eating may point to new therapeutic targets and personalized treatments. The incentive sensitization theory of addiction proposes that repeated use of a substance increases the desire to approach a reward ('wanting') but not pleasure when consuming the reward ('liking'), suggesting that reward processes driving addiction change over time. We hypothesize that the same may be true for binge eating. Further, consistent with the maladaptive scaling hypothesis, reward processing may be heightened for multiple reinforcers in at-risk individuals but become tuned toward food once binge eating is initiated. In this article, we propose a mechanistic staging model of reward processing in binge-type eating disorders that synthesizes existing data and posits that alterations of reward processing depend on illness stage and reward type. We outline translational methods for testing key hypotheses and discuss clinical implications. Considering reward processing alterations in relation to illness stage has the potential to improve treatment outcomes by ensuring that the mechanisms targeted are personalized to the individual patient. PUBLIC SIGNIFICANCE: Individuals with binge-type eating disorders experience alterations in their desire for, and pleasure from, food. We believe that the exact nature of these alterations in reward processing change over the course of illness-from the at-risk state to an established illness. If true, treatments for binge-type eating disorders that target reward processing should be personalized to the illness stage of the patient.

Observation and assessment of the immediate use of a silicon hydrogel contact lens after transepithelial corneal cross linking: a prospective study.

BACKGROUND: Transepithelial corneal crosslinking (CXL) is a novel surgical approach for the treatment of keratoconus, which is a bilateral asymmetrical ophthalmological disease accompanied by progressive corneal ectasia. Silicon hydrogel (SiH) contact lenses have been extensively used in clinical ophthalmologic medicine, as a postoperative ophthalmological intervention. However, the ideal lens application duration after transepithelial CXL remains uncertain. Here, we aimed to investigate the effects and comfort of immediate corneal contact lens use after transepithelial CXL for keratoconus. METHODS: In this prospective study, 60 patients with keratoconus who underwent transepithelial CXL treatment were enrolled from September 2021 to January 2023 with a male:female ratio of 39:21, and an average age of 25.42 ± 5.47 years. The patients were divided randomly into two groups: group A contained 30 patients wearing silicone hydrogel contact lenses for 7 days postoperatively, and group B contained 30 patients wearing the same contact lenses for 3 days. Ten subjective ophthalmologic symptoms were surveyed by the patients, including pain, photophobia, foreign body sensation, tearing, burning, blurred vision, dry eyes, difficulty opening the eyes, astringency, and stinging. Ophthalmologic signs, including corneal edema and conjunctival congestion, were recorded by a single clinician on postoperative days 1, 3, and 7. RESULTS: Each surgical procedure was readily performed without complications, and both groups postoperative day 7 (P = 0.04), where group B scored (0.01 ± 0.41) lesser than group A (0.12 ± 0.29), whilst corneal edema in both groups recorded significantly different on postoperative days 5 and 7 (group A demonstrated the result of 0.17 ± 0.14 and 0.08 ± 0.11 for the respective days, whereas group B indicated 0.10 ± 0.13 and 0.03 ± 0.07 at the corresponding times). CONCLUSIONS: Immediate use of silicone hydrogel corneal lenses after transepithelial CXL effectively alleviates postoperative ocular distress, particularly with a three-day use period as the ideal duration.

Predictors of state-based changes in wanting and liking.

People report wanting food when they are hungry, and on eating it they typically report liking the experience. After eating, both wanting and liking decline, but wanting declines to a greater extent, which we term the 'affective discrepancy effect'. In this study we examine the predictors - state, sensory and memory-based - of these affective changes. Hungry participants undertook three tasks: (1) written recollections of what certain foods are like to eat; (2) ratings of wanting and expected flavour liking and fillingness when looking at snacks, and ratings of food and flavour liking when eating them; (3) ratings of bodily state. These tasks were then repeated after lunch. State-based changes in food liking were best predicted by changes in flavour liking. For state-based change in wanting, memory-based information about flavour liking and fillingness from tasks (1) and (2) were all significant predictors. For recollections about eating (task 1), mentions of food fillingness significantly increased pre-to post-lunch and this was the best predictor of the affective discrepancy effect. Recollections of food fillingness are state-dependent, and can arise unbidden (i.e., such recollective content was unprompted). This may reflect one way that memory may selectively influence wanting, and hence whether food intake is initiated or not.