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Contains fulltext : 230060.pdf (Publisher’s version ) (Closed access), Many American and Dutch adolescents use marijuana regularly. There is concern that such use may impair cognitive function more in adolescents than adults. We examined effects of regular marijuana use on long-term memory and perseveration among American and Dutch adolescents. We administered Buschke's Selective Reminding Test (BSRT) to assess long-term memory and the Wisconsin Card Sorting Test (WCST) to assess perseveration in male teenagers. Usable test data were obtained for 12 American marijuana users, 13 American controls, 9 Dutch marijuana users, and 12 Dutch controls. In BSRT, users showed lower overall long-term storage than controls (adjusted means ± SE's for numbers of words per trial of 9.4 ± 0.2, 13.4 ± 0.3, 11.7 ± 0.2, and 12.4 ± 0.2 for American users, Dutch users, American controls, and Dutch controls, respectively). Marijuana was associated with memory effects only in American, not Dutch, users. Bivariate Pearson correlations for American and Dutch users combined showed associations of lower total recall with more uses in the previous year and lifetime (r = -0.61 and r = -0.53, respectively); and more perseverative errors with more uses in the previous year (r = 0.55). Some findings were consistent with the possibility that regular adolescent marijuana use causes deficits in cognition, especially memory. However, a causal interpretation cannot be inferred from our findings and is challenging to reconcile with the observation of memory deficits only in American users. Our study was novel in examining the influence of nationality on marijuana's cognitive effects. More studies of this topic should compare effects across nationalities or cultures.

Socioeconomic disparities in diet quality continue to prevail, and already emerge in childhood. Children from families with a low socioeconomic position (SEP) consume unhealthier diets than children from families with a higher SEP. However, populations with a low SEP are least reached by interventions to improve diet quality and other lifestyle factors, which paradoxically could result in an increase of the disparity in diet quality and eating behaviors between populations with lower and higher SEPs. Moreover, populations with a low SEP are underrepresented in research. Instead of focusing on reducing the socioeconomic inequalities in health and dietary status, it may be more effective to focus on the health “potential” of populations with a low SEP, and especially children, as they are the ones where the benefits of improved dietary patterns and eating behaviors have the biggest impact.The research reported in this thesis set out to investigate how health potential could be realized via improving eating behaviors in the everyday life of families with a low SEP. There are differences between populations with low and higher SEPs with regard to food preference, i.e., what they (dis)like, and what they believe is healthy or not, and (not) tasty. Therefore, this thesis aimed to provide insight in how these differences arise, and what the meaning is of “(un)healthy” and (not) “tasty”, and what it means to “like” or “dislike” a food, in the everyday life of families with a low SEP. A multidisciplinary approach was deployed, combining perspectives from nutrition sciences and psychology, diverse theoretical approaches, and quantitative and qualitative research methods.The range of implicit (i.e., unconscious) and explicit (i.e., conscious) associations between (un)healthiness, (not) tastiness and (dis)liking of foods was mapped in primary school-aged children and parents from families with a low SEP. 37 primary school-aged children and their parents participated in im

31 januari 2021, Contains fulltext : 230060.pdf (Publisher’s version ) (Closed access), Many American and Dutch adolescents use marijuana regularly. There is concern that such use may impair cognitive function more in adolescents than adults. We examined effects of regular marijuana use on long-term memory and perseveration among American and Dutch adolescents. We administered Buschke's Selective Reminding Test (BSRT) to assess long-term memory and the Wisconsin Card Sorting Test (WCST) to assess perseveration in male teenagers. Usable test data were obtained for 12 American marijuana users, 13 American controls, 9 Dutch marijuana users, and 12 Dutch controls. In BSRT, users showed lower overall long-term storage than controls (adjusted means ± SE's for numbers of words per trial of 9.4 ± 0.2, 13.4 ± 0.3, 11.7 ± 0.2, and 12.4 ± 0.2 for American users, Dutch users, American controls, and Dutch controls, respectively). Marijuana was associated with memory effects only in American, not Dutch, users. Bivariate Pearson correlations for American and Dutch users combined showed associations of lower total recall with more uses in the previous year and lifetime (r = -0.61 and r = -0.53, respectively); and more perseverative errors with more uses in the previous year (r = 0.55). Some findings were consistent with the possibility that regular adolescent marijuana use causes deficits in cognition, especially memory. However, a causal interpretation cannot be inferred from our findings and is challenging to reconcile with the observation of memory deficits only in American users. Our study was novel in examining the influence of nationality on marijuana's cognitive effects. More studies of this topic should compare effects across nationalities or cultures.

