Eye movements during transitive action observation have sequential structure

In this paper, we explore how observers of a reach-to-grasp action can identify and distinguish between the agent and patient (i.e. target) of the action. We investigate the hypothesis that there is a characteristic sequential structure to the observer’s pattern of saccades, with the agent being fixated first, and then the target. We report an experiment which indicates that this sequence of saccades, while not ubiquitous, is overwhelmingly more likely than chance. The experiment also sheds some light on the mechanisms which allow the observer to saccade from the agent of the action to the target.     

Distribution-free tests of stochastic dominance for small samples

One variable is said to “stochastically dominate” another if the probability of observations smaller than x is greater for one variable than the other, for all x. Inferring stochastic dominance from data samples is important for many applications of econometrics and experimental psychology, but little is known about the performance of existing inferential methods. Through simulation, we show that three of the most widely used inferential methods are inadequate for use in small samples of the size commonly encountered in many applications (up to 400 observations from each distribution). We develop two new inferential methods that perform very well in a limited, but practically important, case where the two variables are guaranteed not to be equal in distribution. We also show that extensions of these new methods, and an improved version of an existing method, perform quite well in the original, unlimited case.     

State mood,task performance,and behavior at work: A within-persons approach

We examine the intra-individual relationships between state mood and the primary components of the individual-level criterion space (task performance, organizational citizenship behavior, and work withdrawal) as they vary within the stream of work. Using experience-sampling methods, 67 individuals in a call center responded to surveys on palmtop computers at random intervals 4–5 times each day for 3 weeks (total N = 2329). These data were matched to objective task performance obtained from organizational call records (total N = 1191). Within-persons, periods of positive mood were associated with periods of improved task performance (as evidenced by shorter call time) and engaging in work withdrawal. Trait meta-mood moderated these relationships. Specifically, individuals who attended to their moods had a stronger relationship between mood and speed of task performance (call time) and individuals able to repair their mood cognitively evidenced a weaker relationship between mood and withdrawal. Implications and the use of within-persons designs are discussed.     

The effects of post-encoding stress on recognition memory: examining the impact of skydiving in young men and women

Prior studies have indicated that post-encoding stress can protect memories from the effects of forgetting, and this has been taken as evidence that stress facilitates memory consolidation. However, it is not known whether stress acts by directly influencing the strength of the underlying memories or whether it influences the generation process that plays a critical role in tests such as free recall. To address this issue, we examined the effects of stress produced by skydiving on recognition memory for negative and neutral pictures. Relative to a non-stress control condition, post-encoding stress in males was found to increase recognition memory for neutral pictures. However, stress was not found to improve recognition for emotional pictures, nor was it found to influence recognition memory in female participants. Additional analysis of recognition performance suggested that stress increased familiarity-based recognition rather than recollection. This study indicates that stress can improve familiarity-based recognition, thus showing that stress directly increases the strength of the underlying memories.     

Modulation of N400 in chronic non-fluent aphasia using low frequency Repetitive Transcranial Magnetic Stimulation (rTMS)

Low frequency Repetitive Transcranial Magnetic Stimulation (rTMS) has previously been applied to language homologues in non-fluent populations of persons with aphasia yielding significant improvements in behavioral language function up to 43 months post stimulation. The present study aimed to investigate the electrophysiological correlates associated with the application of rTMS through measurement of the semantic based N400 Event-related brain potentials (ERP) component. Low frequency (1 Hz) rTMS was applied to the anterior portion of the homologue to Broca’s area (pars triangularis), for 20 min per day for 10 days, using a stereotactic neuronavigational system. Twelve non-fluent persons with aphasia, 2-6 years post stroke were stimulated. Six participants were randomly assigned to receive real stimulation and six participants were randomly assigned to receive a blind sham control condition. ERP measures were recorded at baseline, 1 week and 2 months subsequent to stimulation. The findings demonstrate treatment related changes observed in the stimulation group when compared to the placebo control group at 2 months post stimulation indicating neuromodulation of N400 as a result of rTMS. No treatment related changes were identified in the stimulation group, when compared to the sham group from baseline to 1 week post stimulation. The electrophysiological results represent the capacity of rTMS to modulate neural language networks and measures of lexical-semantic function in participants with non-fluent aphasia and suggest that time may be an important factor in brain reorganization subsequent to rTMS.     

Word recognition across orthographies: Another look at the interaction between context and degradation

Abstract

The performance of English and Spanish subjects was examined in two experiments using a lexical decision task in which the effects of semantic priming and stimulus degradation were systematically varied. The Orthographic Depth Hypothesis predicts that priming and degradation will interact in the orthographically “deep” language (English) but not in the “shallow” one (Spanish). In the first experiment, the two factors were found to interact in a similar way in both English and Spanish groups. In the second experiment, in which only Spanish subjects participated, the interaction was again present but only in those subjects who showed an overall facilitation effect on primed words. The results are consistent with the use of the so-called “direct” route in Spanish and are at variance with other previous findings which have suggested that reading in shallow orthographies occurs via the “indirect” phonological route. There was also evidence that nonword rejection times were slower in Spanish subjects and that the performance of the two groups was affected differently by the different types of neutral baseline primes (asterisks or unrelated words). Possible interpretations of these performance variations are briefly discussed.     

Applied Research and Zoo Education: The Evolution and Evaluation of a Public Talks Program using Unobtrusive Video Recording of Visitor Behavior

ABSTRACT

The provision of high-quality conservation education has become a priority for modern zoos. This can be delivered in a number of differing ways to account for differences in learning styles and prior knowledge of zoo visitors. At Chester Zoo (United Kingdom), a team of full-time and highly trained interpreters (known as presenters) deliver a diverse public talks program every day of the year. Although these talks attract a large audience, little was understood about their impact on the visitor. As a result, an extensive, unobtrusive study using video recording equipment was undertaken to assess visitor behavior. Results suggest that visitor attentiveness was much higher among those individuals who found themselves in a better viewing position (where they could see the animal and presenter). Visitors who were in poor-visibility positions showed less attention than visitors who were observed under control conditions, without an accompanying talk, indicating a high environmental component to learning potential. When interactive elements were included in a talk (such as an animal feed or enrichment activity) attentiveness was dramatically increased. More crucially, however, was that during talks where there was no interactivity or animals were inactive, attentiveness fell to below control levels, suggesting that heightened visitor expectations created by the anticipation for the talk were not being met—a serious barrier to learning. These findings offer a series of measures that can be taken to improve the educational impact of a zoo talks program whilst, at the same time, providing a better quality experience for zoo visitors.     

Competing perspectives on deviance

This paper presents an assessment of the theoretical conflicts and debates within the sociology of deviance over the past two decades. It delineates the epistemological and theoretical confusion that currently characterize the field, and points out some of the dangers that this factionalization entails.     

Immediate Movement History Influences Reach-to-Grasp Action Selection in Children and Adults

The authors review studies of mentally simulated movements. In automatic or cyclical movements, actual and motor imagery (MI) durations are similar. When athletes simulate only dynamic phases of movement or perform MI just before competing, however, environmental and time constraints lead to an underestimation of actual duration. Conversely, complex attention-demanding movements take longer to image. Finally, participants can modify the speed of MI voluntarily when they receive specific instructions. To complete the available data, the authors compared imagined and actual durations in tennis and gymnastics. Results showed systematic and disproportionate overestimation of actual duration. The authors found a relationship between complex motor skills and MI duration. They discuss the factors leading to over- and underestimation and the hypotheses that could be tested.