Zero the hero: Evidence for involvement of the ventromedial prefrontal cortex in affective bias for free items.

Recent evidence from psycho-economics shows that when the price of an item decreases to the extent that it becomes available for free, one can observe a remarkable increase of subjective utility toward this item. This phenomenon, which is not observed for any other price but zero, has been termed the zero-price effect (ZPE). The ZPE is attributed to an affective heuristic where the positive affect elicited by the free status of an item provides a mental shortcut biasing choice towards that item.

Experiential values are underweighted in decisions involving symbolic options.

Standard models of decision-making assume each option is associated with subjective value, regardless of whether this value is inferred from experience (experiential) or explicitly instructed probabilistic outcomes (symbolic). In this study, we present results that challenge the assumption of unified representation of experiential and symbolic value. Across nine experiments, we presented participants with hybrid decisions between experiential and symbolic options.

Motor Coordination and Strategic Cooperation in Joint Action.

Naturalistic joint action between two agents typically requires both motor coordination and strategic cooperation. However, these two fundamental processes have systematically been studied independently. We presented 50 dyads of adult participants with a novel collaborative task that combined different levels of motor noise with different levels of strategic noise, to determine whether the sense of agency (the experience of control over an action) reflects the interplay between these low-level (motor) and high-level (strategic) dimensions.

Quantity-quality trade-off in the acquisition of token preference by capuchin monkeys ( spp.).

Money represents a cornerstone of human modern economies and how money emerged as a medium of exchange is a crucial question for social sciences. Although non-human primates have not developed monetary systems, they can estimate, combine and exchange tokens. Here, we evaluated quantity-quality trade-offs in token choices in tufted capuchin monkeys as a first step in the investigation of the generalizability of tokens as reinforcers, which is a potentially relevant factor underlying the emergence of money in humans.

The adaptive value of probability distortion and risk-seeking in macaques' decision-making.

In humans, the attitude toward risk is not neutral and is dissimilar between bets involving gains and bets involving losses. The existence and prevalence of these decision features in non-human primates are unclear. In addition, only a few studies have tried to simulate the evolution of agents based on their attitude toward risk.