Social and environmental determinants, household food insecurity

Food security is defined as a situation that exists when “all people, at all times, have physical and economic access to sufficient, safe and nutritious food to maintain a healthy and active life. It is a multilevel concept, which includes four main dimensions: availability related to food supply; accessibility in order to ensure the physical and economic access to food; adequacy to meet nutritional needs in quantity and quality while respecting individual food preferences and cultural issues (utilization); and, lastly, stability of the guarantee of food security over time. According to the food security definition, it is abroad concept where all these dimensions are largely affected by a considerable number of factors related to: public policies of different sectors, food production/industry/distribution food systems, marketing and advertising of food, social support networks and individual determinants related to food choice behaviour.

An assessment of the potential of family day care as a nutrition promotion setting in South Australia

Articles > Journals > Health journals > Nutrition & Dietetics: The Journal of the Dieticians Association of Australia articles > March 2003 Article: An assessment of the potential of Family Day Care as a nutrition promotion setting in South Australia. (Original Research). Article from:Nutrition & Dietetics: The Journal of the Dieticians Association of Australia Article date:March 1, 2003 Author:Daniels, Lynne A.; Franco, Bunny; McWhinnie, Julie-Anne CopyrightCOPYRIGHT 2006 Dietitians Association of Australia. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights or concerns about this content should be directed to customer service. (Hide copyright information) Related articles Ads by Google TAFE Child Care Courses Government accredited courses. Study anytime, anywhere. www.seeklearning.com.au Get Work in Child Care Certificate III Children's Services 4 Day Course + Take Home Assessment HBAconsult.com.au Abstract Objective: To assess the potential role of Family Day Care in nutrition promotion for preschool children. Design and setting: A questionnaire to examine nutrition-related issues and practices was mailed to care providers registered in the southern region of Adelaide, South Australia. Care providers also supplied a descriptive, qualitative recall of the food provided by parents or themselves to each child less than five years of age in their care on the day closest to completion of the questionnaire. Subjects: 255 care providers. The response rate was 63% and covered 643 preschool children, mean 4.6 (SD 2.8) children per carer. Results: There was clear agreement that nutrition promotion was a relevant issue for Family Day Care providers. Nutrition and food hygiene knowledge was good but only 54% of respondents felt confident to address food quality issues with parents. Sixty-five percent of respondents reported non-neutral approaches to food refusal and dawdling (reward, punishment, cajoling) that overrode the child's control of the amount eaten. The food recalls indicated that most children (> 75%) were offered fruit at least once. Depending on the hours in care, (0 to 4, 5 to 8, greater than 8 hours), 20%, 32% and 55%, respectively, of children were offered milk and 65%, 82% and 87%, respectively, of children were offered high fat and sugar foods. Conclusions: Questionnaire responses suggest that many care providers are committed to and proactive in a range of nutrition promotion activities. There is scope for strengthening skills in the management of common problems, such as food refusal and dawdling, consistent with the current evidence for approaches to early feeding management that promote the development of healthy food preferences and eating patterns. Legitimising and empowering care providers in their nutrition promotion role requires clear policies, guide lines, adequate pre- and in-service training, suitable parent materials, and monitoring.

Maternal feeding practices and feeding behaviors of Australian children aged 12 to 36 months

Objectives To explore parents' perceptions of the eating behaviors and related feeding practices of their young children. Methods Mothers (N=740) of children aged 12 to 36 months and born in South Australia were randomly selected by birth date in four 6-month age bands from a centralized statewide database and invited to complete a postal questionnaire. Results Valid completed questionnaires were returned for 374 children (51% response rate; 54% female). Although mothers generally reported being confident and happy in feeding their children, 23% often worried that they gave their child the right amount of food. Based on a checklist of 36 specified items, 15% of children consumed no vegetables in the previous 24 hours, 11% no fruit and for a further 8% juice was the only fruit. Of 12 specified high fat/sugar foods and drinks, 11% of children consumed none, 20% one, 26% two, and 43% three or more. Six of eight child-feeding practices that promote healthy eating behaviors were undertaken by 75% parents 'often' or 'all of the time'. However, 8 of 11 practices that do not promote healthy eating were undertaken by a third of mothers at least ‘sometimes’. Conclusions In this representative sample, dietary quality issues emerge early and inappropriate feeding practices are prevalent thus identifying the need for very early interventions that promote healthy food preferences and positive feeding practices. Such programs should focus not just on the 'what', but also the 'how' of early feeding, including the feeding relationship and processes appropriate to developmental stage. Key words: Maternal feeding practices, infants, obesity

