Does stress run through the leash? An examination of stress transmission between owners and dogs during a walk

Animal Cognition - Humans and dogs have co-evolved for over 10,000 years. Recent research suggests that, through the domestication process, dogs have become proficient at responding to...     

Are Episodic Buffer Processes Intact in ADHD? Experimental Evidence and Linkage with Hyperactive Behavior

Working memory deficits are present in a substantial proportion of children with ADHD, and converging evidence links these deficits with ADHD-related behavioral and functional impairments. At the same time, working memory is not a unitary construct, and evidence is lacking regarding the role of several components of this system in ADHD. Preclinical behavioral studies are needed to fractionate the multicomponent working memory system, determine which specific subcomponent(s) are impaired in ADHD, and more importantly link these subcomponent(s) with specific ADHD-related behavioral symptoms/functional impairments. The current study reflects one piece of that puzzle, and focuses on the episodic buffer component of working memory. Across multiple testing days, a well-characterized sample of 86 children ages 8–13 (M=10.52, SD=1.54; 34 girls; 64% Caucasian/Non-Hispanic) with ADHD (n=49) and without ADHD (n=37) completed three counterbalanced working memory tests that were identical in all aspects except the key subcomponent process (phonological, visuospatial, episodic buffer). Gross motor movement during these and control tasks were measured using 4 high-precision actigraphs. There was no evidence of group differences in gender, age, SES, or IQ. Bayesian mixed-model ANOVAs indicated that the ADHD group performed significantly worse on all three working memory tests (d=1.17–1.44) and was significantly more hyperactive than controls (d=0.66–1.05) during the visuospatial and episodic buffer tests. In contrast, the ADHD and Non-ADHD groups were equivalent with regard to effects of episodic buffer demands on performance and hyperactive behavior. The most parsimonious conclusion is that the episodic buffer is likely intact in ADHD, and unrelated to ADHD hyperactivity symptoms.     

Predictors of physical activity,healthy eating and being smoke-free in teens: A theory of planned behaviour approach

This paper elicited context specific underlying beliefs for physical activity, fruit and vegetable consumption and smoke-free behaviour from the Theory of Planned Behaviour (TPB), and then determined whether the TPB explained significant variation in intentions and behaviour over a 1 month period in a sample of grade 7–9 (age 12–16 years) adolescents. Eighteen individual interviews and one focus group were used to elicit student beliefs. Analyses of this data produced behavioural, normative and control beliefs which were put into a TPB questionnaire completed by 183 students at time 1 and time 2. The Path analyses from the main study showed that the attitude/intention relationship was moderately large for fruit and vegetable consumption and small to moderate for being smoke free. Perceived behavioural control had a large effect on being smoke free and a moderately large effect for fruit and vegetable consumption and physical activity. Intention had a large direct effect on all three behaviours. Common (e.g. feel better, more energy) and behaviour-specific (e.g., prevent yellow fingers, control my weight) beliefs emerged across the three health behaviours. These novel findings, to the adolescent population, support the importance of specific attention being given to each of the behaviours in future multi-behavioural interventions.     

Dimensions of perceived control: A factor analysis of three measures and an examination of their relation to activity level and mood in a student and cross-cultural patient sample

Abstract

This study investigated whether measures of three perceived control (PC) concepts tapped independent dimensions, were invariant to population characteristics of health and culture, were differentially sensitive to health outcomes, and were discriminable from self-report disability. The Multidimensional Health Locus of Control, Generalized Self-efficacy, and Perceived Health Competence (PHC) Scales were administered to 106 Scottish students and 145 Scottish, Spanish and Irish patients, who also completed versions of the Sickness Impact Profile. Principal Components analyses revealed five factors reflecting scale constructions for students and six factors for patients, as PHC items fell on two factors. Disability items fell on a separate factor from all PC items. Results suggest: (a) PC is multidimensional regardless of health and culture; (b) adequate assessment requires multiple PC measures; and (c) it is meaningful to consider PC as a possible influence on disability.     

Abstracting Sequences: Reasoning That Is a Key to Academic Achievement

The ability to understand sequences of items may be an important cognitive ability. To test this proposition, 8 first-grade children from each of 36 classes were randomly assigned to four conditions. Some were taught sequences that represented increasing or decreasing values, or were symmetrical, or were rotations of an object through 6 or 8 positions. Control children received equal numbers of sessions on mathematics, reading, or social studies. Instruction was conducted three times weekly in 15-min sessions for seven months. In May, the children taught sequences applied their understanding to novel sequences, and scored as well or better on three standardized reading tests as the control children. They outscored all children on tests of mathematics concepts, and scored better than control children on some mathematics scales. These findings indicate that developing an understanding of sequences is a form of abstraction, probably involving fluid reasoning, that provides a foundation for academic achievement in early education.     

