Judging and actualizing intrapersonal and interpersonal affordances

The current study investigated the perception of intrapersonal, interpersonal, and tool-based grasping possibilities. In Experiment 1, participants judged whether they would grasp planks of wood-presented in ascending, descending, and random orders of length-using one hand (1H), two hands (2H), or with a tool that extended their reach (TH). In Experiment 2, participants physically grasped the planks using 1H, 2H, or TH. In Experiments 3 and 4, the choice of TH was replaced with a choice of grasping the planks with another person (2P). The results showed that presentation order influenced the participants' behavior differently in the judgment and action experiments. The same behavioral patterns, however, were observed when participants switched between 1H and 2H, 2H and TH, and 2H and 2P grasping. The point at which participants judged they would switch between the different modes of grasping, as well as the point at which participants physically switched between the grasping modes, occurred at similar action-scaled ratios. The equivalence of perceiving intrapersonal and interpersonal affordances is discussed.     

Reference Points and Omission Bias

Subjects were asked to evaluate the choice of options leading to known outcomes, or to say how they would feel about a chance outcome, in hypothetical decisions. We independently manipulated the value of the status quo and the assignment of the better or worse outcome to an act or an omission. Acts leading to the worse outcome were always considered worse than omissions leading to the worse outcome. This act-omission difference was reduced or reversed for the better outcome. Most experiments showed an overall bias toward omissions (combining better and worse). Little evidence was found for greater omission bias for losses relative to the status quo than for gains. A bias toward maintaining the status quo itself was found, however, independently of omission bias. Most of the results can be explained by norm theory and by loss aversion, but other possible accounts are inconsistent with the results.     

Back to the Unchanging Past

The standard philosophical view of time travel has it that time travelers cannot change the past. It has been argued by some that the standard view is false, and that this can be shown using a two‐dimensional model of time. I defend the standard view against this attack. I show, first, that the addition of a second temporal dimension does not provide a model of changing the past and, second, that neither does the addition of n temporal dimensions for any n > 1.     

Epistemic Circularity Squared? Skepticism about Common Sense

Epistemic circularity occurs when a subject forms the belief that a faculty F is reliable through the use of F. Although this is often thought to be vicious, externalist theories generally don't rule it out. For some philosophers, this is a reason to reject externalism. However, Michael Bergmann defends externalism by drawing on the tradition of common sense in two ways. First, he concedes that epistemically circular beliefs cannot answer a subject's doubts about her cognitive faculties. But, he argues, subjects don't have such doubts, so epistemically circular beliefs are rarely called upon to play this role. Second, following Thomas Reid, Bergmann argues that we have noninferential, though epistemically circular, knowledge that our faculties are reliable. I argue, however, that Bergmann's view is undermined by doubts a subject should have and that there is no plausible explanation for how we can have noninferential knowledge that our faculties are reliable.     

The Power of Social Influence on Estimation Accuracy

Research shows that crowds can provide more accurate estimates of uncertain quantities than individuals (Surowiecki, 2004). But little is known about how to organize crowd members to maximize accuracy. When should crowd members work independently, and when should they work collaboratively? We examined the effects of social influence on estimation accuracy, consensus, and confidence. Participants first made independent estimates of uncertain quantities, such as the percentage of U.S. deaths due to heart attacks or the height of the tallest building. Then, in some conditions, they interacted with others online. After the discussion, they made second independent estimates. Social interaction improved accuracy. Despite well‐known problems with groups, such as herding and free riding, discussion resulted in more accurate estimates and greater consensus relative to independent estimates. We offer a simple model that describes the process by which group discussion improves the estimates of uncertain quantities. Copyright © 2014 John Wiley & Sons, Ltd.     

Correlations of trait and state emotions with utilitarian moral judgements

In four experiments, we asked subjects for judgements about scenarios that pit utilitarian outcomes against deontological moral rules, for example, saving more lives vs. a rule against active killing. We measured trait emotions of anger, disgust, sympathy and empathy (the last two in both specific and general forms, the latter referring to large groups of people), asked about the same emotions after each scenario (state emotions). We found that utilitarian responding to the scenarios, and higher scores on a utilitarianism scale, were correlated negatively with disgust, positively (but weakly and inconsistently) with anger, positively with specific sympathy and state sympathy, and less so with general sympathy or empathy. In a fifth experiment, we asked about anger and sympathy for specific outcomes, and we found that these are consistently predictive of utilitarian responding.     

Neuropsychological functioning in early hydrocephalus: review from a developmental perspective.

Children with hydrocephalus have deficits in several neuropsychological domains. The most notable are motor, visuoperceptual, and visuomotor function. These deficits are multiply determined and depend on the etiology and severity of the hydrocephalus to a large extent. Corpus callosum abnormalities resulting from stretching of callosal fibers and other cortical white matter tracts are implicated as contributory to these deficits. Enlarged ventricles and associated compression of posterior cortical areas also correlate with cognitive impairment. Distinguishing which cognitive domain negatively impacts on the child's functioning and which domains influence behavior in isolation or in combination has been the subject of numerous studies. Developmentally, we know little about the emergence of neuropsychological functioning in children with hydrocephalus. Study of the effects of hydrocephalus at different stages of development is useful to clinicians and researchers interested in the impact of diffuse neurophysiological damage on cognition in the developing brain. The medical and neuropsychological literature have begun to inform about these effects. The core deficits in hydrocephalus have yet to be explicated and a focus on investigations that answer these questions is required. This review summarizes the current knowledge about neurocognitive sequelae of hydrocephalus.