Real three-dimensional objects: effects on mental rotation

The current experiment investigated real three-dimensional (3D) objects with regard to performance on a mental rotation task and whether the appearance of sex differences may be mediated by experiences with spatially related activities. 40 men and 40 women were presented with alternating timed trials consisting of real-3D objects or two-dimensional illustrations of 3D objects. Sex differences in spatially related activities did not significantly influence the finding that men outperformed women on mental rotation of either stimulus type. However, on measures related to spatial activities, self-reported proficiency using maps correlated positively with performance only on trials with illustrations whereas self-reported proficiency using GPS correlated negatively with performance regardless of stimulus dimensionality. Findings may be interpreted as suggesting that rotating real-3D objects utilizes distinct but overlapping spatial skills compared to rotating two-dimensional representations of 3D objects, and real-3D objects can enhance mental rotation performance.     

Number of players who gain ball possession as a function of basketball mass among 9-11-year-old male players

This study analyzed whether a ball with a higher (540-g) or lower (440-g) mass than the regulation ball (485-g) resulted in a larger number of participants gaining ball possession during games. Prior studies have indicated that ball handling is facilitated by decreasing the mass of the ball. It was assumed that a greater number of children gaining possession of the ball indicated greater ease of use and more control. Thus, the hypothesis was that the number of participants who gained ball possession would increase when using a ball of lower mass. The participants were 54 boys from six youth basketball teams. Participants played four games with each one of the three different balls and the number of possessions was calculated using videos of each game. The hypothesis was only partially supported: the number of participants who gained possession with the regular ball was similar to that with the 440-g ball and with the 540-g ball, but a greater number of participants gained possession with the 440-g ball in comparison to the 540-g ball. This result suggests balls that differ by more than 65 g may affect actual game outcomes.     

Frequency of lucid dreaming in a representative German sample

Lucid dreams occur when a person is aware that he is dreaming while he is dreaming. In a representative sample of German adults (N = 919), 51% of the participants reported that they had experienced a lucid dream at least once. Lucid dream recall was significantly higher in women and negatively correlated with age. However, these effects might be explained by the frequency of dream recall, as there was a correlation of .57 between frequency of dream recall and frequency of lucid dreams. Other sociodemographic variables like education, marital status, or monthly income were not related to lucid dream frequency. Given the relatively high prevalence of lucid dreaming reported in the present study, research on lucid dreams might be pursued in the sleep laboratory to expand the knowledge about sleep, dreaming, and consciousness processes in general.     

Dynamic adaptation to history of trial difficulty explains the effect of congruency proportion on masked priming

In reaction time research, there has been an increasing appreciation that response-initiation processes are sensitive to recent experience and, in particular, the difficulty of previous trials. From this perspective, the authors propose an explanation for a perplexing property of masked priming: Although primes are not consciously identified, facilitation of target processing by a related prime is magnified in a block containing a high proportion of related primes and a low proportion of unrelated primes relative to a block containing the opposite mix (Bodner & Masson, 2001). In the present study, this phenomenon is explored with a parity (even/odd) decision task in which a prime (e.g., 2) precedes a target that can be either congruent (e.g., 4) or incongruent (e.g., 3). It is shown that the effect of congruence proportion with masked primes cannot be explained in terms of the blockwise prime-target contingency. Specifically, with masked primes, there is no congruency disadvantage in a block containing a high proportion of incongruent primes, but there is a congruency advantage when the block contains an equal proportion of congruent and incongruent primes. In qualitative contrast, visible primes are sensitive to the blockwise prime-target contingency. The authors explain the relatedness proportion effect found with masked primes in terms of a model according to which response-initiation processes adapt to the statistical structure of the environment, specifically the difficulty of recent trials. This account is supported with an analysis at the level of individual trials using the linear mixed effects model.     

