The social insectivore: Peer and expert influence affect consumer evaluations of insects as food.

As conventional animal production is a significant contributor to anthropogenic climate change, eating of insects in Western markets has been primarily discussed from an environmental perspective. Following advances in food technology and regulation, edible insects are an emerging research topic not only in environmental sciences, but also in consumer research. To contribute to this rising interest, the present research presents consumer psychological drivers to promote insect consumption based on research on social influence. Two experiments that assessed the influence of peer (Study 1) as well as expert influence (Study 2) on acceptance indicators suggest that both types of influence are significantly associated with acceptance of insects as foods. Study 2 further reveals that the proposed effect of expert influence on acceptance of insects is moderated by insect-based disgust sensitivity in a way that expert influence is stronger for consumers low in insect-based disgust sensitivity. Taken together, our research shows that managing expectations via social influence can be an important driver to increase the adoption of insects in Western markets.

Cathodal HD-tDCS above the left dorsolateral prefrontal cortex increases environmentally sustainable decision-making.

Environmental sustainability is characterized by a conflict between short-term self-interest and longer-term collective interests. Self-control capacity has been proposed to be a crucial determinant of people's ability to overcome this conflict. Yet, causal evidence is lacking, and previous research is dominated by the use of self-report measures. Here, we modulated self-control capacity by applying inhibitory high-definition transcranial current stimulation (HD-tDCS) above the left dorsolateral prefrontal cortex (dlPFC) while participants engaged in an environmentally consequential decision-making task. The task includes conflicting and low conflicting trade-offs between short-term personal interests and long-term environmental benefits. Contrary to our preregistered expectation, inhibitory HD-tDCS above the left dlPFC, presumably by reducing self-control capacity, led to more, and not less, pro-environmental behavior in conflicting decisions. We speculate that in our exceptionally environmentally friendly sample, deviating from an environmentally sustainable default required self-control capacity, and that inhibiting the left dlPFC might have reduced participants' ability to do so.

Neuroscientific approaches to study prosociality.

Prosociality is a core feature of human functioning and has been a topic of interest across disciplinary boundaries for decades. In this review, we highlight different neuroscientific approaches that have enriched traditional psychological methods for studying prosocial behavior among individuals and groups. First, we outline findings from task-based neuroimaging studies that provide correlational evidence for the involvement of different neural mechanisms in prosocial behavior. Next, we present different brain stimulation studies that show several brain areas to be causally related to prosocial behavior. Furthermore, we outline the task-independent neural trait approach that quantifies temporally stable brain-based characteristics in an effort to uncover sources of interindividual differences in prosocial preferences. We discuss how the findings from these approaches have contributed to our understanding of prosocial behavior and suggest directions for future research.

Mentalizing with the future: Electrical stimulation of the right TPJ increases sustainable decision-making.

While many people acknowledge the urgency to drastically change our consumption patterns to mitigate climate change, most people fail to live sustainably. We hypothesized that a lack of sustainability stems from insufficient intergenerational mentalizing (i.e., taking the perspective of people in the future). To causally test our hypothesis, we applied high-definition transcranial direct current stimulation (HD-tDCS) to the temporo-parietal junction (TPJ). We tested participants twice (receiving stimulation at the TPJ or the vertex as control), while they engaged in a behavioral economic paradigm measuring sustainable decision-making, even if sustainability was costly. Indeed, excitatory anodal HD-tDCS increased sustainable decision-making, while inhibitory cathodal HD-tDCS had no effect. These finding cannot be explained by changes in participants' fairness norms or their estimation of how other people would behave. Shedding light on the neural basis of sustainability, our results could inspire targeted interventions tackling the TPJ and give neuroscientific support to theories on how to construct public campaigns addressing sustainability issues.

Large but diminishing effects of climate action nudges under rising costs.

Behavioural public policy has received broad research attention, particularly in the domain of motivating pro-environmental behaviours. We investigate how far the efficacy of arguably one the most popular behavioural policy tools (green 'default change' nudges) depends on the associated cost. On the basis of a field study involving carbon offsets for over 30,000 flights booked by more than 11,000 airline customers, we show that green defaults have a large effect on voluntary climate action, even when several hundreds of Euros are at stake. The effect fully vanishes only as costs approach approximately €800.

When Utilitarian Claims Backfire: Advertising Content and the Uptake of Insects as Food.

A key challenge for climate change mitigation on the consumer side is to break habits that excessively lead to carbon emission. One of the culturally most robust human routines is the heavy reliance of the Western societies on conventional meat sources such as beef, pork, and poultry, which were recently accused of causing particularly high climate costs. In this light, the UN (FAO) has suggested the increasing use of insects as an alternative source of animal protein intended for human diets. Yet, insects have not reached the mainstream of Western cuisine. Currently, a frequent promotion strategy of insects is to highlight the Utilitarian benefits associated with their consumption (e.g., with respect to the environment or one's health). The present research addresses the efficacy of such claims in a consumer research study involving 180 participants recruited from the general population in Germany. Arguing based on social-cognitive research in the area of moral and environmental psychology, we hypothesized and found that a focus on beneficial, but temporally distant motives (e.g., health)-counterintuitively-decreases consumption in comparison to immediate, hedonic advertisements (e.g., tasty). Furthermore, our study provides process evidence suggesting pretrial expectations induced by a particular claim mediate the relationship between claims and consumption. Thus, the present research not only refutes a state-of-the-art approach in the promotion of insects as food, but also provides an alternative approach and process evidence by integrating psychological factors.