Determining consumer expectations, attitudes and buying behaviour towards “low input” and organic foods

This paper reviews the first results and achievements of the QLIF SP1 “Determining consumer expectations and attitudes towards organic/low input food quality and safety”. The paper aims to illustrate the array of methodologies used and to discuss the ongoing research in light of the first results

Actual and potential development of consumer demand on the organic food market in Europe

AbstractDevelopment of demand for organic foods on three European markets (Denmark, Italy and UK) was investigated by means of quantitative analysis of household panel data and qualitative analysis of consumer life stories and shopping patterns. Potential development was investigated by means of scenario analysis undertaken by experts. Considerable differences between households underlay patterns of increasing aggregate demand at national levels, and fluctuations over time were identified at the household level. Interest in purchasing organic products on a regular basis and actual changes in shopping practices did not proceed apace. Limited availability has constituted a major barrier to increasing demand among ‘regular’ users. Demand on the part of ‘occasional’ users reflected a wider range of barriers, including lack of interest in and knowledge about production and processing and lack of trust in stakeholders and certification procedures. A likely scenario for future demand is that of continued stable expansion, dependent upon whether increasing input costs will favour organic production, whether the relative gap between organic and conventional food prices becomes smaller, whether organic products will be distributed more widely on national markets, and whether support for research and conversion of organic production systems on the part of public authorities is enhanced

Pavlovian Reward Prediction and Receipt in Schizophrenia: Relationship to Anhedonia

Reward processing abnormalities have been implicated in the pathophysiology of negative symptoms such as anhedonia and avolition in schizophrenia. However, studies examining neural responses to reward anticipation and receipt have largely relied on instrumental tasks, which may confound reward processing abnormalities with deficits in response selection and execution. 25 chronic, medicated outpatients with schizophrenia and 20 healthy controls underwent functional magnetic resonance imaging using a Pavlovian reward prediction paradigm with no response requirements. Subjects passively viewed cues that predicted subsequent receipt of monetary reward or non-reward, and blood-oxygen-level-dependent signal was measured at the time of cue presentation and receipt. At the group level, neural responses to both reward anticipation and receipt were largely similar between groups. At the time of cue presentation, striatal anticipatory responses did not differ between patients and controls. Right anterior insula demonstrated greater activation for nonreward than reward cues in controls, and for reward than nonreward cues in patients. At the time of receipt, robust responses to receipt of reward vs. nonreward were seen in striatum, midbrain, and frontal cortex in both groups. Furthermore, both groups demonstrated responses to unexpected versus expected outcomes in cortical areas including bilateral dorsolateral prefrontal cortex. Individual difference analyses in patients revealed an association between physical anhedonia and activity in ventral striatum and ventromedial prefrontal cortex during anticipation of reward, in which greater anhedonia severity was associated with reduced activation to money versus no-money cues. In ventromedial prefrontal cortex, this relationship held among both controls and patients, suggesting a relationship between anticipatory activity and anhedonia irrespective of diagnosis. These findings suggest that in the absence of response requirements, brain responses to reward receipt are largely intact in medicated individuals with chronic schizophrenia, while reward anticipation responses in left ventral striatum are reduced in those patients with greater anhedonia severity

Spatiotemporal neural characterization of prediction error valence and surprise during reward learning in humans

Reward learning depends on accurate reward associations with potential choices. These associations can be attained with reinforcement learning mechanisms using a reward prediction error (RPE) signal (the difference between actual and expected rewards) for updating future reward expectations. Despite an extensive body of literature on the influence of RPE on learning, little has been done to investigate the potentially separate contributions of RPE valence (positive or negative) and surprise (absolute degree of deviation from expectations). Here, we coupled single-trial electroencephalography with simultaneously acquired fMRI, during a probabilistic reversal-learning task, to offer evidence of temporally overlapping but largely distinct spatial representations of RPE valence and surprise. Electrophysiological variability in RPE valence correlated with activity in regions of the human reward network promoting approach or avoidance learning. Electrophysiological variability in RPE surprise correlated primarily with activity in regions of the human attentional network controlling the speed of learning. Crucially, despite the largely separate spatial extend of these representations our EEG-informed fMRI approach uniquely revealed a linear superposition of the two RPE components in a smaller network encompassing visuo mnemonic and reward areas. Activity in this network was further predictive of stimulus value updating indicating a comparable contribution of both signals to reward learning

Disambiguating ventral striatum fMRI-related bold signal during reward prediction in schizophrenia

