Longitudinal development of visual working memory precision in childhood and early adolescence

© 2016. Visual working memory (VWM) is the ability to hold in mind visual information for brief periods of time. The current study investigated VWM precision development longitudinally. Participants (N = 40, aged 7-11 years) completed delayed reproduction sequential VWM tasks at baseline and two years later. Results show age-related improvement in recall precision on both 1-item and 3-item VWM tasks, suggesting development during childhood and early adolescence in the resolution with which both single and multiple items are stored in VWM. Probabilistic modelling of response distribution data suggests age-related improvement in precision is attributable to a specific decrease in the variability (noisiness) of stored feature representations. This highlights a novel developmental mechanism which may underlie longitudinal improvement in VWM performance, crucially without invoking improvement in the number of items that can be stored. VWM precision provides a sensitive metric with which to track developmental changes longitudinally, shedding light on underlying cognitive mechanisms

Friendship and self-harm:A retrospective qualitative study of young adults' experiences of supporting a friend who self-harmed during adolescence

Introduction: Self-harm amongst young people is becoming increasinglyprevalent. Understanding, responding to, and supporting young people who self-harm is vital. Friends are typically the first and sometimes the only source of support sought by adolescents who self-harm. Despite their important role asconfidants, friends’ perspectives and experiences remain poorly understood.Methods: We conducted retrospective qualitative semi-structured interviews,prompted by an adapted version of the Card Sort Task for Self-Harm (CaTS-FF), about the experiences of nine female young adults (18-20 years old) whosupported a friend who self-harmed during adolescence. Data were analyzedusing thematic analysis.Results: Four themes were developed: (1) “I did not realize my friend was on theroad to self-harm”: Friends’ reactions to self-harm; (2) “That’s what friends do”: the role of friends; (3) The impact of supporting a friend who self-harms; and (4) “They were quite formative years”: reflecting on growth through the experience.Discussion: The present findings highlight the complex experiences of youngpeople supporting a friend who self-harms. Despite being willing to take on therole of a supporter, participants experienced a range of difficult emotions andconsequences. The temporal transition running through the four themes reflectsthe evolving nature of participants’ attitudes, knowledge, and friendships. Overall, results highlight the unmet needs of adolescents supporting young people who self-harm, as well as identifying potential pathways to “support the supporters” toward resilience

Upper and lower lumbar segments move differently during sit-to-stand

Sit-to-stand (STS) is a functional dynamic task, requiring movement of the lumbar spine, however, little is known about whether regional differences or between-gender differences exist during this task. The aim of this study was to confirm whether kinematic differences existed within regions of the lumbar spine during STS and also to determine whether between-gender differences were evident. An electromagnetic measurement device, recording at 25 Hz, determined how different lumbar spine regions (combined, lower and upper) moved during STS in 29 healthy participants (16 males, 13 females). Discrete outputs including mean range of motion (ROM), maximum and minimum were calculated for each lumbar spine region. Analyses of covariance (ANCOVA) with repeated measures were used to determine whether regional differences and between-gender differences were evident in the lumbar spine during STS. With the lumbar spine modelled as two segments, the lower lumbar (LLx) and upper lumbar (ULx) regions made different contributions to STS: F1, 27=21.8; p < 0.001. No between-gender differences were found with the lumbar spine modelled as a single region (combined lumbar: CLx), however, modelled as two regions there was a significant gender difference between the LLx and ULx regions: F1, 27=7.3 (p=0.012). The results indicate that modelling the lumbar spine as a single segment during STS does not adequately represent lumbar spine kinematics and there are important gender differences. These findings also need to be considered when investigating STS in clinical populations

Emotional Mental Imagery as Simulation of Reality: Fear and Beyond—A Tribute to Peter Lang

AbstractThis article pays tribute to the seminal paper by Peter J. Lang (1977; this journal), “Imagery in Therapy: Information Processing Analysis of Fear.” We review research and clinical practice developments in the past five decades with reference to key insights from Lang’s theory and experimental work on emotional mental imagery. First, we summarize and recontextualize Lang’s bio-informational theory of emotional mental imagery (1977, 1979) within contemporary theoretical developments on the function of mental imagery. Second, Lang’s proposal that mental imagery can evoke emotional responses is evaluated by reviewing empirical evidence that mental imagery has a powerful impact on negative as well as positive emotions at neurophysiological and subjective levels. Third, we review contemporary cognitive and behavioral therapeutic practices that use mental imagery, and consider points of extension and departure from Lang’s original investigation of mental imagery in fear-extinction behavior change. Fourth, Lang’s experimental work on emotional imagery is revisited in light of contemporary research on emotional psychopathology-linked individual differences in mental imagery. Finally, key insights from Lang’s experiments on training emotional response during imagery are discussed in relation to how specific techniques may be harnessed to enhance adaptive emotional mental imagery training in future research

