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Eating decisions depend on both appetitive and social motivation processes but the interactions between these motivations are poorly understood. We examine how women from nonclinical and clinical samples with variable levels of eating restriction make value-based decisions during an experimental task where monetary values are coupled with values related to body appearance, such as the social value of thinness. We show that eating restriction is associated with less risk taking and greater hesitancy when making decisions, but this general tendency is modulated by subjective body-related valuations in both subclinical and clinical samples; risk taking is decreased and hesitancy is increased when monetary reward is coupled with larger body stimuli, particularly in ‘at risk’ samples, and the reverse when reward is coupled with thinner body stimuli, particularly in clinical samples. Computational modelling further indicated that these behaviours are driven by an aversion to risk rather than loss, with desirable body outcomes being associated with less risk aversion, and undesirable body outcomes linked to greater risk aversion. These findings have important implications for current explanations of eating, indicating that cognitive and social factors may influence eating decisions by distinct mechanisms.

Traditional conceptions of peripersonal space emphasised its role in the organisation of skilled action. However, two other aspects of this representation have also been highlighted, namely, its defensive and social aspects. Indeed, having a distinct representation of the space close to the body is crucial for preparing defensive responses to noxious or threatening stimuli. Furthermore, it has been shown that peripersonal space is modulated by social factors. In this chapter, we will discuss these differing conceptions of peripersonal space. Evidence from several lines of research has revealed specialised neural and perceptual mechanisms for representing the space around the body for the defense of the body surface, including ethological and neurophysiological studies in animals, psychophysical studies showing perceptual mechanisms specialised for threatening classes of stimuli, and modulation of perception by specific fears. We will review studies on the motor function of peripersonal space and its role in guiding voluntary object-oriented actions. Recent studies have investigated the neural basis of the social aspect of peripersonal space both in monkey and humans. Finally, we will end by discussing the connection between action-based, defensive and social functions of peripersonal space.

ime-to-collision (TTC) underestimation has been interpreted as an adaptive response that allows observers to have more time to engage in a defensive behaviour. This bias seems, therefore, strongly linked to action preparation. There is evidence that the observer’s physical fitness modulates the underestimation effect so that people who need more time to react (i.e., those with less physical fitness) show a stronger underestimation effect. Here we investigated whether this bias is influenced by the momentary action capability of the observers. In the first experiment, participants estimated the time-to-collision of threatening or non-threatening stimuli while being mildly immobilized (with a chin-rest) or while standing freely. Having reduced the possibility of movement led participants to show more underestimation of the approaching stimuli. However, this effect was not stronger for threatening relative to non-threatening stimuli. The effect of the action capability found in the first experiment could be interpreted as an expansion of peripersonal space (PPS). In the second experiment, we thus investigated the generality of this effect using an established paradigm to measure the size of peripersonal space. Participants bisected lines from different distances while in the chin-rest or standing freely. The results replicated the classic left-to-right gradient in lateral spatial attention with increasing viewing distance, but no effect of immobilization was found. The manipulation of the momentary action capability of the observers influenced the participants’ performance in the TTC task but not in the line bisection task. These results are discussed in relation to the different functions of PPS.

Working Paper

By weaving together the fields of health economics, industrial organisation and industrial development, this book describes the benefits of promoting a country’s health industry as a way of stimulating its high-technology industrial capacity. The authors illustrate that the development of a country’s health industry not only improves the country’s health status, but also promotes an industry with relatively stable, high-wage employment, creates the potential for exporting goods and services, and produces scientific spillovers that will favourably impact other high-technology industries.