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BackgroundWearable devices have been widely used in clinical studies to study daily activity patterns, but the analysis remains the major obstacle for researchers.Study ObjectiveThis study proposed a novel method to characterize sleep-activity rhythms using actigraphy and further used it to describe early childhood daily rhythm formation and examine its association with physical development.MethodsWe developed a machine learning-based Penalized Multi-band Learning (PML) algorithm to sequentially infer dominant periodicities based on Fast Fourier Transform (FFT) and further characterize daily rhythms. We implemented and applied the algorithm to Actiwatch data collected from a 262 healthy infant cohort at 6-, 12-, 18-, and 24-month old, with 159, 101, 111, and 141 subjects participating at each time point respectively. Autocorrelation analysis and Fisher’s test for harmonic analysis with Bonferroni correction were applied to compare with PML. The association between activity rhythm features and early childhood motor development, assessed by Peabody Developmental Motor Scales-Second Edition (PDMS-2), was studied through linear regression.ResultsPML results showed that 1-day periodicity is most dominant at 6 and 12 months, whereas 1-day, 1/3-day, and 1/2-day periodicities are most dominant at 18 and 24 months. These periodicities are all significant in Fisher’s test, with 1/4-day periodicity also significant at 12 months. Autocorrelation effectively detected 1-day periodicity but not others. At 6 months, PDMS-2 is associated with assessment seasons. At 12 months, PDMS-2 is associated with seasons and FFT signals at 1/3-day periodicity (PP=.04). In particular, subcategories of stationary, locomotion, and gross motor are associated with FFT signals at 1/3-day periodicity (PConclusionsThe proposed PML algorithm can effectively conduct circadian rhythm analysis using time-series wearable device data. Application of the method effectively characterized sleep-wake rhythm development and identified the association between daily rhythm formation and motor development during early childhood.

The worst performance rule (WPR) is a robust empirical finding reflecting that people’s worst task performance shows stronger relations to cognitive ability compared to their average or best performance. However, recent meta-analytic work has proposed this be renamed the “not-best-performance” rule because mean and worst performance seem to predict cognitive ability to similar degrees (with both predicting ability better than best performance). We re-analyzed data from a previously published latent-variable study to test for worst vs. not-best performance across a variety of reaction time tasks in relation to two cognitive ability constructs: working memory capacity (WMC) and task-unrelated thought (TUT) rate. Using two methods of assessing worst performance—ranked-binning and ex-Gaussian-modeling approaches—we found evidence for both worst and not-best performance rules. WMC followed the not-best performance rule (correlating equivalently with mean and worst RTs) but TUT propensity followed the worst performance rule (correlating more strongly with worst RTs). Additionally, we created a mini-multiverse following different outlier exclusion rules to test the robustness of our findings; our findings remained stable across the different multiverse iterations. We provisionally conclude that the worst performance rule may only arise in relation to cognitive abilities closely linked to (failures of) sustained attention.

Christoff et al. [1] reject our family-resemblances framework for mind-wandering research [2] and instead seek to characterize mind-wandering with a necessary defining feature. As an example, they point to their ‘dynamic framework’ [3] that defines mind-wandering as thoughts that ‘proceed in a relatively free, unconstrained fashion.’ We outline three primary points of disagreement with their commentary and two points of clarification on the family-resemblances framework.

Basket designs are prospective clinical trials that are devised with the hypothesis that the presence of selected molecular features determine a patient's subsequent response to a particular "targeted" treatment strategy. Basket trials are designed to enroll multiple clinical subpopulations to which it is assumed that the therapy in question offers beneficial efficacy in the presence of the targeted molecular profile. The treatment, however, may not offer acceptable efficacy to all subpopulations enrolled. Moreover, for rare disease settings, such as oncology wherein these trials have become popular, marginal measures of statistical evidence are difficult to interpret for sparsely enrolled subpopulations. Consequently, basket trials pose challenges to the traditional paradigm for trial design, which assumes inter-patient exchangeability. The R-package \pkg{basket} facilitates the analysis of basket trials by implementing multi-source exchangeability models. By evaluating all possible pairwise exchangeability relationships, this hierarchical modeling framework facilitates Bayesian posterior shrinkage among a collection of discrete and pre-specified subpopulations. Analysis functions are provided to implement posterior inference of the response rates and all possible exchangeability relationships between subpopulations. In addition, the package can identify "poolable" subsets of and report their response characteristics. The functionality of the package is demonstrated using data from an oncology study with subpopulations defined by tumor histology., 18 pages, 4 figures, 3 tables, submitted to the Journal of Open Source Software