Reward detection, surprise detection and prediction-error signaling have all been proposed as roles for the ventral striatum (vStr). Previous neuroimaging studies of striatal function in schizophrenia have found attenuated neural responses to reward-related prediction errors; however, as prediction errors represent a discrepancy in mesolimbic neural activity between expected and actual events, it is critical to examine responses to both expected and unexpected rewards (URs) in conjunction with expected and UR omissions in order to clarify the nature of ventral striatal dysfunction in schizophrenia. In the present study, healthy adults and people with schizophrenia were tested with a reward-related prediction-error task during functional magnetic resonance imaging to determine whether schizophrenia is associated with altered neural responses in the vStr to rewards, surprise prediction errors or all three factors. In healthy adults, we found neural responses in the vStr were correlated more specifically with prediction errors than to surprising events or reward stimuli alone. People with schizophrenia did not display the normal differential activation between expected and URs, which was partially due to exaggerated ventral striatal responses to expected rewards (right vStr) but also included blunted responses to unexpected outcomes (left vStr). This finding shows that neural responses, which typically are elicited by surprise, can also occur to well-predicted events in schizophrenia and identifies aberrant activity in the vStr as a key node of dysfunction in the neural circuitry used to differentiate expected and unexpected feedback in schizophrenia

Dietary advice for muscularity, leanness and weight control in Men's Health magazine: a content analysis

Background: The dietary content of advice in men’s lifestyle magazines has not been closely scrutinised. Methods: We carried out an analysis of such content in all 2009 issues (n = 11) of Men’s Health (MH) focusing on muscularity, leanness and weight control. Results: Promotion of a mesomorphic body image underpinned advice to affect muscle building and control weight. Diet advice was underpinned by a strong pseudo-scientific discourse, with citation of expert sources widely used to legitimise the information. Frequently multiple dietary components were advocated within one article e.g. fat, omega-3 fatty acids, thiamine, zinc and high-glycaemic index foods. Furthermore advice would cover numerous nutritional effects, e.g. strengthening bones, reducing stress and boosting testosterone, with little contextualisation. The emphasis on attainment of a mesomorphic body image permitted promotion of slimming diets. Advice to increase calorie and protein intake to augment muscle mass was frequent (183 and 262 references, respectively). Such an anabolic diet was advised in various ways, including consumption of traditional protein foods (217 references) and sports foods (107 references), thereby replicating muscle magazines’ support for nutritional supplements. Although advice to increase consumption of red meat was common (52 references), fish and non-flesh sources of protein (eggs, nuts & pulses, and soy products) together exceeded red meat in number of recommendations (206 references). Advice widely asserted micronutrients and phytochemicals from plant food (161 references) as being important in muscle building. This emphasis diverges from stereotypical gender-based food consumption patterns. Dietary advice for control of body weight largely replicated that of muscularity, with strong endorsement to consume fruits and vegetables (59 references), diets rich in nuts and pulses and fish (66 references), as well as specific micronutrients and phytochemicals (62 references). Notably there was emphasis on fat-burning, good fats and consumption of single foods, with relatively little mention of dietary restriction. Conclusions: Despite the widespread use of scientific information to endorse dietary advice, the content, format and scientific basis of dietary content of MH leaves much to be desired. The dietary advice as provided may not be conducive to public health

Effort-related functions of nucleus accumbens dopamine and associated forebrain circuits

Background Over the last several years, it has become apparent that there are critical problems with the hypothesis that brain dopamine (DA) systems, particularly in the nucleus accumbens, directly mediate the rewarding or primary motivational characteristics of natural stimuli such as food. Hypotheses related to DA function are undergoing a substantial restructuring, such that the classic emphasis on hedonia and primary reward is giving way to diverse lines of research that focus on aspects of instrumental learning, reward prediction, incentive motivation, and behavioral activation. Objective The present review discusses dopaminergic involvement in behavioral activation and, in particular, emphasizes the effort-related functions of nucleus accumbens DA and associated forebrain circuitry. Results The effects of accumbens DA depletions on food-seeking behavior are critically dependent upon the work requirements of the task. Lever pressing schedules that have minimal work requirements are largely unaffected by accumbens DA depletions, whereas reinforcement schedules that have high work (e.g., ratio) requirements are substantially impaired by accumbens DA depletions. Moreover, interference with accumbens DA transmission exerts a powerful influence over effort-related decision making. Rats with accumbens DA depletions reallocate their instrumental behavior away from food-reinforced tasks that have high response requirements, and instead, these rats select a less-effortful type of food-seeking behavior. Conclusions Along with prefrontal cortex and the amygdala, nucleus accumbens is a component of the brain circuitry regulating effort-related functions. Studies of the brain systems regulating effort-based processes may have implications for understanding drug abuse, as well as energy-related disorders such as psychomotor slowing, fatigue, or anergia in depression