Developmental differences in the control of action selection by social information

Our everyday actions are often performed in the context of a social interaction. We previously showed that, in adults, selecting an action on the basis of either social or symbolic cues was associated with activations in the fronto-parietal cognitive control network, whereas the presence and use of social versus symbolic cues was in addition associated with activations in the temporal and medial prefrontal cortex (MPFC) social brain network. Here we investigated developmental changes in these two networks. Fourteen adults (21–30 years of age) and 14 adolescents (11–16 years) followed instructions to move objects in a set of shelves. Interpretation of the instructions was conditional on the point of view of a visible “director” or the meaning of a symbolic cue (Director Present vs. Director Absent) and the number of potential referent objects in the shelves (3-object vs. 1-object). 3-object trials elicited increased fronto-parietal and temporal activations, with greater left lateral prefrontal cortex and parietal activations in adults than adolescents. Social versus symbolic information led to activations in superior dorsal MPFC, precuneus, and along the superior/middle temporal sulci. Both dorsal MPFC and left temporal clusters exhibited a Director × Object interaction, with greater activation when participants needed to consider the directors' viewpoints. This effect differed with age in dorsal MPFC. Adolescents showed greater activation whenever social information was present, whereas adults showed greater activation only when the directors' viewpoints were relevant to task performance. This study thus shows developmental differences in domain-general and domain-specific PFC activations associated with action selection in a social interaction context

Children’s Gender Development: Sibling Configuration and Maternal Influence

We present a study of 3- to 8-year-old children in various family types. Family type influenced some outcomes, although many measures were unrelated to family type. Additionally, some relationships between maternal attitudes about gender-related behavior differed between boys and girls, and in different family configurations

Unaffected perceptual thresholds for biological and non-biological form-from-motion perception in autism spectrum conditions

Background: Perception of biological motion is linked to the action perception system in the human brain, abnormalities within which have been suggested to underlie impairments in social domains observed in autism spectrum conditions (ASC). However, the literature on biological motion perception in ASC is heterogeneous and it is unclear whether deficits are specific to biological motion, or might generalize to form-from-motion perception. Methodology and Principal Findings: We compared psychophysical thresholds for both biological and non-biological form-from-motion perception in adults with ASC and controls. Participants viewed point-light displays depicting a walking person (Biological Motion), a translating rectangle (Structured Object) or a translating unfamiliar shape (Unstructured Object). The figures were embedded in noise dots that moved similarly and the task was to determine direction of movement. The number of noise dots varied on each trial and perceptual thresholds were estimated adaptively. We found no evidence for an impairment in biological or non-biological object motion perception in individuals with ASC. Perceptual thresholds in the three conditions were almost identical between the ASC and control groups. Discussion and Conclusions: Impairments in biological motion and non-biological form-from-motion perception are not across the board in ASC, and are only found for some stimuli and tasks. We discuss our results in relation to other findings in the literature, the heterogeneity of which likely relates to the different tasks performed. It appears that individuals with ASC are unaffected in perceptual processing of form-from-motion, but may exhibit impairments in higher order judgments such as emotion processing. It is important to identify more specifically which processes of motion perception are impacted in ASC before a link can be made between perceptual deficits and the higher-level features of the disorder

The relationship between pubertal status and neural activity during risky decision-making in male adolescents

- Purpose: Adolescence is a time of dramatic changes in a range of behaviours, which occur in tandem with changes in brain structure and function. These coincide with the physiological changes of puberty, but little research has focussed on the possible contributing role of puberty. One important behaviour emerging in adolescence is the increased propensity to make risky decisions. A prominent theory to explain this increased propensity for risk is the ‘dual systems’ model (Casey et al., 2008), where risky decisions result from a dissociation in the timing of the maturation of the limbic system and the prefrontal cortex, both regions involved in risky decision-making. The limbic system (incorporating the ventral striatum) is hypothesised to mature relatively early in adolescence, and is thought to be related to pubertal maturation. In contrast, the prefrontal cortex is thought to undergo more protracted development throughout adolescence. This study explores how developmental changes in brain function when performing a risk-taking fMRI (functional Magnetic Resonance Imaging) task are related to puberty, independently of chronological age. - Methods: Forty-five male participants aged 13-14 years underwent fMRI scanning whilst performing a risk-taking task (BART task, adapted from Lejuez et al., 2002). In this age range, there is normal variability in pubertal development, with individuals being at all stages of puberty from pre-puberty to having completed puberty. In the BART task, participants had to decide whether to inflate a virtual balloon on a screen. Successful inflation of the balloon resulted in the opportunity to earn more money, but risked the balloon popping and the money being lost. Stopping allowed the participants to save the money towards their final earnings. Participants completed four six-minute runs of the task. Pubertal stage was assessed using self-report measures including a pictorial Tanner stage and the Pubertal Developmental Scale (Petersen et al., 1988). Salivary hormone levels were collected to measure levels of Testosterone, Oestradiol and DHEA. Participants also completed validated self-report questionnaires of risk-taking, impulsivity and sensation-seeking. - Results: The analysis focused on a main effect, across the entire group, of active decision-making compared to the control condition in regions including the prefrontal cortex and limbic system, which are known to be involved in risky decision-making. We also investigated whether this activation was differentially related to puberty across regions, using both group-wise and regression analyses. - Conclusions; This study investigated a role for puberty in the functional development of brain regions involved in risky decision-making in males, and further informs the usefulness of the dual systems model of risk taking during adolescence

