The perception of minimal structures: performance on open and closed versions of visually presented Euclidean travelling salesperson problems

The planar Euclidean version of the travelling salesperson problem (TSP) requires finding a tour of minimal length through a two-dimensional set of nodes. Despite the computational intractability of the TSP, people can produce rapid, near-optimal solutions to visually presented versions of such problems. To explain this, MacGregor et al (1999, Perception 28 1417-1428) have suggested that people use a global-to-local process, based on a perceptual tendency to organise stimuli into convex figures. We review the evidence for this idea and propose an alternative, local-to-global hypothesis, based on the detection of least distances between the nodes in an array. We present the results of an experiment in which we examined the relationships between three objective measures and performance measures of optimality and response uncertainty in tasks requiring participants to construct a closed tour or an open path. The data are not well accounted for by a process based on the convex hull. In contrast, results are generally consistent with a locally focused process based initially on the detection of nearest-neighbour clusters. Individual differences are interpreted in terms of a hierarchical process of constructing solutions, and the findings are related to a more general analysis of the role of nearest neighbours in the perception of structure and motion.     

Influence of the teacher-student relationship on childhood conduct problems: a prospective study.

Examined the influence of the quality of the teacher-student relationship on children's subsequent levels of aggression in a sample of 61 second and third-grade children nominated and rated by their teachers as aggressive. The stability of teachers' and children's reports of relationships quality across academic years was in the low to moderate range. Teachers and children showed little agreement in their reports of relationship quality. Teachers' and children's reports of relationship quality in year 1 (Y1) predicted teacher-rated aggression the following year, controlling for Y1 ratings of aggression. Teachers' reports of relationship quality across Y1 and Y2 predicted peer-rated aggression, but not teacher-rated aggression, in Y3, controlling for Y1 aggression. Consistent with a buffering role for teacher-student relationships, a positive teacher-student relationship was of greatest benefit to children whose mothers reported rejecting parenting histories. We discuss implications for school-based prevention programs.     

United we stand, divided we fall: the education and training needs of clinical child psychologists

Reviews efforts to delineate training needs for psychologists who are providing clinical services to children, adolescents, and families. In particular, this article (a) describes efforts of clinical child and other psychologists who work with children, adolescents, and families to develop education and training guidelines; (b) discusses the overlap among various child and adolescent providers within psychology; and (c) highlights several key competencies that have been identified as important for all psychologists in practice roles with children and adolescents. In particular, we emphasize the need for greater collaboration and integration among various psychological specialties that focus on children, adolescents, and families and for greater system-wide discussion of training needs and priorities.     

On the nature of international sales and sales management research: a social network–analytic perspective

This research uses a combination of text mining, co-word analysis, and social network analysis (SNA) to review 132 international sales and sales management (ISSM) articles published between 1980 and 2017. The study provides a unique view of the past and future of ISSM research and provides three principal contributions. First, from a social network–analytic perspective, it offers a unique examination of the ways ISSM research topics are interconnected, as reflected by keyword network structure. Second, by conducting SNA across two periods (1980–1999 and 2000–2017) and examining the changes in network centrality measures, the study offers initial insights into the evolving nature of the ISSM literature. Third, the study reports keyword network disconnections (i.e., structural holes) to propose a fruitful agenda for future ISSM research. Taken together, this research offers a current perspective of the ISSM research domain's evolving nature.     

Modal preferences in creative problem solving

Embodied cognitive science appeals to the idea that cognition depends on the body as well as on the brain. This study looks at whether we are more likely to engage just the brain or enlist the body for complex cognitive functioning such as creative problem solving. Participants were presented with a puzzle based on De Bono's lateral thinking puzzles. The puzzle consisted of rotating and joining two-dimensional shapes to make a three-dimensional one. In one condition, participants were given the choice of either solving the puzzle mentally or through manipulation of the images on a computer screen. In another condition, the subjects had to solve the puzzle first mentally and then report which mode they would have preferred to solve the puzzle. Two more conditions were applied with slight variations. In all conditions, an overwhelming majority of participants chose to solve the puzzle by manipulation, even though there was not a significant increase on performance. It appeared that participants were making a conscious choice for the body to play a feedback-driven role in creative cognitive processing. This strong preference for manual manipulation over just mental representation, regardless of the impact on performance, would seem to suggest that it is our natural tendency to involve the body in complex cognitive functioning. This would support the theory that cognition may be more than just a neural process, and that it is a dynamic interplay between body, brain and world. The experiential feedback of the body moving through space and time may be an inherently important factor in creative cognition.     

Enhanced recognition and recall of new words in 7- and 12-year-olds following a period of offline consolidation

Recent studies of adults have found evidence for consolidation effects in the acquisition of novel words, but little is known about whether such effects are found developmentally. In two experiments, we familiarized children with novel nonwords (e.g., biscal) and tested their recognition and recall of these items. In Experiment 1, 7-year-olds were then retested on either the same day or the following day to examine changes in performance after a short delay compared with a longer delay that included sleep. Experiment 2 used two age groups (7- and 12-year-olds), with all participants being retested 24h later. The 12-year-olds accurately recognized the novel nonwords immediately after exposure, as did the 7-year-olds in Experiment 2 (but not in Experiment 1), suggesting generally good initial rates of learning. Experiment 1 revealed improved recognition of the novel nonwords after both short (3- to 4-h) and longer (24-h) delays. In contrast, recall was initially poor but showed improvements only when children were retested 24h later, not after a 3- to 4-h delay. Similar improvements were observed in both age groups despite better overall performance in 12-year-olds. We argue that children, like adults, exhibit offline consolidation effects on the formation of novel phonological representations.     

Learning new meanings for old words: effects of semantic relatedness

Changes to our everyday activities mean that adult language users need to learn new meanings for previously unambiguous words. For example, we need to learn that a "tweet" is not only the sound a bird makes, but also a short message on a social networking site. In these experiments, adult participants learned new fictional meanings for words with a single dominant meaning (e.g., "ant") by reading paragraphs that described these novel meanings. Explicit recall of these meanings was significantly better when there was a strong semantic relationship between the novel meaning and the existing meaning. This relatedness effect emerged after relatively brief exposure to the meanings (Experiment 1), but it persisted when training was extended across 7?days (Experiment 2) and when semantically demanding tasks were used during this extended training (Experiment 3). A lexical decision task was used to assess the impact of learning on online recognition. In Experiment 3, participants responded more quickly to words whose new meaning was semantically related than to those with an unrelated meaning. This result is consistent with earlier studies showing an effect of meaning relatedness on lexical decision, and it indicates that these newly acquired meanings become integrated with participants' preexisting knowledge about the meanings of words.     

Perceived Stress and Comorbid Illness Predict Depressive Symptomatology in People with Coeliac Disease

A high prevalence of depression is found in people with coeliac disease (CD). People with CD who are depressed are less likely to manage their illness effectively, which may lead to complications. Identification of variables associated with depression in people with CD may facilitate early detection and intervention. Participants were 749 members (125 males, 622 females) of the Queensland Coeliac Society (aged 18–88 years), recruited via a mailout. Participants completed the Modified Zung Self‐Rating Depression Scale, the Perceived Stress Scale, and the Perceived Consequences Subscale (from the Revised Illness Perception Questionnaire). Stress (p = .001) and comorbid medical illness (p = .01) were significantly associated with depression in CD. The current study made an original contribution to the body of literature by identifying stress and comorbid medical illness as predictors of depression in CD.