Negative hysteresis in the behavioral dynamics of the affordance “graspable”

One commonly perceives whether a visible object will afford grasping with one hand or with both hands. In experiments in which differently sized objects of a fixed type are presented, the transition from using one of these manual modes to the other depends on the ratio of object size to hand span and on the presentation sequence, with size increasing versus decreasing. Conventional positive hysteresis (i.e., a larger transition ratio for the increasing sequence) can be accommodated by the order parameter dynamics that typify self-organizing systems (Lopresti-Goodman, Turvey, and Frank, Attention, Perception, & Psychophysics 73:1948–1965, 2011). Here we identified and addressed conditions of unconventional negative hysteresis (i.e., a larger transition ratio for the decreasing sequence). They suggest a second control parameter in the self-organization of affordance perception, one that is seemingly regulated by inhibitory dynamics occurring in the agent–task–environment system. Our experimental results and modeling extend the investigation of affordance perception within dynamical systems theory.     

Levels of visuo-spatial selection: An ERP study of negative priming

Usually, a probe target appearing in a recently ignored distractor location is less efficiently processed. This robust phenomenon is called (visuo-) spatial negative priming (SNP). Among other explanations, concepts of persisting or retrieved spatial inhibition play a major role. Two relevant issues were investigated using event-related brain potentials (ERPs). The first pertains to context sensitivity of inhibition: Is a probe distractor necessary for SNP? The second concerns levels of processing at which spatial inhibition operates: Does SNP affect perception, selection, and/or stimulus classification? A localization task with and without probe distractors was employed while 64-channel EEG was recorded. Obviously, SNP does not require a probe distractor; the distractor-absent SNP effect was larger than the distractor-present SNP effect. Distractor-present SNP had two lateralized ERP effects, N1pc amplitude reduction and N2pc amplitude increase. Smaller N1pc may indeed reflect perceptual decrement, but was inversely related to size of behavioral SNP. By contrast, only strong-SNP participants showed N2pc increase, which points to selection disadvantage due to persisting inhibition of higher-level spatial representations. Distractor-absent SNP had no N1pc/N2pc correlates; instead, reduced amplitude of a broadly distributed P300 component suggests impaired stimulus classification due to episodic retrieval of inappropriate prime information. Overall, SNP seems to emerge from relatively late stages of processing, thus challenging the idea of context-free persisting inhibition of low-level spatial representations. Furthermore, distractor-present and distractor-absent SNP are qualitatively different from each other.     

Neurocognitive Sequelae of Pediatric Sickle Cell Disease: A Review of the Literature

This literature review summarizes all studies relating neuropsychological performance to neuroimaging findings in pediatric sickle cell disease (N=28; published 1991–2005). Although inconsistencies exist within and across domains, deficits in intelligence (IQ), attention and executive functions, memory, language, visuomotor abilities, and academic achievement have been identified. Overall neurocognitive compromise was revealed to be related to the level of neurological injury and the location of silent infarct. Attentional and executive dysfunction is prevalent and related to frontal lobe abnormalities.     

Children's Spatial Behavior is Differentially Affected After Traumatic Brain Injury

Spatial behavior in 20 children with severe traumatic brain injury (TBI) and 20 healthy controls was investigated using the Kiel Locomotor Maze. Children had to remember defined locations in an experimental chamber with completely controlled intra- and extra-maze cues until learning criterion was reached. In a second experiment, spatial orientation strategies were assessed. Children with TBI were shown to be impaired in spatial learning and spatial memory. Spatial orientation was found to be deficient even in cases where spatial learning and memory proved to be unimpaired, especially in tasks that demanded the use of relational place strategies. Children who suffered a TBI at an early age proved to be more severely impaired in spatial learning and orientation than older children.     

Economic Disadvantage and Young Children’s Emotional and Behavioral Problems: Mechanisms of Risk

This study aimed to establish potential mechanisms through which economic disadvantage contributes to the development of young children’s internalizing and externalizing problems. Prospective data from fetal life to age 3 years were collected in a total of 2,169 families participating in the Generation R Study. The observed physical home environment, the provision of learning materials in the home, maternal depressive symptoms, parenting stress, and harsh disciplining practices were all analyzed as potential mediators of the association between economic disadvantage and children’s internalizing and externalizing problem scores. Findings from structural equation modeling showed that for both internalizing and externalizing problems, the mechanisms underlying the effect of economic disadvantage included maternal depressive symptoms, along with parenting stress and harsh disciplining. For internalizing but not for externalizing problem scores, the lack of provision of learning materials in the home was an additional mechanism explaining the effect of economic disadvantage. The current results suggest that interventions that focus solely on raising income levels may not adequately address problems in the family processes that emerge as a result of economic disadvantage. Policies to improve the mental health of mothers with young children but also their home environments are needed to change the economic gradient in child behavior.     