The effect of exercise intensity on fat oxidation and non-exercise activity thermogenesis in overweight/obese men

It is frequently reported that the actual weight loss achieved through exercise interventions is less than theoretically expected. Amongst other compensatory adjustments that accompany exercise training (e.g., increases in resting metabolic rate and energy intake), a possible cause of the less than expected weight loss is a failure to produce a marked increase in total daily energy expenditure due to a compensatory reduction in non-exercise activity thermogenesis (NEAT). Therefore, there is a need to understand how behaviour is modified in response to exercise interventions. The proposed benefits of exercise training are numerous, including changes to fat oxidation. Given that a diminished capacity to oxidise fat could be a factor in the aetiology of obesity, an exercise training intensity that optimises fat oxidation in overweight/obese individuals would improve impaired fat oxidation, and potentially reduce health risks that are associated with obesity. To improve our understanding of the effectiveness of exercise for weight management, it is important to ensure exercise intensity is appropriately prescribed, and to identify and monitor potential compensatory behavioural changes consequent to exercise training. In line with the gaps in the literature, three studies were performed. The aim of Study 1 was to determine the effect of acute bouts of moderate- and high-intensity walking exercise on NEAT in overweight and obese men. Sixteen participants performed a single bout of either moderate-intensity walking exercise (MIE) or high-intensity walking exercise (HIE) on two separate occasions. The MIE consisted of walking for 60-min on a motorised treadmill at 6 km.h-1. The 60-min HIE session consisted of walking in 5-min intervals at 6 km.h-1 and 10% grade followed by 5-min at 0% grade. NEAT was assessed by accelerometer three days before, on the day of, and three days after the exercise sessions. There was no significant difference in NEAT vector magnitude (counts.min-1) between the pre-exercise period (days 1-3) and the exercise day (day 4) for either protocol. In addition, there was no change in NEAT during the three days following the MIE session, however NEAT increased by 16% on day 7 (post-exercise) compared with the exercise day (P = 0.32). During the post-exercise period following the HIE session, NEAT was increased by 25% on day 7 compared with the exercise day (P = 0.08), and by 30-33% compared with the pre-exercise period (day 1, day 2 and day 3); P = 0.03, 0.03, 0.02, respectively. To conclude, a single bout of either MIE or HIE did not alter NEAT on the exercise day or on the first two days following the exercise session. However, extending the monitoring of NEAT allowed the detection of a 48 hour delay in increased NEAT after performing HIE. A longer-term intervention is needed to determine the effect of accumulated exercise sessions over a week on NEAT. In Study 2, there were two primary aims. The first aim was to test the reliability of a discontinuous incremental exercise protocol (DISCON-FATmax) to identify the workload at which fat oxidation is maximised (FATmax). Ten overweight and obese sedentary male men (mean BMI of 29.5 ¡Ó 4.5 kg/m2 and mean age of 28.0 ¡Ó 5.3 y) participated in this study and performed two identical DISCON-FATmax tests one week apart. Each test consisted of alternate 4-min exercise and 2-min rest intervals on a cycle ergometer. The starting work load of 28 W was increased every 4-min using 14 W increments followed by 2-min rest intervals. When the respiratory exchange ratio was consistently >1.0, the workload was increased by 14 W every 2-min until volitional exhaustion. Fat oxidation was measured by indirect calorimetry. The mean FATmax, ƒtV O2peak, %ƒtV O2peak and %Wmax at which FATmax occurred during the two tests were 0.23 ¡Ó 0.09 and 0.18 ¡Ó 0.08 (g.min-1); 29.7 ¡Ó 7.8 and 28.3 ¡Ó 7.5 (ml.kg-1.min-1); 42.3 ¡Ó 7.2 and 42.6 ¡Ó 10.2 (%ƒtV O2max) and 36.4 ¡Ó 8.5 and 35.4 ¡Ó 10.9 (%), respectively. A paired-samples T-test revealed a significant difference in FATmax (g.min-1) between the tests (t = 2.65, P = 0.03). The mean difference in FATmax was 0.05 (g.min-1) with the 95% confidence interval ranging from 0.01 to 0.18. Paired-samples T-test, however, revealed no significant difference in the workloads (i.e. W) between the tests, t (9) = 0.70, P = 0.4. The intra-class correlation coefficient for FATmax (g.min-1) between the tests was 0.84 (95% confidence interval: 0.36-0.96, P < 0.01). However, Bland-Altman analysis revealed a large disagreement in FATmax (g.min-1) related to W between the two tests; 11 ¡Ó 14 (W) (4.1 ¡Ó 5.3 ƒtV O2peak (%)).These data demonstrate two important phenomena associated