Intimates often discuss the causes of, and solutions to, their relationship problems with their partners, and this information can shape partners' behavior and thus facilitate problem resolution. Partners' ability to encode and later recall such discussions should lead to greater declines in the severity of those problems. This brief report presents the results from a broader longitudinal study in which newlywed couples completed tasks assessing their working memory capacity (WMC), engaged in problem-solving discussions, recalled those discussions after a short delay, and then reported the severity of the problems discussed over the course of a year. Greater WMC among partners was associated with greater declines in the severity of a relationship problem, mediated by partners' recall of the discussion of that problem, suggesting that WMC facilitated the long-term memory encoding of the problem discussion. This study is among the first to suggest that individual differences in basic cognitive abilities may affect conversation processing and recall, and thereby close relationships. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Green et al. (2017) raise two broad concerns with our two studies (Unsworth et al., 2015) showing little association between self-reported video-game experience and cognitive abilities: (a) Our analyses assumed linear gaming-cognition relationships and ignored possible confounding associations among different video-game genres, and (b) the video-game experience questionnaires were problematic and misapplied. We rebut these critiques in this Commentary.

Zoonotic transmission of influenza A virus (IAV) between swine and workers in swine production facilities may play a role in the emergence of novel influenza strains with pandemic potential. Guidelines to prevent transmission of influenza to swine workers have been developed but there is a need for evidence-based decision-making about protective measures such as respiratory protection. A mathematical model was applied to estimate the risk of occupational IAV exposure to swine workers by contact and airborne transmission, and to evaluate the use of respirators to reduce transmission. The Markov model was used to simulate the transport and exposure of workers to IAV in a swine facility. A dose-response function was used to estimate the risk of infection. This approach is similar to methods previously used to estimate the risk of infection in human health care settings. This study uses concentration of virus in air from field measurements collected during outbreaks of influenza in commercial swine facilities, and analyzed by polymerase chain reaction. It was found that spending 25 min working in a barn during an influenza outbreak in a swine herd could be sufficient to cause zoonotic infection in a worker. However, this risk estimate was sensitive to estimates of viral infectivity to humans. Wearing an excellent fitting N95 respirator reduced this risk, but with high aerosol levels the predicted risk of infection remained high under certain assumptions. The results of this analysis indicate that under the conditions studied, swine workers are at risk of zoonotic influenza infection. The use of an N95 respirator could reduce such risk. These findings have implications for risk assessment and preventive programs targeting swine workers. The exact level of risk remains uncertain, since our model may have overestimated the viability or infectivity of IAV. Additionally, the potential for partial immunity in swine workers associated with repeated low-dose exposures or from previous infection with other influenza strains was not considered. Further studies should explore these uncertainties.

We examined the effects of interpolated retrieval from long-term memory (LTM) and short-term memory (STM) on list isolation in dual-list free recall and whether individual differences in working memory capacity (WMC) moderated those effects. Ninety-seven subjects completed study–test trials that included two study lists separated by either an exemplar generation task (LTM retrieval) or a two-back task (STM retrieval). Subjects then completed an externalized free recall task that allowed for the examination of response accessibility and monitoring. Individual differences in WMC were assessed using three complex span tasks: operation span, reading span, and rotation span. Correct recall and intratrial intrusion summary scores showed no effect of interpolated retrieval on either response accessibility or monitoring. However, serial-position curves for correct recall of List 1 showed larger primacy in the two-back than in the exemplar generation task for high-WMC subjects. We interpreted these results from a context change perspective, as showing that interpolated LTM retrieval accelerated context change for subjects who processed the context more effectively. We consider the implications of these findings for models of memory.

We introduce a discrete distribution suggested by curtailed sampling rules common in early-stage clinical trials. We derive the distribution of the smallest number of independent and identically distributed Bernoulli trials needed to observe either s successes or t failures. This report provides a closed-form expression for the mass function, moment generating function, and provides connections to other, standard distributions.

