Unexpected a posteriori necessary laws of nature

In this paper I argue that it is not a priori that all the laws of nature are contingent. I assume that the fundamental laws are contingent and show that some non-trivial, a posteriori, non-basic laws may nonetheless be necessary in the sense of having no counterinstances in any possible world. I consider a law L_S (such as ‘salt dissolves in water’) that concerns a substance S. Kripke's arguments concerning constitution show that the existence of S requires that a certain deeper level law or variants thereof hold. At the same time, that law and its variants may each entail the truth of L_S. Thus the existence of S entails L_S. Consequently there is no world in which S exists and fails to obey L_S. I consider the conditions concerning the fundamental laws that would make this phenomenon ubiquitous. I conclude with some consequences for metaphysics.     

Dynamic mechanisms of exercise to improve body satisfaction: Perceived or actual fat loss?

We examined the dynamic mechanisms of aerobic training (AT) and strength training (ST) to improve body satisfaction. Sixty-six participants were randomised to either the AT or ST condition and completed an 8-week intervention. Participants completed 3 weekly, 30-minute sessions of moderate intensity AT (65–75% VO₂max) or ST (65–75% 1-RM). The energy consumption of each session was approximately equivalent under both conditions. Body satisfaction, body composition, perceived fitness and exercise self-efficacy were measured at baseline and biweekly during the intervention. Exercise improved individuals' body satisfaction (p < .05). When the energy expenditures of AT and ST were equal, there was no difference in body satisfaction improvement. There were dynamic mechanisms underlying the effects of exercise on body satisfaction. Specifically, perceived fitness influenced body satisfaction improvements during the early stages of the exercise program, while changes in body composition influenced body satisfaction toward the end of the exercise program. There were sex differences in the mechanisms underlying body satisfaction. For women, perceived fat was more important in the early intervention period; for men, actual body fat was more valuable in the late intervention period. An effective strategy to improve body satisfaction is to initially target perceived fitness before focusing on changing body composition.     

Tool-use and instrumental learning in the Eurasian jay (<Emphasis Type="Italic">Garrulus glandarius</Emphasis>)

Recent research with Rooks has demonstrated impressive tool-using abilities in captivity despite this species’ classification as a non-tool-user in the wild. Here, we explored whether another non-tool-using corvid, the Eurasian Jay, would be capable of similar feats and investigated the relative contributions of causal knowledge and instrumental conditioning to the birds’ performance on the tasks. Five jays were tested on a variety of tasks involving water displacement. Two birds reliably interacted with the apparatuses. In these tasks, both birds showed a preference for inserting stones into a tube containing liquid over a tube containing a solid or a baited ‘empty’ tube and also for inserting sinkable items over non-sinkable items into a tube of water. To investigate the contribution of instrumental conditioning, subjects were then tested on a series of tasks in which different cues were made available. It was found that, in the absence of any apparent causal cues, these birds showed a clear preference for the rewarded tube when the food incrementally approached with every stone insertion, but not when it simply “appeared” after the correct number of stone insertions. However, it was found that subjects did not prefer to insert stones into a tube rewarded by the incremental approach of food if the available causal cues violated the expectations created by existing causal knowledge (i.e. were counter-intuitive). An analysis of the proportion of correct and incorrect stone insertions made in each trial across tasks offering different types of information revealed that subjects were substantially more successful in experiments in which causal cues were available, but that rate of learning was comparable in all experiments. We suggest that these results indicate that Eurasian jays use the incremental approach of the food reward as a conditioned reinforcer allowing them to solve tasks involving raising the water level and that this learning is facilitated by the presence of causal cues.     

Training social cognition: from imitation to Theory of Mind

Evidence for successful socio-cognitive training in typical adults is rare. This study attempted to improve Theory of Mind (ToM) and visual perspective taking in healthy adults by training participants to either imitate or to inhibit imitation. Twenty-four hours after training, all participants completed tests of ToM and visual perspective taking. The group trained to inhibit their tendency to imitate showed improved performance on the visual perspective-taking test, but not the ToM test. Neither imitation training, nor general inhibition training, had this effect. These results support a novel theory of social cognition suggesting that the same self-other discrimination process underlies imitation inhibition and perspective taking. Imitation, perspective taking and ToM are all pro-social processes--ways in which we reach out to others. Therefore, it is striking that perspective taking can be enhanced by suppressing imitation; to understand another, sometimes we need, not to get closer, but to pull away.     

Transdermal nicotine during cue reactivity in adult smokers with and without anxiety disorders

Transdermal nicotine almost doubles tobacco cessation rates; however, little is known about what happens to smokers during the quit process when they are wearing the nicotine patch and are confronted with high-risk smoking triggers. This is particularly important for smokers with psychological disorders who disproportionately represent today's smokers and have more trouble quitting. Using a mixed between- and within-subjects design, smokers with anxiety disorders (n = 61) and smokers without any current Axis I disorders (n = 38) received transdermal nicotine (21 mg) or a placebo patch over two assessment days separated by 48 hr. Urge to smoke was evaluated during a 5-hr patch absorption period (reflecting general smoking deprivation) and during imaginal exposure to theoretically high-risk triggers containing smoking cues, anxiety cues, both, or neutral cues. No differences were observed between smokers with and without anxiety disorders. Significant Patch × Time and Patch × Cue Content interactions were found. Both patch conditions experienced an increase in urge during the deprivation period, but postabsorption urge was significantly higher in the placebo condition, suggesting that transdermal nicotine attenuated the degree to which urge to smoke increased over time. During the cue reactivity trials, when participants received the nicotine patch, they experienced significantly lower urge in response to both smoking-only and neutral cues, but not when anxiety cues were present (alone or in combination with smoking cues). These data suggest that transdermal nicotine alleviates urge only under certain circumstances and that adjunctive interventions are likely necessary to address smoking urges in response to spikes in distress among smokers trying to quit. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

Editors’ Overview: Neuroethics: Many Voices and Many Stories

Advances in neuroscience continue to enhance understanding of the brain and provide new tools to take advantage of that understanding. These changes are poised to profoundly alter society. Given that the impact will be felt not only by neuroscientists, but by diverse members of society, it is imperative that conversations engage all stakeholders. Doing so will allow for the sharing of diverse views and perspectives to understand and frame the science, better educate and prepare the public for new developments, and provide a shared approach to identifying and resolving ethical challenges. These were the goals of Neuroethics Week, staged in 2007 by the Center for Ethics in Science and Technology in San Diego, and are the basis for the contributions to this special issue of Science and Engineering Ethics.