A school-based assessment of secondary stressors and adolescent mental health 18 months post-Katrina

The goals of the current study were to examine the prevalence of secondary stressors related to Hurricane Katrina and to determine their impact on posttraumatic stress disorder (PTSD) symptoms among a sample of high school students. In addition, the moderating role of problem substance use was examined to determine whether it increased the risk of PTSD symptoms in the face of secondary stressors. A total of 271 ethnically and socioeconomically diverse adolescents completed an anonymous survey. Results indicated that problem substance use potentiated the positive relation between secondary stressors and PTSD symptoms, specifically symptoms of re-experiencing. The findings highlight the need for school-based assessment of and interventions for the long-term psychological effects of disasters.     

Polynomial Regression with Response Surface Analysis: A Powerful Approach for Examining Moderation and Overcoming Limitations of Difference Scores

Polynomial regression with response surface analysis is a sophisticated statistical approach that has become increasingly popular in multisource feedback research (e.g., self-observer rating discrepancy). The approach allows researchers to examine the extent to which combinations of two predictor variables relate to an outcome variable, particularly in the case when the discrepancy (difference) between the two predictor variables is a central consideration. We believe this approach has potential for application to a wide variety of research questions. To enhance interest and use of this technique, we provide ideas for future research directions that might benefit from the application of this analytic tool. We also walk through a step-by-step example of how to conduct polynomial regression and response surface analysis and provide all the tools you will need to do the analyses and graph the results (including SPSS syntax, formulas, and a downloadable Excel spreadsheet). Our example involves how discrepancies in perceived supervisor and organizational support relate to affective commitment. Finally, we discuss how this approach is a better, more informative alternative to difference scores and can be applied to the examination of two-way interactions in moderated regression.     

Evaluation of Techniques to Promote Generalization with Basic Math Fact Skills

The purpose of the current study was to investigate the effect of three procedures designed to promote the generalization of fluent responding of 12 addition facts to 12 related subtraction facts. The first procedure was completed to determine whether increases in the number of digits correct per minute computed on addition facts would generalize to related subtraction facts. If students were fluent in the targeted addition problems and no generalization was detected, a second procedure was implemented where students completed a conceptual lesson. If no generalization was observed during this phase, a third procedure was implemented where students completed addition problems presented in a cloze format. Results failed to demonstrate generalized fluency gains across any of the procedures. Discussion focuses on future directions of generalization research to further our understanding of the conditions needed for generalization to occur.     

Teacher Job Stress and Satisfaction in Urban Schools: Disentangling Individual-, Classroom-, and Organizational-Level Influences

Schools remain among the most frequent providers of children’s mental health services, particularly in low-income urban settings. Several decades of research have focused on training teachers to implement evidence-based interventions for minimizing disruptive behavior. Studies consistently demonstrate robust improvements in student behavior and learning; however, the impact on teachers’ work-related stress or satisfaction is not well understood. Six urban, high-poverty elementary schools were randomly assigned to a school mental health services model (Links to Learning; L2L) for referred, disruptive students or to services and professional development as usual (SAU). Teachers (n = 71, K-4 general education teachers) in L2L schools participated in professional development and consultation in two universal and two targeted interventions to reduce disruptive behaviors and promote learning. Teachers (n = 65) in SAU schools participated in professional development as usual. Multiple regression models examined teacher reports of individual-level self-efficacy, classroom-level student functioning, and school-level organizational health as predictors of stress and satisfaction. Findings revealed no significant difference between conditions on teacher work-related stress or satisfaction. Organizational health was the strongest predictor of stress and satisfaction. Training on and implementation of evidence-based classroom interventions did not appear to significantly impact teachers’ work-related stress or satisfaction. Instead, findings point to organizational climate and teacher connectedness as potential levers for change, supporting prior work on teacher stress and satisfaction in schools. The significance of targeting organizational factors may be particularly significant in urban school districts.     

Religion,Race, and Discrimination: A Field Experiment of How American Churches Welcome Newcomers

This article reports the results of a nationwide audit study testing how Christian churches welcome potential newcomers to their churches as a function of newcomers’ race and ethnicity. We sent email inquiries to 3,120 churches across the United States. The emails were ostensibly from someone moving to the area and looking for a new church to attend. That person's name was randomly varied to convey different racial and ethnic associations. In response to these inquiries, representatives from mainline Protestant churches—who generally embrace liberal, egalitarian attitudes toward race relations—actually demonstrated the most discriminatory behavior. They responded most frequently to emails with white‐sounding names, somewhat less frequently to black‐ or Hispanic‐sounding names, and much less to Asian‐sounding names. They also sent shorter, less welcoming responses to nonwhite names. In contrast, evangelical Protestant and Catholic churches showed little variation across treatment groups in their responses. These findings underscore the role of homophily, organizational homogeneity, and the costs of racial integration in perpetuating the racial segregation of American religious life.