Epidemiologic studies have established associations between various air pollutants and adverse health outcomes for adults and children. Due to high costs of monitoring air pollutant concentrations for subjects enrolled in a study, statisticians predict exposure concentrations from spatial models that are developed using concentrations monitored at a few sites. In the absence of detailed information on when and where subjects move during the study window, researchers typically assume that the subjects spend their entire day at home, school, or work. This assumption can potentially lead to large exposure assignment bias. In this study, we aim to determine the distribution of the exposure assignment bias for an air pollutant (ozone) when subjects are assumed to be static as compared to accounting for individual mobility. To achieve this goal, we use cell-phone mobility data on approximately 400,000 users in the state of Connecticut, USA during a week in July 2016, in conjunction with an ozone pollution model, and compare individual ozone exposure assuming static versus mobile scenarios. Our results show that exposure models not taking mobility into account often provide poor estimates of individuals commuting into and out of urban areas: the average 8-h maximum difference between these estimates can exceed 80 parts per billion (ppb). However, for most of the population, the difference in exposure assignment between the two models is small, thereby validating many current epidemiologic studies focusing on exposure to ozone. Supplementary materials accompanying this paper appear online.

Amyotrophic lateral sclerosis (ALS) is the most common adult-onset neuromuscular disease for which there is currently no effective treatment. The progression of ALS includes loss of motor neurons controlling the voluntary muscles, with much of this loss occurring at the neuromuscular junction. In an effort to better understand changes at the neuromuscular junction, we utilized the wobbler mouse model of motor neuron loss. We examined biceps and end plate morphologies and monitored selected factors involved in end plate function. Structural volumes were determined from 3D reconstructions that were generated for the end plates. Wobbler mice exhibited size reductions of both the muscle fibers and the end plates within the biceps, and we found that the end plate volumes were the most sensitive indicator of the degeneration. Concurrently, we found increases in calcitonin gene-related peptide (CGRP) and its receptor in wobbler biceps and spinal cord. We also found increases in gene expression of two acetylcholine receptors within the wobbler biceps, which may be a result of altered CGRP/CALCRL (calcitonin receptor-like receptor) expression.

In recent years, several laboratory studies have indicated that healthy older adults exhibit a reduction in mind-wandering frequency compared with young adults. However, it is unclear if these findings extend to daily life settings. In the current study, using experience sampling over the course of a week in the daily life of 31 young and 20 older adults, we assessed age-related differences in: (a) mind-wandering frequency, (b) the relationship between affect and mind-wandering frequency, and (c) content of mind wandering. Older adults mind wandered less than young adults in daily life. Across age groups, negative affect was positively associated with mind-wandering occurrence. Finally, older adults reported that their thoughts were more pleasant, interesting, and clear compared with young adults, who had thoughts that were more dreamlike, novel, strange, and racing. Our results provide the first demonstration using thought sampling that older adults exhibit a reduction in mind-wandering frequency in daily life. Implications for current theories of age-related reductions in mind-wandering frequency are discussed. (PsycINFO Database Record

The relations between video-game experience and cognitive abilities were examined in the current study. In two experiments, subjects performed a number of working memory, fluid intelligence, and attention-control measures and filled out a questionnaire about their video-game experience. In Experiment 1, an extreme-groups analysis indicated that experienced video-game players outperformed nonplayers on several cognitive-ability measures. However, in Experiments 1 and 2, when analyses examined the full range of subjects at both the task level and the latent-construct level, nearly all of the relations between video-game experience and cognitive abilities were near zero. These results cast doubt on recent claims that playing video games leads to enhanced cognitive abilities. Statistical and methodological issues with prior studies of video-game experience are discussed along with recommendations for future studies.

A combined experimental–correlational study with a diverse sample (N = 182) from two research\ud sites tested a set of five a priori hypotheses about mind wandering and learning, using a realistic\ud video lecture on introductory statistics. Specifically, the study examined whether students’\ud vulnerability to mind wandering during the lecture would predict learning from, and situational\ud interest in, the video, and also whether longhand note-taking would help reduce mind\ud wandering, at least for some students. Half the subjects took notes during the video, and all\ud were subsequently tested on lecture content without notes. Regression and mediation analyses\ud indicated that: (a) several individual-differences variables (e.g., pretest score, prior math\ud interest, classroom media multitasking habits) uniquely predicted in-lecture mind wandering\ud frequency; (b) although the note-taking manipulation did not reduce mind wandering at the\ud group level, note-taking still reduced mind wandering for some individuals (i.e., those with lower\ud prior knowledge and those who took notes of high quality and quantity); (c) mind wandering\ud uniquely predicted both learning (posttest) and situational interest outcomes above and beyond\ud all other individual-differences variables; (d) moreover, mind wandering significantly mediated\ud the effects of several individual differences; and, finally, (e) not all types of mind wandering\ud were problematic—in fact, off-task reflections about lecture-related topics positively predicted\ud learning. These results, which were generally robust across the two sites, suggest that\ud educationally focused cognitive research may benefit from considering attentional processes\ud during learning as well as cognitive and noncognitive individual differences that affect attention\ud and learning. \ud