with exercise-induced substrate oxidation; firstly, that maximal fat oxidation derived from a discontinuous FATmax protocol differed statistically between repeated tests, and secondly, there was large variability in the workload corresponding with FATmax. The second aim of Study 2 was to test the validity of a DISCON-FATmax protocol by comparing maximal fat oxidation (g.min-1) determined by DISCON-FATmax with fat oxidation (g.min-1) during a continuous exercise protocol using a constant load (CONEX). Ten overweight and obese sedentary males (BMI = 29.5 ¡Ó 4.5 kg/m2; age = 28.0 ¡Ó 4.5 y) with a ƒtV O2max of 29.1 ¡Ó 7.5 ml.kg-1.min-1 performed a DISCON-FATmax test consisting of alternate 4-min exercise and 2-min rest intervals on a cycle ergometer. The 1-h CONEX protocol used the workload from the DISCON-FATmax to determine FATmax. The mean FATmax, ƒtV O2max, %ƒtV O2max and workload at which FATmax occurred during the DISCON-FATmax were 0.23 ¡Ó 0.09 (g.min-1); 29.1 ¡Ó 7.5 (ml.kg-1.min-1); 43.8 ¡Ó 7.3 (%ƒtV O2max) and 58.8 ¡Ó 19.6 (W), respectively. The mean fat oxidation during the 1-h CONEX protocol was 0.19 ¡Ó 0.07 (g.min-1). A paired-samples T-test revealed no significant difference in fat oxidation (g.min-1) between DISCON-FATmax and CONEX, t (9) = 1.85, P = 0.097 (two-tailed). There was also no significant correlation in fat oxidation between the DISCON-FATmax and CONEX (R=0.51, P = 0.14). Bland- Altman analysis revealed a large disagreement in fat oxidation between the DISCONFATmax and CONEX; the upper limit of agreement was 0.13 (g.min-1) and the lower limit of agreement was ¡V0.03 (g.min-1). These data suggest that the CONEX and DISCONFATmax protocols did not elicit different rates of fat oxidation (g.min-1). However, the individual variability in fat oxidation was large, particularly in the DISCON-FATmax test. Further research is needed to ascertain the validity of graded exercise tests for predicting fat oxidation during constant load exercise sessions. The aim of Study 3 was to compare the impact of two different intensities of four weeks of exercise training on fat oxidation, NEAT, and appetite in overweight and obese men. Using a cross-over design 11 participants (BMI = 29 ¡Ó 4 kg/m2; age = 27 ¡Ó 4 y) participated in a training study and were randomly assigned initially to: [1] a lowintensity (45%ƒtV O2max) exercise (LIT) or [2] a high-intensity interval (alternate 30 s at 90%ƒtV O2max followed by 30 s rest) exercise (HIIT) 40-min duration, three times a week. Participants completed four weeks of supervised training and between cross-over had a two week washout period. At baseline and the end of each exercise intervention,ƒtV O2max, fat oxidation, and NEAT were measured. Fat oxidation was determined during a standard 30-min continuous exercise bout at 45%ƒtV O2max. During the steady state exercise expired gases were measured intermittently for 5-min periods and HR was monitored continuously. In each training period, NEAT was measured for seven consecutive days using an accelerometer (RT3) the week before, at week 3 and the week after training. Subjective appetite sensations and food preferences were measured immediately before and after the first exercise session every week for four weeks during both LIT and HIIT. The mean fat oxidation rate during the standard continuous exercise bout at baseline for both LIT and HIIT was 0.14 ¡Ó 0.08 (g.min-1). After four weeks of exercise training, the mean fat oxidation was 0.178 ¡Ó 0.04 and 0.183 ¡Ó 0.04 g.min-1 for LIT and HIIT, respectively. The mean NEAT (counts.min-1) was 45 ¡Ó 18 at baseline, 55 ¡Ó 22 and 44 ¡Ó 16 during training, and 51 ¡Ó 14 and 50 ¡Ó 21 after training for LIT and HIIT, respectively. There was no significant difference in fat oxidation between LIT and HIIT. Moreover, although not statistically significant, there was some evidence to suggest that LIT and HIIT tend to increase fat oxidation during exercise at 45% ƒtV O2max (P = 0.14 and 0.08, respectively). The order of training treatment did not significantly influence changes in fat oxidation, NEAT, and appetite. NEAT (counts.min-1) was not significantly different in the week following training for either LIT or HIIT. Although not statistically significant (P = 0.08), NEAT was 20% lower during week 3 of exercise training in HIIT compared with LIT. Examination of appetite sensations revealed differences in the intensity of hunger, with higher ratings after LIT compared with HIIT. No differences were found in preferences for high-fat sweet foods between LIT and HIIT. In conclusion, the results of this thesis suggest that while fat oxidation during steady state exercise was not affected by the level of exercise intensity, there is strong evidence to suggest that intense exercise could have a debilitative effect on NEAT.

