Quantifying the Value of Emotions Using a Willingness to Pay Approach

People generally seek out positive moods and avoid negative moods; however, it is unclear which motivation is more pronounced. Two studies addressed this issue by developing a value-based ranking of emotions based on the willingness to pay (WTP) approach. The approach utilizes money’s cardinal properties and assumes opportunity costs as with everyday purchases. In Study 1 British participants indicated they would be willing to pay more to experience positive than to avoid negative emotions. In Study 2 this positivity bias was replicated with another sample of British participants. However, Hong Kong Chinese participants did not show such a preference, and were willing to pay significantly less to experience positive emotions but more to avoid negative emotions when compared with British participants. Experiencing Love was given the highest WTP judgment in all samples. Thus, some emotions are universally valued, whereas preferences for others differ across cultural groups, perhaps shaped by norms. Implications concerning valuations of psychological states for policy purposes are discussed.     

Taï chimpanzees use botanical skills to discover fruit: what we can learn from their mistakes

Fruit foragers are known to use spatial memory to relocate fruit, yet it is unclear how they manage to find fruit in the first place. In this study, we investigated whether chimpanzees (Pan troglodytes verus) in the Taï National Park make use of fruiting synchrony, the simultaneous emergence of fruit in trees of the same species, which can be used together with sensory cues, such as sight and smell, to discover fruit. We conducted observations of inspections, the visual checking of fruit availability in trees, and focused our analyses on inspections of empty trees, so to say “mistakes”. Learning from their “mistakes”, we found that chimpanzees had expectations of finding fruit days before feeding on it and significantly increased inspection activity after tasting the first fruit. Neither the duration of feeding nor density of fruit-bearing trees in the territory could account for the variation in inspection activity, which suggests chimpanzees did not simply develop a taste for specific fruit on which they had fed frequently. Instead, inspection activity was predicted by a botanical feature—the level of synchrony in fruit production of encountered trees. We conclude that chimpanzees make use of the synchronous emergence of rainforest fruits during daily foraging and base their expectations of finding fruit on a combination of botanical knowledge founded on the success rates of fruit discovery, and a categorization of fruit species. Our results provide new insights into the variety of food-finding strategies employed by primates and the adaptive value of categorization capacities.     

Head-mounted displays for clinical virtual reality applications: pitfalls in understanding user behavior while using technology.

The use of virtual environments with head-mounted displays (HMDs) offers unique assets to the evaluation and therapy of clinical populations. However, research examining the effects of this technology on clinical populations is sparse. Understanding how wearers interact with the HMD is vital. Discomfort leads to altered use of the HMD that could confound performance measures; the very measures which might be used as tools for clinical decision making. The current study is a post-hoc analysis of the relationship between HMD use and HMD comfort. The analysis was conducted to examine contributing factors for a high incidence of simulator sickness observed in an HMD-based driving simulator. Pearson correlation analysis was used to evaluate objective and subjective measures of HMD performance and self-reported user comfort ratings. The results indicated weak correlations between these variables, indicating the complexity of quantifying user discomfort and HMD performance. Comparison of two case studies detailing user behavior in the virtual environment demonstrates that selected variables may not capture how individuals use the HMD. The validity and usefulness of the HMD-based virtual environments must be understood to fully reap the benefits of virtual reality (VR) in rehabilitation medicine.     

When Marcel Mauss’s <Emphasis Type="Italic">Essai sur le Don</Emphasis> becomes <Emphasis Type="Italic">The Gift</Emphasis>: variations on the theme of solidarity

Since the early 1970s, Marcel Mauss’s Essai sur le Don (1923), translated into English as The Gift in 1954, has been a standard reference in the social science and bioethical literature on the use of human body parts and substances for medical and research purposes. At that time, three social scientists—political scientist Richard Titmuss in the United Kingdom and sociologist Renée C. Fox working with historian Judith Swazey in the United States—had the idea of using this concept to highlight the fundamental structure of the biomedical practices they were studying, respectively, blood donation, and hemodialysis and organ transplantation. The fact that these first applications of Mauss’s essay should emerge in English- rather than in French-speaking countries raises the question of what the translation of the essay, and notably of the word don as gift, may have to do with this fact. Reading Mauss in translation undoubtedly inspired a seminal approach to interpreting medical and research practices based on bodily giving. This article posits that something may have also been lost: a much broader concept of giving with unquestionable links to the Durkheimian concept of solidarity, which Mauss conceptualizes not only as an obligation but also as a liberty to give.     

John Nash: The Sufferings of Those Who Loved Him

This article, as a sequel to three previous papers on John Nash by Capps (2003, 2004a, & 2004b), focuses on the other side of Nashs beautiful mind by examining the sufferings of those who loved him. Nashs mistress and wife, appear to have suffered the most by Nashs narcissistic and paranoid schizophrenic tendencies due to his noncommittal and disrespectful attitudes. Nashs exploitive and experiential ways of relating to his close male friends (special friendships) seemed to have caused much pain and agony in at least two of his special friends. In addition, Nashs two sons also suffered from his lack of affection and responsibility. Thus it is crucial for people in mental health professionals as well as in pastoral care and counseling not only to care for the mentally ill but also for those who are around him or her.     

Taï chimpanzees anticipate revisiting high-valued fruit trees from further distances

The use of spatio-temporal memory has been argued to increase food-finding efficiency in rainforest primates. However, the exact content of this memory is poorly known to date. This study investigated what specific information from previous feeding visits chimpanzees (Pan troglodytes verus), in Taï National Park, Côte d’Ivoire, take into account when they revisit the same feeding trees. By following five adult females for many consecutive days, we tested from what distance the females directed their travels towards previously visited feeding trees and how previous feeding experiences and fruit tree properties influenced this distance. To exclude the influence of sensory cues, the females’ approach distance was measured from their last significant change in travel direction until the moment they entered the tree’s maximum detection field. We found that chimpanzees travelled longer distances to trees at which they had previously made food grunts and had rejected fewer fruits compared to other trees. In addition, the results suggest that the chimpanzees were able to anticipate the amount of fruit that they would find in the trees. Overall, our findings are consistent with the hypothesis that chimpanzees act upon a retrieved memory of their last feeding experiences long before they revisit feeding trees, which would indicate a daily use of long-term prospective memory. Further, the results are consistent with the possibility that positive emotional experiences help to trigger prospective memory retrieval in forest areas that are further away and have fewer cues associated with revisited feeding trees.