Undergraduates ( N = 274) participated in a weeklong daily-life experience-sampling study of mind wandering after being assessed in the lab for executive-control abilities (working memory capacity; attention-restraint ability; attention-constraint ability; and propensity for task-unrelated thoughts, or TUTs) and personality traits. Eight times a day, electronic devices prompted subjects to report on their current thoughts and context. Working memory capacity and attention abilities predicted subjects’ TUT rates in the lab, but predicted the frequency of daily-life mind wandering only as a function of subjects’ momentary attempts to concentrate. This pattern replicates prior daily-life findings but conflicts with laboratory findings. Results for personality factors also revealed different associations in the lab and daily life: Only neuroticism predicted TUT rate in the lab, but only openness predicted mind-wandering rate in daily life (both predicted the content of daily-life mind wandering). Cognitive and personality factors also predicted dimensions of everyday thought other than mind wandering, such as subjective judgments of controllability of thought. Mind wandering in people’s daily environments and TUTs during controlled and artificial laboratory tasks have different correlates (and perhaps causes). Thus, mind-wandering theories based solely on lab phenomena may be incomplete.

The association between working memory capacity (WMC) and the antisaccade task, which requires subjects to move their eyes and attention away from a strong visual cue, supports the claim that WMC is partially an attentional construct (Kane, Bleckley, Conway, & Engle, 2001; Unsworth, Schrock, & Engle, 2004). Specifically, the WMC-antisaccade relation suggests that WMC helps maintain and execute task goals despite interference from habitual actions. Related work has recently shown that mind wandering (McVay & Kane, 2009, 2012a, 2012b) and reaction time (RT) variability (Unsworth, 2015) are also related to WMC and they partially explain WMC's prediction of cognitive abilities. Here, we tested whether mind-wandering propensity and intraindividual RT variation account for WMC's associations with 2 antisaccade-cued choice RT tasks. In addition, we asked whether any influences of WMC, mind wandering, or intraindividual RT variation on antisaccade are moderated by (a) the temporal gap between fixation and the flashing location cue, and (b) whether targets switch sides on consecutive trials. Our quasi-experimental study reexamined a published dataset (Kane et al., 2016) comprising 472 subjects who completed 6 WMC tasks, 5 attentional tasks with mind-wandering probes, 5 tasks from which we measured intraindividual RT variation, and 2 antisaccade tasks with varying fixation-cue gap durations. The WMC-antisaccade association was not accounted for by mind wandering or intraindividual RT variation. WMC's effects on antisaccade performance were greater with longer fixation-to-cue intervals, suggesting that goal activation processes-beyond the ability to control mind wandering and RT variability-are partially responsible for the WMC-antisaccade relation. (PsycINFO Database Record

Background: Little is known about the environmental and public health impact of unconventional natural gas extraction activities, including hydraulic fracturing, that occur near residential areas. Objectives: Our aim was to assess the relationship between household proximity to natural gas wells and reported health symptoms. Methods: We conducted a hypothesis-generating health symptom survey of 492 persons in 180 randomly selected households with ground-fed wells in an area of active natural gas drilling. Gas well proximity for each household was compared with the prevalence and frequency of reported dermal, respiratory, gastrointestinal, cardiovascular, and neurological symptoms. Results: The number of reported health symptoms per person was higher among residents living < 1 km (mean ± SD, 3.27 ± 3.72) compared with > 2 km from the nearest gas well (mean ± SD, 1.60 ± 2.14; p = 0.0002). In a model that adjusted for age, sex, household education, smoking, awareness of environmental risk, work type, and animals in house, reported skin conditions were more common in households < 1 km compared with > 2 km from the nearest gas well (odds ratio = 4.1; 95% CI: 1.4, 12.3; p = 0.01). Upper respiratory symptoms were also more frequently reported in persons living in households < 1 km from gas wells (39%) compared with households 1–2 km or > 2 km from the nearest well (31 and 18%, respectively) (p = 0.004). No equivalent correlation was found between well proximity and other reported groups of respiratory, neurological, cardiovascular, or gastrointestinal conditions. Conclusion: Although these results should be viewed as hypothesis generating, and the population studied was limited to households with a ground-fed water supply, proximity of natural gas wells may be associated with the prevalence of health symptoms including dermal and respiratory conditions in residents living near natural gas extraction activities. Further study of these associations, including the role of specific air and water exposures, is warranted. Citation: Rabinowitz PM, Slizovskiy IB, Lamers V, Trufan SJ, Holford TR, Dziura JD, Peduzzi PN, Kane MJ, Reif JS, Weiss TR, Stowe MH. 2015. Proximity to natural gas wells and reported health status: results of a household survey in Washington County, Pennsylvania. Environ Health Perspect 123:21–26; http://dx.doi.org/10.1289/ehp.1307732