Bipolar risk and mental imagery susceptibility in a representative sample of Chinese adults residing in the community

BACKGROUND: We need to better understand the cognitive factors associated with risk for bipolar disorders. Recent research suggests that increased susceptibility to mental imagery may be one such factor. However, since this research was primarily conducted with Western students and at a single time-point, it is not known whether the relationship between imagery susceptibility and bipolar symptoms exists across cultures or within the general community, or whether this relationship remains stable over time. AIM: This study evaluated whether Chinese adults identified as being at high (HR) versus low (LR) risk of developing bipolar disorders showed greater mental imagery susceptibility. We aimed to test whether such a relationship was stable over time by measuring imagery characteristics at baseline and at the 7-week follow-up. METHOD: This prospective study recruited a community sample of N = 80 Chinese adults screened for the absence of neurotic and psychotic disorders. The sample was split into HR (n = 18) and LR (n = 62) groups at baseline based on a criterion cut-off score on a measure of hypomania, the Mood Disorder Questionnaire (MDQ). Participants completed measures of imagery susceptibility and its impact: the Spontaneous Use of Imagery Scale (SUIS) and the Impact of Future Events Scale (IFES), at baseline and 7 weeks later. RESULTS: HR group reported greater tendency to use imagery in daily life (SUIS) and greater emotional impact of prospective imagery (IFES) than LR group at baseline. These results remained stable at follow-up. CONCLUSION: This study provides preliminary evidence for increased susceptibility to mental imagery in individuals at high risk of bipolar disorders recruited from a community sample of Chinese adults. This extends previous research in Western student samples suggesting that imagery (both levels of use and its emotional impact) may be a cognitive factor with cross-cultural relevance that is stable over time

Social interaction and pain:An arctic expedition

Complex human behaviour can only be understood within its social environment. However, disentangling the causal links between individual outcomes and social network position is empirically challenging. We present a research design in a closed real-world setting with high-resolution temporal data to understand this interplay within a fundamental human experience – physical pain. Study participants completed an isolated 3-week hiking expedition in the Arctic Circle during which they were subject to the same variation in environmental conditions and only interacted amongst themselves. Adolescents provided daily ratings of pain and social interaction partners. Using longitudinal network models, we analyze the interplay between social network position and the experience of pain. Specifically, we test whether experiencing pain is linked to decreasing popularity (increasing isolation), whether adolescents prefer to interact with others experiencing similar pain (homophily), and whether participants are increasingly likely to report similar pain as their interaction partners (contagion). We find that reporting pain is associated with decreasing popularity – interestingly, this effect holds for males only. Further exploratory analyses suggest this is at least partly driven by males withdrawing from contact with females when in pain, enhancing our understanding of pain and masculinity. Contrary to recent experimental and clinical studies, we found no evidence of pain homophily or contagion in the expedition group

Distinct Effects of Adipose-derived Stem Cells and Adipocytes on Normal and Cancer Cell Hierarchy