Gender and the capacity of women with NIDDM to implement medical advice

This qualitative study of women with non-insulin dependent diabetes mellitus (NIDDM) examined constructions of their diabetes management and socio-familial relationships as potential sources of support. Semi-structured interview data was collected from 16 women. The transcripts were analysed with the aim of examining the ways in which Sender relations structured women's accounts of health-related behaviours. Women talked about themselves as wives, mothers, being pregnant and parenting, and friends of other women in ways that demonstrated how caring for others impeded their capacity to care for themselves. Meeting the food preferences of husbands and dietary requirements of diabetic husbands were dominant themes in women's accounts of marriage, and in various ways women justified their husbands' lack of support. Furthermore, the care of others during pregnancy and parenting was also an obstacle to women caring for themselves. An awareness of the gender politics inherent within social and family contexts is crucial to improving the effectiveness of medical advice for diabetes management.

Child eating behaviour outcomes of an early feeding intervention to reduce risk indicators for child obesity : the NOURISH RCT

Objective Describe parent-reported child eating behaviour and maternal parenting impact outcomes of an infant feeding intervention to reduce child obesity risk. Design and Methods An assessor masked Randomised Controlled Trial (RCT) with concealed allocation of individual mother-infant dyads. The NOURISH RCT enrolled 698 first-time mothers (mean age 30.1 years, SD=5.3) with healthy term infants (51% female) aged 4.3 months (SD=1.0) at baseline. Outcomes were assessed six months post-intervention when the children were 2-years old. Mothers reported on child eating behaviours using the Child Eating Behaviour Questionnaire (CEBQ), food preferences and dietary intake using a 24-hour telephone recall. Parenting was assessed using five scales validated for use in Australia. Results Intervention effects were evident on the CEBQ overall (MANOVA P=.002) and 4/8 subscales: child satiety responsiveness (P=.03), fussiness (P=.01), emotional overeating (P<.01), and food responsiveness (P=.06). Intervention children ‘liked’ more fruits (P<.01) and fewer non-core foods and beverages (Ps=.06, .03). The intervention mothers reported greater ‘autonomy encouragement’ (P=.002) Conclusions Anticipatory guidance on protective feeding practices appears to have modest positive impacts on child eating behaviours that are postulated to reduce future obesity risk.

Observing the mother-infant feeding interaction

Early parenting is critical to effective attachment and a range of positive developmental outcomes for children. Feeding is a key task of early parenting and increasing evidence indicates that early feeding practices are important for the development of self-regulation of intake and food preferences which in turn are predictors of later obesity risk. However, relatively little is known about the mother-infant interaction at the transition to solids among typically developing children. This study aimed to describe parenting strategies used by mothers at the transition from milk feeding to solid food. Twenty mother-infant dyads were video-taped during a feeding interaction and data was analysed to describe maternal use of parenting strategies. It was predicted that positive feeding strategies would be correlated with lower levels of Infant Food Refusal (IFR), higher maternal sensitivity, and better overall parenting scores. The opposite was predicted for negative feeding strategies. It was found that positive strategy use and general parenting scores were significantly correlated in the predicted direction, however maternal instruction, aversive contact and ineffective strategy use were significantly correlated with and predictive of IFR. Additionally, it was hypothesised that maternal strategy use would deteriorate towards the end of the interaction, and this hypothesis was partially supported: significantly more negative strategy use was observed in the last third of the interaction, whilst positive strategy use remained consistent through the feeding interaction. The findings have important implications for early feeding parent education and intervention programs.