Reductions in function within the serotonin (5HT) neuronal system have long been proposed as etiological factors in depression. Selective serotonin reuptake inhibitors (SSRIs) are the most common treatment for depression, and their therapeutic effect is generally attributed to their ability to increase the synaptic levels of 5HT. Tryptophan hydroxylase 2 (TPH2) is the initial and rate-limiting enzyme in the biosynthetic pathway of 5HT in the CNS, and losses in its catalytic activity lead to reductions in 5HT production and release. The time differential between the onset of 5HT reuptake inhibition by SSRIs (minutes) and onset of their antidepressant efficacy (weeks to months), when considered with their overall poor therapeutic effectiveness, has cast some doubt on the role of 5HT in depression. Mice lacking the gene for TPH2 are genetically depleted of brain 5HT and were tested for a depression-like behavioral phenotype using a battery of valid tests for affective-like disorders in animals. The behavior of TPH2(-/-) mice on the sucrose preference test, tail suspension test, and forced swim test and their responses in the unpredictable chronic mild stress and learned helplessness paradigms was the same as wild-type controls. While TPH2(-/-) mice as a group were not responsive to SSRIs, a subset responded to treatment with SSRIs in the same manner as wild-type controls with significant reductions in immobility time on the tail suspension test, indicative of antidepressant drug effects. The behavioral phenotype of the TPH2(-/-) mouse questions the role of 5HT in depression. Furthermore, the TPH2(-/-) mouse may serve as a useful model in the search for new medications that have therapeutic targets for depression that are outside of the 5HT neuronal system.

Sports-related head impact and injury has become a very highly contentious public health and medico-legal issue. Near-daily news accounts describe the travails of concussed athletes as they struggle with depression, sleep disorders, mood swings, and cognitive problems. Some of these individuals have developed chronic traumatic encephalopathy, a progressive and debilitating neurodegenerative disorder. Animal models have always been an integral part of the study of traumatic brain injury in humans but, historically, they have concentrated on acute, severe brain injuries. This review will describe a small number of new and emerging animal models of sports-related head injury that have the potential to increase our understanding of how multiple mild head impacts, starting in adolescence, can have serious psychiatric, cognitive and histopathological outcomes much later in life. Sports-related head injury (SRHI) has emerged as a significant public health issue as athletes can develop psychiatric and neurodegenerative disorders later in life. Animal models have always been an integral part of the study of human TBI but few existing methods are valid for studying SRHI. In this review, we propose criteria for effective animal models of SRHI. Movement of the head upon impact is judged to be of primary importance in leading to concussion and persistent CNS dysfunction.

The present study explored the associations among several cognitive and creative abilities and expert ratings of jazz improvisational quality. Ten male undergraduate jazz students (8 performance majors, 2 education majors; 5 winds, 3 strings, 1 piano, and 1 drum) performed a video-recorded improvisation with a trio and completed measures of divergent thinking, working memory, and fluid intelligence. Performances were rated for creative quality by 3 expert raters. Students also answered questions regarding their musical background and subjective experience of improvisation. As expected, cumulative practice hours substantially predicted improvisational creativity. Results for the cognitive variables showed mostly negative correlations with improvisation; however, divergent thinking strongly predicted performance quality. We consider these results in the context of the literature on expertise and creativity.