BACKGROUND: The start of complementary feeding in infancy plays an essential role in promoting healthy eating habits. Evidence shows that it is important what infants are offered during this first introduction of solid foods: e.g. starting exclusively with vegetables is more successful for vegetable acceptance than starting with fruits. How infants are introduced to solid foods also matters: if parents are sensitive and responsive to infant cues during feeding, this may promote self-regulation of energy intake and a healthy weight. However, the effectiveness of the what and the how of complementary feeding has never been experimentally tested in the same study. In the current project the what and how (and their combination) are tested in one study to determine their relative importance for fostering vegetable acceptance and self-regulation of energy intake in infants. METHODS: A four-arm randomized controlled trial (Baby's First Bites (BFB)) was designed for 240 first-time Dutch mothers and their infants, 60 per arm. In this trial, we compare the effectiveness of (a) a vegetable-exposure intervention focusing on the what in complementary feeding; (b) a sensitive feeding intervention focusing on the how in complementary feeding, (c) a combined intervention focusing on the what and how in complementary feeding; (d) an attention-control group. All mothers participate in five sessions spread over the first year of eating solid foods (child age 4-16 months). Primary outcomes are vegetable consumption, vegetable liking and self-regulation of energy intake. Secondary outcomes are child eating behaviors, child anthropometrics and maternal feeding behavior. Outcomes are assessed before, during and directly after the interventions (child age 18 months), and when children are 24 and 36 months old. DISCUSSION: The outcomes are expected to assess the impact of the interventions and provide new insights into the mechanisms underlying the development of vegetable acceptance, self

A novel effort-based task (Grab-to-Eat Task (GET)) utilising handgrip force as a measure of motivation has been developed with the aim of capturing eating desire dynamics throughout meal consumption. Published here: https://doi.org/10.1016/j.foodqual.2019.103741, A novel effort-based task (Grab-to-Eat Task (GET)) utilising handgrip force as a measure of motivation has been developed with the aim of capturing eating desire dynamics throughout meal consumption. Published here: https://doi.org/10.1016/j.foodqual.2019.103741

Healthier foods are often less tasty, less preferred and less rewarding compared to their regular counterparts. Although the principle basis of food preference is the attractiveness of flavour, other factors (e.g., package colour) are also important contributors to product perception and preference. Healthier foods are often packaged differently compared to regular products (i.e., less vibrantly coloured vs. more vibrantly coloured respectively). In her dissertation Irene Tijssen looked at the effects of several package colour aspects on the perception of the healthier products themselves. She found that packaging healthier foods in warmer, more saturated package colours (i.e., more vibrantly coloured) may render them more flavourful, more attractive and more rewarding. This could lead to an increase in preference for healthier foods, without changing the actual product itself. She demonstrates the abilities of package colour properties to make healthier foods more attractive and demonstrates importance of package colour aspects when designing healthier products.

Background: Roux-en-Y gastric bypass (RYGB) surgery is a highly effective weight-loss intervention that often reduces preference and intake of high-energy foods. Research into the neural mechanisms behind this shift has mainly focused on reward processing of food cues. However, the ability to successfully control food intake and thereby weight-loss also depends on inhibitory control capacity. We investigated whether RYGB leads to alterations in neural inhibitory control in response to food cues. Methods: A food-specific go/no-go task with pictures of high-energy (desserts) and low-energy foods (vegetables), was used to assess neural inhibition responses before and after RYGB with functional magnetic resonance imaging. Data from 18 morbidly obese patients (15 females; age 41 ± 11 years; BMI 42 ± 4 kg/m2 before; BMI 36 ± 4 kg/m2 after) were analysed. Pre- and post-RYGB BOLD fMRI responses were compared for response inhibition towards high- and low-energy foods. Participants were tested in a satiated state. Results: Response inhibition to high-energy foods was associated with increased activation of the right lateral prefrontal cortex (PFC), right medial PFC, dorsolateral PFC, right middle cingulate cortex and the right inferior frontal operculum (involved in inhibitory control), after compared to before surgery. Response inhibition to low-energy foods elicited diminished post- compared to pre-surgery responses in the left superior temporal pole, right parahippocampal gyrus and right hypothalamus (involved in metabolic control). Conclusion: Neural changes indicate improved response inhibition towards high-energy food cues, altered influence of metabolic control during response inhibition towards low-energy food cues and a more positive attitude to both high-energy and low-energy food after RYGB. Alterations in neural circuits involved in inhibitory control, satiety signalling and reward processing may contribute to effective weight-loss after RYGB.

