Bias produced by fast guessing in distribution-based tests of race models.

A comparison involving cumulative probability distributions of reaction time (RT) has been used to test race models of the redundancy gain observed in certain divided-attention paradigms. It has been pointed out, however, that the presence of fast guesses would interfere with this test, biasing it to accept race models. The present paper reports simulations carried out to determine the size of the bias introduced by fast guesses. In absolute terms, this bias can be quite large--exceeding 175 msec in some conditions. Simulations indicate that the bias increases with the percentage of fast guesses and with the latency difference between the lower tails of guess and nonguess RT distributions. Discarding and rerunning errors reduces bias somewhat, but a more elaborate "kill-the-twin" procedure reduces it much more.     

Measures of temporal discrimination in fixed-interval performance: a case study in archiving data.

The primary data of many experimental studies of animal learning and performance consist of the times at which stimuli and reinforcers were delivered, and the times at which responses occurred. The articles based on most of these studies report selected data, either from some sessions or some animals, or summary measures of the animals' behavior. The primary data are sufficient to produce any of the selected and summary measures, but the selected and summarized data cannot produce many of the measures used in other experimental reports. It is now feasible to archive the primary data from animal behavior experiments so that they are accessible for others to perform secondary analysis. The value of such secondary analysis of archived data is described with a case study in which rats were trained on three fixed-interval schedules of reinforcement. The full data set may be downloaded from www.psychonomic.org/archive/.     

Unplanned pregnancy and risk of maternal depression: secondary data analysis from a prospective pregnancy cohort

Purpose: to evaluate the relationship between unplanned pregnancy (UP), a common problem in high and low income countries and maternal depression (MD). Methods: Secondary analysis of data from a prospective cohort study with pregnant women recruited from 10 primary care clinics of the public sector in São Paulo, Brazil. Participants were questioned about pregnancy intention at 20–30 weeks of gestation. The Self Report Questionnaire score >7 was used to evaluated the presence of depression during pregnancy and 11 months after childbirth. Four groups of MD were defined: never; antenatal only; postnatal only; persistent (both antenatal/postnatal). Multinomial logistic regression was used to assess the relationship between UP and MD, controlling for confounding. Results: Data were analysed for 701 at the postpartum period. Five hundred and sixty-two (67.8%) women did not plan the pregnancy. Women with UP had 2.5 more risk of being depressed during both assessments (during pregnancy and postpartum) when compared to women with a planned pregnancy (RR: 2.5; 95% CI: 1.47:4.30). In the adjusted models, women with UP were significantly more likely to have persistent depression (RR: 2.3; 95% CI: 1.2:4.3). Conclusion: UP is an independent risk factor for persistent depression, but not for postpartum depression     

Daily Uplifts,Well-Being and Performance in Organizational Settings: The Differential Mediating Roles of Affect and Work Engagement

Affective events theory suggests that affective events at work arouse emotional reactions that influence employees’ attitudes and behaviour in the workplace. In the present study, we apply this theoretical framework to clarify the interplay of variables that explain well-being and performance. We analysed the mediating role of positive affect and work engagement between daily uplifts and well-being, and between daily uplifts and performance. Results from a sample of 293 employees revealed that daily uplifts were positively associated with well-being and performance. While the effects of daily uplifts on well-being were fully mediated by positive affect and work engagement, the effects of daily uplifts on performance were only partially mediated by positive affect and work engagement. In both cases, the effect of positive affect was bigger than that of work engagement. The relations explored provide new theoretical elements for models that explain which variables influence well-being and performance in organizational contexts. The implications for employee health and organizational success are discussed.     

Human biological and nonbiological point-light movements: Creation and validation of the dataset

Human action perception is so powerful that people can identify movement efficiently in the absence of pictorial information, such as in point-light displays. Interest is growing in this type of stimulus for research in neuroscience. This interest stems from the advantage of separating the component of pure human action kinematics from other pictorial information, such as facial expression and muscle contraction. Although several groups have previously developed datasets of human point-light actions, due to the lack of datasets composed of daily actions with short durations, we developed 20 biological and 40 control (scrambled) point-light movements by using the technique of recording people wearing reflector patches. The videos are about 1 s long. Subsequently, we performed a judgment task in which 100 participants (50 male and 50 female) evaluated each video according to three categories: human action resemblance, performed action, and gender of actor. We present the mean scores of each evaluation for each video, and further propose a selection of the most suitable videos to be used as human point-light action displays and scrambled point-light displays for control. Finally, we discuss our findings on the gender attributions of the point-light displays.     

Vestibular stimulation interferes with the dynamics of an internal representation of gravity

The remembered vanishing location of a moving target has been found to be displaced downward in the direction of gravity (representational gravity) and more so with increasing retention intervals, suggesting that the visual spatial updating recruits an internal model of gravity. Despite being consistently linked with gravity, few inquiries have been made about the role of vestibular information in these trends. Previous experiments with static tilting of observers’ bodies suggest that under conflicting cues between the idiotropic vector and vestibular signals, the dynamic drift in memory is reduced to a constant displacement along the body’s main axis. The present experiment aims to replicate and extend these outcomes while keeping the observers’ bodies unchanged in relation to physical gravity by varying the gravito-inertial acceleration using a short-radius centrifuge. Observers were shown, while accelerated to varying degrees, targets moving along several directions and were required to indicate the perceived vanishing location after a variable interval. Increases of the gravito-inertial force (up to 1.4G), orthogonal to the idiotropic vector, did not affect the direction of representational gravity, but significantly disrupted its time course. The role and functioning of an internal model of gravity for spatial perception and orientation are discussed in light of the results.     

The morality of harm

In this article, we discuss the range of concerns people weigh when evaluating the acceptability of harmful actions and propose a new perspective on the relationship between harm and morality. With this aim, we examine Kelly, Stich, Haley, Eng and Fessler’s [Kelly, D., Stich, S., Haley, K., Eng, S., & Fessler, D. (2007). Harm, affect, and the moral/conventional distinction. Mind and Language, 22, 117-131] recent claim that, contrary to Turiel and associates, people do not judge harm to be authority independent and general in scope in the context of complex harmful scenarios (e.g., prisoner interrogation, military training). In a modified replication of their study, we examined participants’ judgments of harmful actions in these contexts by taking into account their explanations for their judgments. We claim that both in terms of participants’ judgments and rationales, the results largely confirm our hypothesis that actions involving harm andinjustice or rights violation are judged to be authority independent and general in scope, which is a modification of Turiel’s traditional hypothesis.