Adipose-derived stem cells (ASC) have received considerable attention in oncology because of the known direct link between obesity and cancer as well as the use of ASCs in reconstructive surgery after tumor ablation. Previous studies have documented how cancer cells commandeer ASCs to support their survival by altering extracellular matrix composition and stiffness, migration, and metastasis. This study focused on delineating the effects of ASCs and adipocytes on the self-renewal of stem/progenitor cells and hierarchy of breast epithelial cells. The immortalized breast epithelial cell line MCF10A, ductal carcinoma in situ (DCIS) cell lines MCF10DCIS.com and SUM225, and MCF10A-overexpressing SRC oncogene were examined using a mammosphere assay and flow cytometry for the effects of ASCs on their self-renewal and stem-luminal progenitor-differentiated cell surface marker profiles. Interestingly, ASCs promoted the self-renewal of all cell types except SUM225. ASC coculture or treatment with ASC conditioned media altered the number of CD49fhigh/EpCAMlow basal/stem-like and CD49fmedium/EpCAMmedium luminal progenitor cells. Among multiple factors secreted by ASCs, IFNγ and hepatocyte growth factor (HGF) displayed unique actions on epithelial cell hierarchy. IFNγ increased stem/progenitor-like cells while simultaneously reducing the size of mammospheres, whereas HGF increased the size of mammospheres with an accompanying increase in luminal progenitor cells. ASCs expressed higher levels of HGF, whereas adipocytes expressed higher levels of IFNγ. As luminal progenitor cells are believed to be prone for transformation, IFNγ and HGF expression status of ASCs may influence susceptibility for developing breast cancer as well as on outcomes of autologous fat transplantation on residual/dormant tumor cells. Implications: This study suggests that the ratio of ASCs to adipocytes influences cancer cell hierarchy, which may impact incidence and progression

Characterization of reward and effort mechanisms in apathy

AbstractApathy is a common but poorly understood condition with a wide societal impact observed in several brain disorders as well as, to some extent, in the normal population. Hence the need for better characterization of the underlying mechanisms. The processes by which individuals decide to attribute physical effort to obtain rewards might be particularly relevant to relate to apathy traits. Here, we designed two paradigms to assess individual differences in physical effort production and effort-based decision-making and their relation to apathy in healthy people. Apathy scores were measured using a modified version of the Lille Apathy Rating Scale, suitable for use in a non-clinical population.In the first study, apathy scores were correlated with the degree to which stake (reward on offer) and difficulty level impacts on physical effort production. Individuals with relatively high apathy traits showed an increased modulation of effort while more motivated individuals generally exerted greater force across different levels of stake. To clarify the underlying mechanisms for this behavior, we designed a second task that allows independent titration of stake and effort levels for which subjects are willing to engage in an effortful response to obtain a reward. Our results suggest that apathy traits in the normal population are related to the way reward subjectively affects the estimation of effort costs, and more particularly manifest as decreased willingness to exert effort when rewards are small, or below threshold. The tasks we introduce here may provide useful tools to further investigate apathy in clinical populations

Relationship Reciprocation Modulates Resource Allocation in Adolescent Social Networks: Developmental Effects

Adolescence is characterized as a period of social reorientation toward peer relationships, entailing the emergence of sophisticated social abilities. Two studies (Study 1: N = 42, ages 13–17; Study 2: N = 81, ages 13–16) investigated age group differences in the impact of relationship reciprocation within school-based social networks on an experimental measure of cooperation behavior. Results suggest development between mid- and late adolescence in the extent to which reciprocation of social ties predicted resource allocation. With increasing age group, investment decisions increasingly reflected the degree to which peers reciprocated feelings of friendship. This result may reflect social-cognitive development, which could facilitate the ability to navigate an increasingly complex social world in adolescence and promote positive and enduring relationships into adulthood

Impulsivity and Rapid Decision-Making for Reward

Impulsivity is a feature of many brain disorders. Although often defined as the predisposition to act with an inadequate degree of deliberation, forethought, or control, it has proven difficult to measure. This may in part be due to the fact that it is a multifaceted construct, with impulsive decisions potentially arising as a result of a number of underlying mechanisms. Indeed, a “functional” degree of impulsivity may even promote effective behavior in healthy participants in a way that can be advantageous under certain circumstances. Although many tasks have been developed to study impulsivity, few examine decisions made rapidly, for time-sensitive rewards. In the current study we examine behavior in 59 adults on a manual “Traffic Light” task which requires participants to take risks under time pressure, if they are to maximize reward. We show that behavioral variables that index rapid anticipatory responding in this paradigm are correlated with one, specific self-report measure of impulsivity: “lack of premeditation” on the UPPS Impulsive Behavior Scale. Participants who scored more highly on this subscale performed better on the task. Moreover, anticipatory behavior reduced significantly with age (18–79 years), an effect that continued to be upheld after correction for potential age differences in the ability to judge the timing of responses. Based on these findings, we argue that the Traffic Light task provides a parametric method to study one aspect of impulsivity in health and disease: namely, rapid decision-making in pursuit of risky, time-sensitive rewards