Wine and beer consumption are an integral part of European culture: Southern Europe is associated with wine and Northern Europe is associated with beer. When consumed in moderation, these alcoholic beverages can be part of a balanced and healthy diet. In the 1990s, non-alcoholic beer, which has no cultural roots, became available in the market. This reviewidentifies determinants for consumption of wine, beer, and non-alcoholic beer, using data on consumption patterns from Portugal and the Netherlands. Since the 1960s the image of Portugal as a wine country declined, whereas the image of the Netherlands as a beer country remainedstable. In each country beer is now the most consumed alcoholic beverage and is mainly a men‟s beverage, whereas wine is the second most consumed and is consumed by both genders. Culturaldifferences define Portuguese as “outdoors, everyday drinkers”, within a meal context, andDutch as “at home, weekend drinkers.” Wine is perceived as the healthiest beverage, followed bynon-alcoholic beer, and regular beer. Motivation for consumption is related to context: wine forspecial occasions, beer for informal occasions, and non-alcoholic beer for occasions whenalcohol is not convenient. Moderate wine and beer consumption seems to be surrounded bypositive emotions.This review is relevant for public health, for industry market strategies, and identifiesopportunities of future research on drinking behaviour.

Geoscience & Engineering, Civil Engineering and Geosciences

In the current study we show that non-verbal food-evoked emotion scores significantly improve food choice prediction over merely liking scores. Previous research has shown that liking measures correlate with choice. However, liking is no strong predictor for food choice in real life environments. Therefore, the focus within recent studies shifted towards using emotion-profiling methods that successfully can discriminate between products that are equally liked. However, it is unclear how well scores from emotion-profiling methods predict actual food choice and/or consumption. To test this, we proposed to decompose emotion scores into valence and arousal scores using Principal Component Analysis (PCA) and apply Multinomial Logit Models (MLM) to estimate food choice using liking, valence, and arousal as possible predictors. For this analysis, we used an existing data set comprised of liking and food-evoked emotions scores from 123 participants, who rated 7 unlabeled breakfast drinks. Liking scores were measured using a 100-mm visual analogue scale, while food-evoked emotions were measured using 2 existing emotion-profiling methods: a verbal and a non-verbal method (EsSense Profile and PrEmo, respectively). After 7 days, participants were asked to choose 1 breakfast drink from the experiment to consume during breakfast in a simulated restaurant environment. Cross validation showed that we were able to correctly predict individualized food choice (1 out of 7 products) for over 50% of the participants. This number increased to nearly 80% when looking at the top 2 candidates. Model comparisons showed that evoked emotions better predict food choice than perceived liking alone. However, the strongest predictive strength was achieved by the combination of evoked emotions and liking. Furthermore we showed that non-verbal food-evoked emotion scores more accurately predict food choice than verbal food-evoked emotions scores.

Contains fulltext : 122522.pdf (publisher's version ) (Closed access), Adolescents' risk-taking behavior has been linked to a maturational imbalance between reward ("go") and inhibitory-control ("stop")-related brain circuitry. This may drive adolescent drug-taking, such as cannabis use. In this study, we assessed the non-acute effects of adolescent cannabis use on reward-related brain function. We performed a two-site (United States and Netherlands; pooled data) functional magnetic resonance imaging (fMRI) study with a cross-sectional design. Twenty-one abstinent but frequent cannabis-using boys were compared with 24 non-using peers on reward-related brain function, using a monetary incentive delay task with fMRI. Focus was on anticipatory and response stages of reward and brain areas critically involved in reward processing like the striatum. Performance in users was normal. Region-of-interest analysis indicated striatal hyperactivity during anticipatory stages of reward in users. Intriguingly, this effect was most pronounced during non-rewarding events. Striatal hyperactivity in adolescent cannabis users may signify an overly sensitive motivational brain circuitry. Frequent cannabis use during adolescence may induce diminished ability to disengage the motivational circuit when no reward can be obtained. This could strengthen the search for reinforcements like drugs of abuse, even when facing the negative (non-rewarding) consequences.