A group construal account of drop-in-the-bucket thinking in policy preference and moral judgment

Decisions, both moral and mundane, about saving individuals or resources at risk are often influenced not only by numbers saved and lost, but also by proportions of groups saved and lost. Consider choosing between a program that saves 60 of 240 lives at risk and one that saves 50 of 100. The first option maximizes absolute number saved; the second, proportion saved. In two studies, we show that the influence of proportions on such decisions depends on how items at risk are mentally represented. In particular, we show that proportions have greater influence on people's decisions to the extent that the items at risk are construed as forming groups, as opposed to distinct individuals. Construal was manipulated by means of animated displays in which resources at risk moved either independently (promoting individual construal) or jointly (promoting group construal). Results support the hypothesis that (a) decision makers form mental representations which vary in the degree to which resources at risk are construed as groups versus individuals and (b) construal of resources as groups promotes the influence of proportions on decisions and moral judgments.     

The bystander-effect: a meta-analytic review on bystander intervention in dangerous and non-dangerous emergencies

Research on bystander intervention has produced a great number of studies showing that the presence of other people in a critical situation reduces the likelihood that an individual will help. As the last systematic review of bystander research was published in 1981 and was not a quantitative meta-analysis in the modern sense, the present meta-analysis updates the knowledge about the bystander effect and its potential moderators. The present work (a) integrates the bystander literature from the 1960s to 2010, (b) provides statistical tests of potential moderators, and (c) presents new theoretical and empirical perspectives on the novel finding of non-negative bystander effects in certain dangerous emergencies as well as situations where bystanders are a source of physical support for the potentially intervening individual. In a fixed effects model, data from over 7,700 participants and 105 independent effect sizes revealed an overall effect size of g = -0.35. The bystander effect was attenuated when situations were perceived as dangerous (compared with non-dangerous), perpetrators were present (compared with non-present), and the costs of intervention were physical (compared with non-physical). This pattern of findings is consistent with the arousal-cost-reward model, which proposes that dangerous emergencies are recognized faster and more clearly as real emergencies, thereby inducing higher levels of arousal and hence more helping. We also identified situations where bystanders provide welcome physical support for the potentially intervening individual and thus reduce the bystander effect, such as when the bystanders were exclusively male, when they were naive rather than passive confederates or only virtually present persons, and when the bystanders were not strangers.     

Facilitated attentional disengagement from negative information in relation to self-reported depressive symptoms of Dutch female undergraduate students

Prior research has shown that depressive symptoms are associated with an enhanced attention toward negative stimuli and difficulty of disengaging attention from negative stimuli. The current study was an extension of a 2005 study by Koster and colleagues. A different stimulus presentation time and word set were used. The whole range of depressive symptoms was included in this sample instead of creating dichotomized groups. The Exogenous Cueing Task with negative, positive, and neutral cues was administered to 85 female undergraduate university students. Participants completed the Beck's Depression Inventory-II-NL questionnaire to measure self-reported depression. Contrary to previous findings, depressive symptoms were related to a facilitated rather than impaired attentional disengagement from negative stimuli. An explanation for the discrepancy with findings from Koster, et al. may be the different stimulus presentation time (1000 msec. instead of 500 or 1500 msec.).     

Evaluating a brief measure of social self-efficacy among U.S. adolescents

Preliminary data were collected to evaluate the performance of a social self-efficacy measure among 4,061 public high school adolescents. Principal-axis factor analysis was followed by a 4-way between-groups analysis of variance (ANOVA) to test for differences in the Total score means on selected demographic estimates and their interactions. Relations between the Total score and selected risk behaviors were examined through a series of one-way ANOVAs and the Tukey HSD test. Factor analysis results suggested a one-factor model best explained the factor structure of the scale items (factor loading range = .64 - .77, eigenvalue = 4.05, h(2) = .51). Females reported a significantly higher mean Total social self-efficacy rating than males, while White students reported a significantly higher mean Total social self-efficacy rating than Black and Asian students. Statistically significant lower mean Total social self-efficacy ratings were also noted for those who reported physical fighting, avoiding school, and being bullied.