Cognitions, metacognitions, and chronic pain

Purpose: Although the content of thoughts has received a considerable amount of attention in pain research, the importance of thought processes (metacognitions) has received less attention. Method: One hundred twenty-nine individuals with muscular dystrophy and chronic pain completed measures assessing metacognitions and frequency of both catastrophizing and pain control beliefs. Results: Greater use of reappraisal and distraction metacognitions were associated with more perceived control over pain, whereas greater use of worry and punishment metacognitions were associated with more catastrophizing. Conclusions/Implications: The current findings indicate that metacognitions are associated with both pain control beliefs and catastrophizing and therefore may play an important role in the development or maintenance of pain-related cognitive content thought to influence patient functioning. Research is needed to determine whether treatments that encourage changes in both metacognitions and cognitive content are more effective than treatments that focus on cognitive content alone. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

Early changes in muscle activation patterns of toddlers during walking

Early locomotor behavior has been the focus of considerable attention by developmentalists over several decades. Few studies have addressed explicitly patterns of muscle activity that underlie this coordination pattern. Our purposes were to illustrate a method to determine objectively the onset and offset of muscle firings during early walking and to investigate the emergence of patterns of activation of the core locomotor muscles. We tested eight toddlers as they walked overground at walking onset (max. of 3-6 independent steps) and after three months of walking experience. Surface electrodes monitored activity of the gastrocnemius, tibialis anterior, quadriceps, and hamstrings. We reduced EMG signals to a frame-by-frame designation of "on-off," followed by muscle state and co-contraction analyses, and probability distributions for each muscle's activity across multiple cycles. Our results clearly show that at walking onset muscle activity was highly variable with few, if any, muscles showing recurring patterns of behavior, within or among toddlers. Variability and co-activation decreased with walking experience but remained inconsistent, in contrast to the significant increase in stability shown for joint coordination and endpoint (foot placement) parameters. We propose this trend emerges because of the high number of options (muscle combinations) available. Toddlers learn first to marshal sufficient force to balance and make forward progress but slowly discover how to optimize these resources.     

Measures of Mentoring,Department Climate,and Graduate Student Preparedness in the Responsible Conduct of Psychological Research

Drawing upon two independent national samples of 201 and 241 psychology graduate students, this article describes the development and psychometric evaluation of 4 Web-based student self-report scales tapping student socialization in the responsible conduct of research (RCR) with human participants. The Mentoring the Responsible Conduct of Research Scale (MRCR) is composed of 2 subscales assessing RCR instruction and modeling by research mentors. The 2 subscales of the RCR Department Climate Scale (RCR-DC) assess RCR department policies and faculty and student RCR practices. The RCR Preparedness scale (RCR-P) and the RCR Field Integrity scale (RCR-FI) measure respectively students' confidence in their ability to conduct research responsibly and their belief in the RCR integrity of psychology as a discipline. Factor analysis, coefficient alphas, correlations, and multiple regression analyses demonstrated each of the scales had good internal consistency and concurrent and construct validity.     

Characterization and sociocultural predictors of neuropsychological test performance in HIV+ Hispanic individuals

Hispanic individuals in the U.S. have been disproportionately impacted by HIV/AIDS, yet little is known regarding the neuropsychological sequelae of HIV within the Hispanic population. This study characterized neuropsychological (NP) test performance of HIV+ English-speaking Hispanic participants (n = 51) and investigated the combined roles of sociocultural factors (e.g., ethnicity, socioeconomic status [SES] proxy, and reading level) on NP test performance among our HIV+ Hispanic and non-Hispanic White participants (n = 49). Results revealed that the pattern of NP impairment in HIV+ Hispanic participants is consistent with the frontal-striatal pattern observed in HIV-associated CNS sequelae, and the overall prevalence of global NP impairment was high compared to previous reports with more ethnically homogeneous, non-Hispanic White cohorts. Multivariate prediction models that considered both sociocultural factors and CD4 count revealed that reading level was the only unique predictor of global NP functioning, learning, and attention/working memory. In contrast, ethnicity was the only unique predictor of abstraction/executive functioning. This study provides support for the use of neuropsychological evaluation in detecting HIV-associated NP impairment among HIV+ Hispanic participants and adds to the growing literature regarding the importance of considering sociocultural factors in the interpretation of NP test performance.     