Magnetic irreversibility and Verwey transition in nano-crystalline bacterial magnetite

The magnetic properties of biologically-produced magnetite nanocrystals biomineralized by four different magnetotactic bacteria were compared to those of synthetic magnetite nanocrystals and large, high quality single crystals. The magnetic feature at the Verwey temperature, $T_{V}$, was clearly seen in all nanocrystals, although its sharpness depended on the shape of individual nanoparticles and whether or not the particles were arranged in magnetosome chains. The transition was broader in the individual superparamagnetic nanoparticles for which $T_{B}<T_{V}$, where $T_{B}$ is the superparamagnetic blocking temperature. For the nanocrystals organized in chains, the effective blocking temperature $T_{B}>T_{V}$ and the Verwey transition is sharply defined. No correlation between the particle size and $T_{V}$ was found. Furthermore, measurements of $M(H,T,time)$ suggest that magnetosome chains behave as long magnetic dipoles where the local magnetic field is directed along the chain and this result confirms that time-logarithmic magnetic relaxation is due to the collective (dipolar) nature of the barrier for magnetic moment reorientation

Complex interventions reduce use of urgent healthcare in adults with asthma: systematic review with meta-regression.

Open access article.INTRODUCTION: Asthma accounts for considerable healthcare expenditure, a large proportion of which is attributable to use of expensive urgent healthcare. This review examines the characteristics of complex interventions that reduce urgent healthcare use in adults with asthma. METHOD: Electronic searches of MEDLINE, EMBASE, PSYCINFO, CINAHL, the British Nursing Library and the Cochrane library, from inception to January 2013 were conducted. Studies were eligible for inclusion if they: i) included adults with asthma ii) assessed the efficacy of a complex intervention using randomised controlled trial design, and iii) included a measure of urgent healthcare utilisation at follow-up. Data on participants recruited, methods, characteristics of complex interventions and the effects of the intervention on urgent healthcare use were extracted. RESULTS: 33 independent studies were identified resulting in 39 comparisons altogether. Pooled effects indicated that interventions were associated with a reduction in urgent healthcare use (OR = 0.79, 95% CI = 0.67, 0.94). When study effects were grouped according to the components of the interventions used, significant effects were seen for interventions that included general education (OR = 0.77, 95% CI = 0.64, 0.91), skills training (OR = 0.64, 95% CI = 0.48, 0.86) and relapse prevention (OR = 0.75, 95% CI = 0.57, 0.98). In multivariate meta-regression analysis, only skills training remained significant. CONCLUSIONS: Complex interventions reduced the use of urgent healthcare in adults with asthma by 21%. Those complex interventions including skills training, education and relapse prevention may be particularly effective in reducing the use of urgent healthcare in adults with asthma.National Institute for Health Research (NIHR

Puberty and risky decision-making in male adolescents

Pubertal development is a potential trigger for increases in risk-taking behaviours during adolescence. Here, we sought to investigate the relationship between puberty and neural activation during risky decision-making in males using functional magnetic resonance imaging (fMRI). Forty-seven males aged 12.5-14.5 years completed an fMRI risk-taking task (BART) and reported their tendencies for risky decision-making using a self-report questionnaire. Puberty was assessed through self-reported pubertal status and salivary testosterone levels. Testosterone concentration, but not physical pubertal status, was positively correlated with self-reported risk-taking behaviour, while neither was correlated with BART performance. Across the whole sample, participants had greater activation of the bilateral nucleus accumbens and right caudate on trials when they made a successful risky decision compared to trials when they made a safe choice or when their risky decision was unsuccessful. There was a negative correlation between pubertal stage and brain activation during unsuccessful risky decision-making trials compared within unsuccessful control trials. Males at a lower stage of pubertal development showed increased activation in the left insula, right cingulate cortex, dorsomedial prefrontal cortex (dmPFC), right putamen and right orbitofrontal cortex (OFC) relative to more pubertally mature males during trials when they chose to take a risk and the balloon popped compared to when they watched the computer make an unsuccessful risky decision. Less pubertally mature males also showed greater activation in brain regions including the dmPFC, right temporal and frontal cortices, right OFC, right hippocampus and occipital cortex in unsuccessful risky trials compared to successful risky trials. These results suggest a puberty-related shift in neural activation within key brain regions when processing outcomes of risky decisions, which may reduce their sensitivity to negative feedback, and in turn contribute to increases in adolescent risk-taking behaviours