Evidence is increasing for involvement of the endocannabinoid system in cognitive functions including attention and executive function, as well as in psychiatric disorders characterized by cognitive deficits, such as schizophrenia. Executive function appears to be associated with both modulation of active networks and inhibition of activity in the default mode network. In the present study, we examined the role of the endocannabinoid system in executive function, focusing on both the associated brain network and the default mode network. A pharmacological functional magnetic resonance imaging (fMRI) study was conducted with a placebo-controlled, cross-over design, investigating effects of the endocannabinoid agonist ¿9-tetrahydrocannabinol (THC) on executive function in 20 healthy volunteers, using a continuous performance task with identical pairs. Task performance was impaired after THC administration, reflected in both an increase in false alarms and a reduction in detected targets. This was associated with reduced deactivation in a set of brain regions linked to the default mode network, including posterior cingulate cortex and angular gyrus. Less deactivation was significantly correlated with lower performance after THC. Regions that were activated by the continuous performance task, notably bilateral prefrontal and parietal cortex, did not show effects of THC. These findings suggest an important role for the endocannabinoid system in both default mode modulation and executive function. This may be relevant for psychiatric disorders associated with executive function deficits, such as schizophrenia and ADHD

For efficient production of hydrocarbons from subsurface reservoirs it is important to understand the spatial properties of the reservoir. As there is almost always too little information on the reservoir to build a representative model directly, other techniques have been developed for generating reservoir models. Different assumptions about the distribution of, and relationships between these properties are required for each different technique. However, it is poorly understood how these assumptions, and errors thereof, affect the predictive capability of the resulting reservoir models. In this study these relationships are analyzed from several different perspectives., Geoscience and Engineering, Civil Engineering and Geosciences

Geoscience & Engineering, Civil Engineering and Geosciences

Rationale Disturbed reward processing in humans has been associated with a number of disorders, such as depression, addiction, and attention-deficit hyperactivity disorder. The endocannabinoid (eCB) system has been implicated in reward processing in animals, but in humans, the relation between eCB functioning and reward is less clear. Objectives The current study uses functional magnetic resonance imaging (fMRI) to investigate the role of the eCB system in reward processing in humans by examining the effect of the eCB agonist ¿9-tetrahydrocannabinol (THC) on reward-related brain activity. Methods Eleven healthy males participated in a randomized placebo-controlled pharmacological fMRI study with administration of THC to challenge the eCB system. We compared anticipatory and feedback-related brain activity after placebo and THC, using a monetary incentive delay task. In this task, subjects are notified before each trial whether a correct response is rewarded (“reward trial”) or not (“neutral trial”). Results Subjects showed faster reaction times during reward trials compared to neutral trials, and this effect was not altered by THC. THC induced a widespread attenuation of the brain response to feedback in reward trials but not in neutral trials. Anticipatory brain activity was not affected. Conclusions These results suggest a role for the eCB system in the appreciation of rewards. The involvement of the eCB system in feedback processing may be relevant for disorders in which appreciation of natural rewards may be affected such as addiction

Contains fulltext : 119557.pdf (publisher's version ) (Closed access), Early-onset cannabis use has been associated with later use/abuse, mental health problems (psychosis, depression), and abnormal development of cognition and brain function. During adolescence, ongoing neurodevelopmental maturation and experience shape the neural circuitry underlying complex cognitive functions such as memory and executive control. Prefrontal and temporal regions are critically involved in these functions. Maturational processes leave these brain areas prone to the potentially harmful effects of cannabis use. Method: We performed a two-site (United States and the Netherlands; pooled data) functional magnetic resonance imaging (MRI) study with a cross-sectional design, investigating the effects of adolescent cannabis use on working memory (WM) and associative memory (AM) brain function in 21 abstinent but frequent cannabis using boys (13-19) years of age and compared them with 24 nonusing peers. Brain activity during WM was assessed before and after rule-based learning (automatization). AM was assessed using a pictorial hippocampal-dependent memory task. Results: Cannabis users performed normally on both memory tasks. During WM assessment, cannabis users showed excessive activity in prefrontal regions when a task was novel, whereas automatization of the task reduced activity to the same level in users and controls. No effect of cannabis use on AM-related brain function was found. Conclusions: In adolescent cannabis users, the WM system was overactive during a novel task, suggesting functional compensation. Inefficient WM recruitment was not related to a failure in automatization but became evident when processing continuously changing information. The results seem to confirm the vulnerability of still developing frontal lobe functioning for early-onset cannabis use.