Feeding a baby (FAB) study. Reducing childhood obesity : influencing parental infant feeding practices

Background National and international rates of obesity are escalating, and programs to modify established eating habits are having limited success. Almost one in four 2-4 year old Australian children are overweight or obese. Interventions to prevent obesity in early childhood are on the rise. However, recruitment and retention issues and outcomes to date suggests a gap in meeting participant needs. Parents need both the knowledge and skills to establish behaviours that enable children to develop healthy food preferences and eating habits early. AIM To develop intervention recommendations to reduce childhood obesity by improving the infant feeding practices of parents, focusing on the transition from a milk diet to family foods.

Parent feeding interactions and practices during childhood cancer treatment: A qualitative investigation

In the general population it is evident that parent feeding practices can directly shape a child’s life long dietary intake. Young children undergoing childhood cancer treatment may experience feeding difficulties and limited food intake, due to the inherent side effects of their anti-cancer treatment. What is not clear is how these treatment side effects are influencing the parent–child feeding relationship during anti-cancer treatment. This retrospective qualitative study collected telephone based interview data from 38 parents of childhood cancer patients who had recently completed cancer treatment (child’s mean age: 6.98 years). Parents described a range of treatment side effects that impacted on their child’s ability to eat, often resulting in weight loss. Sixty-one percent of parents (n = 23) reported high levels of stress in regard to their child’s eating and weight loss during treatment. Parents reported stress, feelings of helplessness, and conflict and/or tension between parent and the child during feeding/eating interactions. Parents described using both positive and negative feeding practices, such as: pressuring their child to eat, threatening the insertion of a nasogastric feeding tube, encouraging the child to eat and providing home cooked meals in hospital. Results indicated that parent stress may lead to the use of coping strategies such as positive or negative feeding practices to entice their child to eat during cancer treatment. Future research is recommended to determine the implication of parent feeding practice on the long term diet quality and food preferences of childhood cancer survivors.

Dietary intake of children aged 12-16 months and associations with maternal feeding beliefs and practices

This thesis provides the first detailed data describing the dietary intake of first-born Australian children aged 12-16 months. Overall, quality of intake could improve, with toddlers being exposed to energy-dense, nutrient-poor foods which may adversely affect the development of long-term healthy food preferences and growth trajectory. The leaner, but healthy weight toddler who exhibited more frequent food refusal was described a fussy eater or prompted higher maternal concern. However these behaviours are consistent with typical child development during the second year of life. Mothers can be supported to understand food refusal as manifestation of children's ability to self-regulate energy intake.

Interval training intensity affects energy intake compensation in obese men

Abstract PURPOSE: Compensatory responses may attenuate the effectiveness of exercise training in weight management. The aim of this study was to compare the effect of moderate- and high-intensity interval training on eating behavior compensation. METHODS: Using a crossover design, 10 overweight and obese men participated in 4-week moderate (MIIT) and high (HIIT) intensity interval training. MIIT consisted of 5-min cycling stages at ± 20% of mechanical work at 45%VO(2)peak, and HIIT consisted of alternate 30-s work at 90%VO(2)peak and 30-s rests, for 30 to 45 min. Assessments included a constant-load exercise test at 45%VO(2)peak for 45 min followed by 60-min recovery. Appetite sensations were measured during the exercise test using a Visual Analog Scale. Food preferences (liking and wanting) were assessed using a computer-based paradigm, and this paradigm uses 20 photographic food stimuli varying along two dimensions, fat (high or low) and taste (sweet or nonsweet). An ad libitum test meal was provided after the constant-load exercise test. RESULTS: Exercise-induced hunger and desire to eat decreased after HIIT, and the difference between MIIT and HIIT in desire to eat approached significance (p = .07). Exercise-induced liking for high-fat nonsweet food tended to increase after MIIT and decreased after HIIT (p = .09). Fat intake decreased by 16% after HIIT, and increased by 38% after MIIT, with the difference between MIIT and HIIT approaching significance (p = .07). CONCLUSIONS: This study provides evidence that energy intake compensation differs between MIIT and HIIT.

