Lateralized scratching in chimpanzees (Pan troglodytes): Evidence of a functional asymmetry during arousal

This study evaluated laterality in scratching by chimpanzees (n = 89) during socially arousing circumstances. Hand use and the side of the body scratched was recorded during a baseline and experimental condition. In the experimental condition, chimpanzees were shown a video of other conspecifics sharing, fighting over, and consuming a watermelon. Self-touches were categorized as either rubs or scratches. The chimpanzees showed a significant right hand bias for rubbing and also significantly directed the rubs to the right side of the body. For scratching, the chimpanzees showed no hand preference but a significant bias for scratching on the left side of the body. These results support the view that the right hemisphere regulates the autonomic nervous system during arousal.     

The environment influences whether high-fat foods are associated with palatable or with unhealthy

This study investigated whether relatively automatic evaluations of food differ between situations and between obese people and lean controls. These evaluations were assessed in the affective priming paradigm (APP) -- a response latency based measure for associations. In Experiment 1, we either focused participants (33 obese and 26 lean controls) on the palatability (restaurant condition) or on the healthiness (health condition) of food, prior to the APP. Independent of weight-status, relatively automatic evaluations of food were based on palatability in the restaurant condition, and on health in the health condition. So, the current focus of attention can shape the way foods are evaluated relatively automatically. In Experiment 2, craving was induced in participants (27 obese and 29 lean controls). Unexpectedly, the craving induction did not achieve its goal of focusing on the palatability of food in general, but just for low-fat foods, possibly because of the health-emphasizing environment -- a hospital. Interestingly, obese people showed a stronger palatability priming effect with increasing levels of initial craving. For normal weight controls the effect was in the same direction, but missed significance. In our environment, palatability of food may be too salient, and health may not be salient enough, influencing automatic food-evaluations.     

What is the relationship between synaesthesia and visuo-spatial number forms?

This study compares the tendency for numerals to elicit spontaneous perceptions of colour or taste (synaesthesia) with the tendency to visualise numbers as occupying particular visuo-spatial configurations (number forms). The prevalence of number forms was found to be significantly higher in synaesthetes experiencing colour compared both to synaesthetes experiencing taste and to control participants lacking any synaesthetic experience. This suggests that the presence of synaesthetic colour sensations enhances the tendency to explicitly represent numbers in a visuo-spatial format although the two symptoms may nevertheless be logically independent (i.e. it is possible to have number forms without colour, and coloured numbers without forms). Number forms are equally common in men and women, unlike previous reports of synaesthesia that have suggested a strong female bias. Individuals who possess a number form are also likely to possess visuo-spatial forms for other ordinal sequences (e.g. days, months, letters) which suggests that it is the ordinal nature of numbers rather than numerical quantity that gives rise to this particular mode of representation. Finally, we also describe some consequences of number forms for performance in a number comparison task.     

Some effects of stimulant medication on response allocation: a double-blind analysis

Children who are diagnosed with attention deficit hyperactivity disorder (or who engage in behavior consistent with such a diagnosis) are often prescribed stimulant medications for hyperactive or inattentive behaviors. However, the mechanisms by which stimulant medications affect individuals' behavior are rarely evaluated. The purpose of the current study was to evaluate the effects of stimulant medication on response allocation when antecedents and consequences were held constant and equated. Results indicated that the presence of an amphetamine medication (Adderall) influenced response allocation across two concurrently available responses while all other stimulus conditions were held constant.     

The siren's call: terror management and the threat of men's sexual attraction to women

Why do sexually appealing women often attract derogation and aggression? According to terror management theory, women's sexual allure threatens to increase men's awareness of their corporeality and thus mortality. Accordingly, in Study 1 a subliminal mortality prime decreased men's but not women's attractiveness ratings of alluring women. In Study 2, mortality salience (MS) led men to downplay their sexual intent toward a sexy woman. In Study 3, MS decreased men's interest in a seductive but not a wholesome woman. In Study 4, MS decreased men's but not women's attraction to a sexy opposite-sex target. In Study 5, MS and a corporeal lust prime increased men's tolerance of aggression toward women. Discussion focuses on mortality concerns and male sexual ambivalence.