Does anxiety predict the use of urgent care by people with long term conditions? A systematic review with meta-analysis

Objective: The role of anxiety in the use of urgent care in people with long term conditions is not fully understood. A systematic review was conducted with meta-analysis to examine the relationship between anxiety and future use of urgent healthcare among individuals with one of four long term conditions: diabetes; coronary heart disease, chronic obstructive pulmonary disease and asthma. Methods: Electronic searches of MEDLINE, EMBASE, PSYCINFO, CINAHL, the British Nursing Library and the Cochrane Library were conducted These searches were supplemented by hand-searching bibliographies, citation tracing eligible studies and asking experts within the field about relevant studies. Studies were eligible for inclusion if they: a) used a standardised measure of anxiety, b) used prospective cohort design, c) included adult patients diagnosed with coronary heart disease (CHD), asthma, diabetes or chronic obstructive pulmonary disease (COPD), d) assessed urgent healthcare use prospectively. Data regarding participants, methodology, and association between anxiety and urgent care use was extracted from studies eligible for inclusion. Odds ratios were calculated for each study and pooled using random effects models. Results: 8 independent studies were identified for inclusion in the meta-analysis, with a total of 28,823 individual patients. Pooled effects indicate that anxiety is not associated with an increase in the use of urgent care (OR. =. 1.078, p. =. 0.476), regardless of the type of service, or type of medical condition. Conclusions: Anxiety is not associated with increased use of urgent care. This finding is in contrast to similar studies which have investigated the role of depression as a risk factor for use of urgent care.This paper summarises independent research funded by the National Institute for Health Research (NIHR) under its Programme Grants for Applied Research Programme (Grant Reference Number RP-PG-0707-10162)

Microaerobic Conditions Are Required for Magnetite Formation Within \u3ci\u3eAquaspirillum magnetotacticum\u3c/i\u3e

The amount of magnetite (Fe3O4) within magnetosomes of the microaerophilic bacterium Aquaspirillum magnetotacticum varies with oxygen and nitrogen supply. The development of optical methods for directly measuring cell magnetism in culture samples has enabled us to quantitate bacterial Fe3O4 yields. We measured final cell yields, average cell magnetic moments, and magnetosome yields of growing cells. Cultures were grown with NO3-, NH4+, or both, in sealed, unshaken vials with initial headspace Po2 values ranging from 0 (trace) to 21 kPa. More than 50% of cells had detectable magnetosomes only when grown in the range of 0.5-5.0 kPa O2. Optimum cell magnetism (and Fe3O4 formation) occurred under microaerobic conditions (initial headspace Po2 of 0.5-1 kPa) regardless of the N source. At optimal conditions for Fe3O4 formation, denitrifying cultures produced more of this mineral than those growing with O2 as the sole terminal electron acceptor. This suggests that competition for O2 exists between processes involving respiratory electron disposal and Fe3O4 formation. Oxygen may also be required for Fe3O4 formation by other species of magnetotactic bacteria. Bacterial Fe3O4 appears to persist in sediments after death and lysis of cells. The presence of bacterial Fe3O4 in the fossil and paleomagnetic records may be of use as a retrospective indicator of sedimentation that has occurred in microaerobic waters

Depression and anxiety predict health-related quality of life in chronic obstructive pulmonary disease: systematic review and meta-analysis

Background: The causal association between depression, anxiety, and health-related quality of life (HRQoL) in chronic obstructive pulmonary disease (COPD) is unclear. We therefore conducted a systematic review of prospective cohort studies that measured depression, anxiety, and HRQoL in COPD. Methods: Electronic databases (Medline, Embase, Cumulative Index to Nursing and Allied Health Literature [CINAHL], British Nursing Index and Archive, PsycINFO and Cochrane database) were searched from inception to June 18, 2013. Studies were eligible for inclusion if they: used a nonexperimental prospective cohort design; included patients with a diagnosis of COPD confirmed by spirometry; and used validated measures of depression, anxiety, and HRQoL. Data were extracted and pooled using random effects models. Results: Six studies were included in the systematic review; of these, three were included in the meta-analysis for depression and two were included for the meta-analysis for anxiety. Depression was significantly correlated with HRQoL at 1-year follow-up (pooled r=0.48, 95% confidence interval 0.37–0.57, P<0.001). Anxiety was also significantly correlated with HRQoL at 1-year follow-up (pooled r=0.36, 95% confidence interval 0.23–0.48, P<0.001). Conclusion: Anxiety and depression predict HRQoL in COPD. However, this longitudinal analysis does not show cause and effect relationships between depression and anxiety and future HRQoL. Future studies should identify psychological predictors of poor HRQoL in well designed prospective cohorts with a view to isolating the mediating role played by anxiety disorder and depressio