Body shape and size depictions of African American women in JET magazine, 1953-2006

Depictions of Caucasian women in the mainstream media have become increasingly thinner in size and straighter in shape. These changes may be inconsistent with the growing influence of African American beauty ideals, which research has established as more accepting of larger body sizes and more curvaceous body types than Caucasians. The present study looked at trends in the portrayal of African American women featured in JET magazine from 1953 to 2006. Beauty of the Week (BOW) images were collected and analyzed to examine body size (estimated by independent judges) and body shape (estimated by waist-to-hip ratio). We expected body sizes to increase and body shapes to become more curvaceous. Results revealed a rise in models' body size consistent with expectations, but an increase in waist-to-hip ratio, contrary to prediction. Our findings suggest that the African American feminine beauty ideal reflects both consistencies with and departures from mainstream cultural ideals.     

Development of big five domains and facets in adulthood: mean-level age trends and broadly versus narrowly acting mechanisms

Data from a cross‐sectional sample (N = 601 men and women) and a longitudinal sample (N = 125 women) were used to test hypotheses about the development of Big Five domains and facets from early adulthood through middle age. Analyses of mean‐level age trends indicated that overall Agreeableness and Conscientiousness increased with age and that several facets showed distinctive trends that replicated across the samples. Cross‐sectional analyses of trait intercorrelations and covariances indicated that interrelations between the Big Five domains, and between their more specific facets, were quite similar at older versus younger ages. Finally, longitudinal analyses of individual‐level changes indicated that (a) different people's personalities changed in markedly different ways; (b) these changes were predominantly independent, rather than correlated, across Big Five domains; and (c) the pattern of change correlations between Big Five facets could be explained by the facets’ interrelations at the first assessment time. Taken together, these results suggest that a complete understanding of personality development requires consideration of facet‐level traits and that adult personality development is predominantly influenced by narrowly acting mechanisms that each affect a single Big Five domain, or a small cluster of related facets, rather than by broadly acting mechanisms that simultaneously affect previously independent traits.     

Discrimination of geometric angles by adult humans

Men and women learned to discriminate between two different size angles presented to them as objects within a real-world task. During Experiment 1, participants in group 50 were trained to choose a 50° angle and participants in group 75 were trained to choose a 75° angle. During testing, both groups were provided with a choice between their training angle and one of a set of test angles that was either smaller or larger than the training angle. Results showed a generalized pattern of responding, with group 50 showing increased responding to test angles smaller than 50° and group 75 showing increased responding to test angles larger than 75°. Further analysis of the response patterns revealed that participants in group 50 showed evidence of absolute learning, whereas participants in group 75 showed evidence of relational learning. During Experiment 2, a third group of participants (group 25) trained to choose a smaller angle (25°) was included in addition to group 50 and group 75. Participants were trained with three angles present and tested with just two, one being their training angle and the other being one of a set of novel test angles. Similar to the participants from Experiment 1, group 75 showed evidence of relational learning. Group 50, for which no relational rule could be applied during training, showed an absolute learning pattern with no response shift to test angles smaller or larger than their training angle. Group 25 showed evidence of absolute responding that was more pronounced than that found for the smallest training angle during Experiment 1. These findings suggest differential learning of geometric angles based on amplitude with smaller angles perceived as more distinct and thus more resistant to broader generalization than larger angles. Implications of these results are that certain geometric properties may be subject to different learning processes based on the specific magnitude of that property.     

Let the pigeon drive the bus: pigeons can plan future routes in a room

The task of determining an optimal route to several locations is called the traveling salesperson problem (TSP). The TSP has been used recently to examine spatial cognition in humans and non-human animals. It remains unclear whether or not the decision process of animals other than non-human primates utilizes rigid rule-based heuristics, or whether non-human animals are able to flexibly ‘plan’ future routes/behavior based on their knowledge of multiple locations. We presented pigeons in a One-way and Round-Trip group with TSPs that included two or three destinations (feeders) in a laboratory environment. The pigeons departed a start location, traveled to each feeder once before returning to a final destination. Pigeons weighed the proximity of the next location heavily, but appeared to plan ahead multiple steps when the travel costs for inefficient behavior appeared to increase. The results provide clear and strong evidence that animals other than primates are capable of planning sophisticated travel routes.