Child dietary and eating behaviour outcomes up to 3.5 years after an early feeding intervention: the NOURISH RCT

- Objective To evaluate dietary intake impact outcomes up to 3.5 years after the NOURISH early feeding intervention (concealed allocation, assessor masked RCT). - Methods 698 first-time mothers with healthy term infants were allocated to receive anticipatory guidance on protective feeding practices or usual care. Outcomes were assessed at 2, 3.7 and 5 years (3.5 years post-intervention). Dietary intake was assessed by 24-hour recall and Child Dietary Questionnaire. Mothers completed a food preference questionnaire and Children’s Eating Behaviour Questionnaire. Linear mixed models assessed group, time and time x group effects. - Results There were no group or time x group effects for fruit, vegetables, discretionary food and non-milk sweetened beverages intake. Intervention children showed a higher preference for fruits (74.6% vs 69.0% liked, P<.001), higher Child Dietary Questionnaire score for fruit and vegetables (15.3 vs 14.5, target>18, P=0.03), lower food responsiveness (2.3 vs 2.4, of maximum 5, P=.04) and higher satiety responsiveness (3.1 vs 3.0, of maximum 5, P=.04). - Conclusions Compared to usual care, an early feeding intervention providing anticipatory guidance regarding positive feeding practices led to small improvements in child dietary score, food preferences and eating behaviours up to 5 years of age, but not in dietary intake measured by 24-hour recall.

Some preliminary observations on the biology of Strongylocentrotus lividus (Lamarck)

The present study of Strongylocentrotus lividus is an attempt to add to the knowledge in this field with particular reference to a tropical species of whose biology little is known. The aim of the study was to examine the growth of the animals in relation to the development of their gonads, to elucidate the food preferences of the sea urchins and to study their associations with other animals.

Natural diet of penaeid prawns in the coastal waters of Mumbai

Foregut contents of eight commercially important species of penaied prawns namely Penaeus merguiensis, Metapenaeus affinis, M. monoceros, M. brevicornis, Parapenaeopsis stylifera, P. hardwickii, P. sculptilis and Solenocera crassicornis were investigated from inshore, nearshore and offshore fishing grounds of Mumbai. Feeding intensity and index of preponderance (IP) of the dietary items were compared statistically for the species, sexes, fishing areas and maturity condition of females. All the species except M. monoceros and P. sculptilis showed that females were better fed than males. The feeding intensity in the three depth-zones was different for M. affinis, M. brevicornis, M. monoceros, P. hardwickii and S. crassicornis, and uniform for P. merguiensis, P. stylifera and P. sculptilis. Acetes spp., prawn remains, polychaetes, benthic crustaceans, foraminifers and fish remains were the important food items of the prawns. Dietary comparison between the two sexes of the species did not show any difference, but mature females of M. monoceros and P. sculptilis had different diets. Comparison of food items for all the species together showed significant difference between the three areas. Crustacean diet was the favorite in the inshore and nearshore, and polychaetes in the offshore waters. All the species except P. hardwickii showed difference in their dietary composition in the three depth-zones. It is concluded that these coexisting species are primarily carnivorous and exhibit diverse food preferences in different depth-zones by browsing on interstitial organisms, chasing epipelagic prey, raptorial predation, scavenging on dead organisms or adopting different temporal abundance to avoid inter-specific competition for food.

Predictive neural coding of reward preference involves dissociable responses in human ventral midbrain and ventral striatum.

Food preferences are acquired through experience and can exert strong influence on choice behavior. In order to choose which food to consume, it is necessary to maintain a predictive representation of the subjective value of the associated food stimulus. Here, we explore the neural mechanisms by which such predictive representations are learned through classical conditioning. Human subjects were scanned using fMRI while learning associations between arbitrary visual stimuli and subsequent delivery of one of five different food flavors. Using a temporal difference algorithm to model learning, we found predictive responses in the ventral midbrain and a part of ventral striatum (ventral putamen) that were related directly to subjects' actual behavioral preferences. These brain structures demonstrated divergent response profiles, with the ventral midbrain showing a linear response profile with preference, and the ventral striatum a bivalent response. These results provide insight into the neural mechanisms underlying human preference behavior.