Discovery of the pendulum and spring dynamics in the early stages of walking

The authors investigated the self-selected, overground walking patterns of 7 children (aged 11 months to 1 year, 5 months) at the initiation of walking (brand-new walkers [BNWs]) and for the next 6 months at 1-month intervals. Walking speed, stride length, and stride frequency increased significantly between the first 2 visits without significant changes in height and weight. The authors calculated sagittal plane angular accelerations of the center of mass over the foot for each step as an indicator of the escapement pulse. Results for the acceleration profiles changed after the 1st visit to positive, single-peaked accelerations that occurred < 0.20 s after initial foot contact. Increases in sagittal plane hip angular displacement and decreases in frontal plane pelvic angular displacement were observed. The pattern changes suggest that children quickly discover appropriately timed and directed escapements that initiate and support the conservative sagittal plane pendulum and spring dynamics observed in older children.     

How to crack nuts: acquisition process in captive chimpanzees (Pan troglodytes) observing a model

Stone tool use for nut cracking consists of placing a hard-shelled nut onto a stone anvil and then cracking the shell open by pounding it with a stone hammer to get to the kernel. We investigated the acquisition of tool use for nut cracking in a group of captive chimpanzees to clarify what kind of understanding of the tools and actions will lead to the acquisition of this type of tool use in the presence of a skilled model. A human experimenter trained a male chimpanzee until he mastered the use of a hammer and anvil stone to crack open macadamia nuts. He was then put in a nut-cracking situation together with his group mates, who were naïve to this tool use; we did not have a control group without a model. The results showed that the process of acquisition could be broken down into several steps, including recognition of applying pressure to the nut, emergence of the use of a combination of three objects, emergence of the hitting action, using a tool for hitting, and hitting the nut. The chimpanzees recognized these different components separately and practiced them one after another. They gradually united these factors in their behavior leading to their first success. Their behavior did not clearly improve immediately after observing successful nut cracking by a peer, but observation of a skilled group member seemed to have a gradual, long-term influence on the acquisition of nut cracking by naïve chimpanzees.     

A biomechanical analysis of the 'high guard' position of arms during walking in toddlers

In this study, we investigated biomechanical contributions of the high guard position of the arms observed only in a subgroup of toddlers at very early stages of gait development. Six healthy toddlers who showed this peculiar arm posture were involved in this study. They participated in two data collection sessions (1 month apart). We used three-dimensional analysis of arm posture during gait to estimate the changes in forces and torques generated by the arms and acting on the upper trunk segment. Across visits, toddlers’ increase in walking speeds coincided with lowering arm postures. Despite the apparent trend of changes in arm posture in this group of toddlers, the interaction between arm posture and upper trunk position created a variety of changes in forces and torques among individuals. Findings of this study exhibited an example of the exploration of dynamics by toddlers in the early stage of gait development.     

The effects of warned loss magnitude and timeout duration on human avoidance behavior

This study experimentally investigated the determinants of avoidance behavior when participants are forewarned of aversive outcomes. The effects of 3 variables on avoidance behavior were examined: point-loss amount (5 levels, from 20 to 100 points), duration of timeout from positive reinforcement (5 levels, 20 to 100 s), and 3 predictive accuracy levels (100%, 50%, and 0%) of warning stimuli. Twelve participants completed 3 sessions, each comprising 25 discrete trials, that differed in predictive accuracy level. Throughout a session, a participant engaged in button press responses that were reinforced by points under a conjunctive fixed-ratio fixed-interval schedule. During each trial, a warning stimulus that indicated a loss amount and a timeout duration was presented. If the participant pressed the avoidance button, then the timeout started, otherwise the loss occurred. The trial ended with termination of timeout or an occurrence of the loss. Results showed that avoidance responses increased when the loss amount increased and decreased when the timeout duration increased. The frequency of avoidance responses was lowest when the predictive accuracy of warning stimuli was 0%. These findings demonstrated that this experimental procedure could be useful for investigating human avoidance behavior outside the laboratory.     

Conserved evolutionary history for quick detection of threatening faces

Humans quickly recognize threats such as snakes and threatening faces, suggesting that human ancestors evolved specialized visual systems to detect biologically relevant threat stimuli. Although non-human primates also detect snakes quickly, it is unclear whether primates share the efficient visual systems to process the threatening faces of their conspecifics. Primates may not necessarily process conspecific threats by facial expressions, because threats from conspecifics in natural situations are often accompanied by other cues such as threatening actions (or attacks) and vocal calls. Here, we show a similar threat superiority effect in both humans and macaque Japanese monkeys. In visual search tasks, monkeys and humans both responded to pictures of a threatening face of an unfamiliar adult male monkey among neutral faces faster than to pictures of a neutral face among threatening faces. However, the monkeys’ response times to detect deviant pictures of a non-face stimulus were not slower when it was shown among threat faces than when it was shown among neutral faces. These results provide the first evidence that monkeys have an attentional bias toward the threatening faces of conspecifics and suggest that threatening faces are evolutionarily relevant fear stimuli. The subcortical visual systems in primates likely process not only snakes, but also more general biological threat-relevant stimuli, including threatening conspecific faces.