The effects of age and set size on the fast extraction of egocentric distance

ABSTRACT

Angular direction is a source of information about the distance to floor-level objects that can be extracted from brief glimpses (near one's threshold for detection). Age and set size are two factors known to impact the viewing time needed to directionally localize an object, and these were posited to similarly govern the extraction of distance. The question here was whether viewing durations sufficient to support object detection (controlled for age and set size) would also be sufficient to support well-constrained judgments of distance. Regardless of viewing duration, distance judgments were more accurate (less biased towards underestimation) when multiple potential targets were presented, suggesting that the relative angular declinations between the objects are an additional source of useful information. Distance judgments were more precise with additional viewing time, but the benefit did not depend on set size and accuracy did not improve with longer viewing durations. The overall pattern suggests that distance can be efficiently derived from direction for floor-level objects. Controlling for age-related differences in the viewing time needed to support detection was sufficient to support distal localization but only when brief and longer glimpse trials were interspersed. Information extracted from longer glimpse trials presumably supported performance on subsequent trials when viewing time was more limited. This outcome suggests a particularly important role for prior visual experience in distance judgments for older observers.     

“Toxin handling” and well-being: The case of the human resources manager

This study uses the job demands–resources model and multiple role theory to gain an understanding of the “toxin handling–well-being” relationship. “Toxin handlers” are empathetic managers willing to try to address pain and suffering in organizations (Frost, 2007). We use data from semistructured, in-depth interviews with HR managers to investigate the impact of the toxin handling role on well-being. The interviews indicate that toxin handling does not necessarily lead to the toxin handler’s ill health, because factors such as organizational and personal resources can influence that relationship. Further, toxin handlers can face very different toxin handling demands. These differences in the toxin handler’s resources and demands can lead to the full spectrum of possible health consequences of toxin handling (from decreased to enhanced health) for different toxin handlers.     

Energetic Cost and Stability during Human Walking at the Preferred Stride Frequency

The possibility that preferred modes of locomotion emerge from dynamical and optimality constraints and the energetic and dynamical constraints on preferred and predicted walking frequency are explored in this article. Participants were required to walk on a treadmill at their preferred frequency, at a frequency predicted as the resonance of a hybrid pendulum-spring model of the legs, and at frequencies ±15%, ±25%, ±35% of the predicted frequency. Walking at the preferred and predicted frequencies resulted in minimal metabolic costs and maximal stability of the head and joint actions. Mechanical energy conservation was constant across conditions. The head was more stable than the joints. The joints appeared to be in service of the head in maintaining a stable trajectory. The major findings of this study suggest a complementary relationship between energetic (physiological) and stability constraints in the adoption of a preferred frequency of walking. Multiple subsystems may be involved in constraining observed macroscopic behavior in intact biological systems. The approach and results of the study imply that a useful tack in understanding how dynamical control structures arise is to study the potential criteria that serve to act as constraints on skilled movement patterns in unimpaired and impaired populations.     

Vocal learning of a communicative signal in captive chimpanzees, Pan troglodytes

We hypothesized that chimpanzees could learn to produce attention-getting (AG) sounds via positive reinforcement. We conducted a vocal assessment in 76 captive chimpanzees for their use of AG sounds to acquire the attention of an otherwise inattentive human. Fourteen individuals that did not produce AG sounds during the vocal assessment were evaluated for their ability to acquire the use of an AG sound through operant conditioning and to employ these sounds in an attention-getting context. Nine of the 14 chimpanzees were successfully shaped using positive reinforcement to produce an AG sound. In a post-training vocal assessment, eight of the nine individuals that were successfully trained to produce AG sounds generalized the use of these newly acquired signals to communicatively relevant situations. Chimpanzees possess the ability to acquire the use of a communicative signal via operant conditioning and can generalize the use of this newly acquired signal to appropriate communicative contexts.     

Innovating With the Model of Human Occupation in Mental Health

This article describes a new approach in a group of National Health Service trusts in the United Kingdom. The assessment and intervention were focused on using the Model of Human Occupation in Mental Health services. An occupation focused assessment and intervention protocol were developed based on the Model of Human Occupation Screening Tool Single-Observation Form (MOHOST-SOF). The aim was to develop a guide to treatment and monitoring to support efficient practice while maintaining an occupation and client-centered focus. Implementation has been successful to date.     

Evolutionary Perspectives and Transdisciplinary Intersections: A Roadmap to Generative Areas of Overlap in Discussing Human Nature

This essay assesses a subset of approaches to the topic of human nature(s) and endeavors to identify generative areas of overlap for transdisciplinary conversation. Rather than pursue a resolution to the problem of potentially incompatible frameworks across perspectives, I seek to provide a template, or a roadmap, for a better conversation. My conclusions derive from a targeted literature assessment of subareas within the disciplines of philosophy, biology, anthropology, psychology, and theology, emphasizing those open to evolutionary contexts. I highlight eighteen core elements/themes and propose a few central thematic clusters as foci for moving the exchange on human nature between theology and science forward.     

Space Conquest and Ritual Practices: Lighting Candles for Ariane

Abstract

Endeavoring to conquer space—a domain once reserved to gods and spirits—is not always a denial of the existence of divinities and the human practices devoted to them. On the contrary, many examples of religious attitudes can be seen in the space venture of the past 50 years or so, such as lighting candles before launching a rocket or blessing a team of cosmonauts. To say that such behavior is an expression of the sacred dimension means recognizing that the space venture goes beyond the usual borders of human existence but, at the same time, does not reveal everything about mankind. There must always be a place for terrae incognitae—for unknown and uncharted lands.     

On genes,environments and human development: A commentary to Goossens

Using the example of adolescent loneliness, Goossens (this issue) presented an outline of integral research programmes in European developmental psychology. Integral research programmes should combine longitudinal analysis with state-of-the-art methods from the neurosciences and use the gene×environment approach to track differential susceptibility to the environment. In my commentary, I suggest using control variables in gene–environment studies to rule out spurious associations, to make the studies more developmentally sensitive, and to stress the need for replication of gene–environment findings. I offer two hypothetical models for developmentally sensitive gene–environment studies on adolescent loneliness, namely a social cognition model and a social rejection model.     

Factors underlying bus-related crashes in Hanoi,Vietnam

Road traffic crashes accounted for almost 13% of the total mortality recorded at the public health facilities in Vietnam in 2010. This qualitative study investigated factors related to bus-related crashes in Hanoi, Vietnam using focus group discussions and in-depth interviews among 75 participants who are bus drivers, motorcycle users, bus passengers, bus company managers, traffic policemen and local authorities. The results suggested that bus drivers were not the sole contributor to road traffic crashes with other vehicles. The rapid population growth due to rural to urban migration and the poor transport system appeared to be important contributing factors. In addition, “village culture” was likely to influence both the traffic behaviors of road users and the practices of law enforcement officers. Moreover, drink-driving behaviors appeared to be an important contributor to bus-related crashes. Supervision and penalty policies of bus companies also appeared to influence the driving performance of bus drivers. For a long-term solution to reduce bus-related crashes, it is vital to improve the transport infrastructure and the state management capacity regarding road safety as well as to assist the positive transition of citizens migrating from rural areas to their new urban lifestyle.