In recent years, there has been a tremendous increase in the number of studies examining mind wandering, and research on the topic has spread widely across various domains of psychological research. As research on the topic of mind wandering has accelerated, the defining features of this conscious state have expanded, and researchers have begun to define mind wandering in conceptually and operationally different ways between – and sometimes even within – studies. Yet, despite clear differences in the definitions adopted, ‘mind wandering’ is often discussed in broad terms, and inferences drawn by researchers are rarely constrained to their specific operational definitions. This practice produces a lack of clarity in our understanding of mind wandering, and it can lead to illusory inconsistencies in the literature. To minimize these problems, we propose that researchers adopt a family-resemblances approach to the investigation of mind wandering, which entails (a) treating mind wandering as a heterogeneous construct and (b) more clearly measuring and describing the specific aspects of the variety of mind wandering that researchers are attempting to investigate. To help move the field forward, we delineate a prototypical case of mind wandering in the broader context of related forms of thought, which should guide the use of the term in future research.

Reports an error in "Individual differences in the executive control of attention, memory, and thought, and their associations with schizotypy" by Michael J. Kane, Matt E. Meier, Bridget A. Smeekens, Georgina M. Gross, Charlotte A. Chun, Paul J. Silvia and Thomas R. Kwapil (

Previous research has identified several cognitive abilities that are important for multitasking, but few studies have attempted to measure a general multitasking ability using a diverse set of multitasks. In the final dataset, 534 young adult subjects completed measures of working memory (WM), attention control, fluid intelligence, and multitasking. Correlations, hierarchical regression analyses, confirmatory factor analyses, structural equation models, and relative weight analyses revealed several key findings. First, although the complex tasks used to assess multitasking differed greatly in their task characteristics and demands, a coherent construct specific to multitasking ability was identified. Second, the cognitive ability predictors accounted for substantial variance in the general multitasking construct, with WM and fluid intelligence accounting for the most multitasking variance compared to attention control. Third, the magnitude of the relationships among the cognitive abilities and multitasking varied as a function of the complexity and structure of the various multitasks assessed. Finally, structural equation models based on a multifaceted model of WM indicated that attention control and capacity fully mediated the WM and multitasking relationship. (PsycINFO Database Record

A large correlational study took a latent-variable approach to the generality of executive control by testing the individual-differences structure of executive-attention capabilities and assessing their prediction of schizotypy, a multidimensional construct (with negative, positive, disorganized, and paranoid factors) conveying risk for schizophrenia. Although schizophrenia is convincingly linked to executive deficits, the schizotypy literature is equivocal. Subjects completed tasks of working memory capacity (WMC), attention restraint (inhibiting prepotent responses), and attention constraint (focusing visual attention amid distractors), the latter 2 in an effort to fractionate the "inhibition" construct. We also assessed mind-wandering propensity (via in-task thought probes) and coefficient of variation in response times (RT CoV) from several tasks as more novel indices of executive attention. WMC, attention restraint, attention constraint, mind wandering, and RT CoV were correlated but separable constructs, indicating some distinctions among "attention control" abilities; WMC correlated more strongly with attentional restraint than constraint, and mind wandering correlated more strongly with attentional restraint, attentional constraint, and RT CoV than with WMC. Across structural models, no executive construct predicted negative schizotypy and only mind wandering and RT CoV consistently (but modestly) predicted positive, disorganized, and paranoid schizotypy; stalwart executive constructs in the schizophrenia literature-WMC and attention restraint-showed little to no predictive power, beyond restraint's prediction of paranoia. Either executive deficits are consequences rather than risk factors for schizophrenia, or executive failures barely precede or precipitate diagnosable schizophrenia symptoms. (PsycINFO Database Record

People’s minds sometimes wander from ongoing activities. Although these experiences can be pleasant and useful, they are often unintentional and precipitate mistakes. In this article, we adopt an individual-differences perspective in considering unwanted mind wandering as an indicator of both momentary failures of and enduring deficiencies in executive-control functions. We describe research that associates normal variation in working memory capacity (WMC)—a cognitive ability that broadly predicts intellectual capabilities and accomplishments—with off-task thinking. In laboratory and daily-life assessments, people with lower WMC mind wander more frequently than do those with higher WMC, at least during demanding tasks. Moreover, the error-proneness of lower-WMC subjects seems to arise partly from their vulnerability to mind wandering. Executive control over one’s thoughts therefore seems to contribute to the effective regulation of behavior.

A combined experimental, individual-differences, and thought-sampling study tested the predictions of executive attention (e.g., Engle & Kane, 2004) and coordinative binding (e.g., Oberauer, Sus, Wilhelm, & Sander, 2007) theories of working memory capacity (WMC). We assessed 288 subjects' WMC and their performance and mind-wandering rates during a sustained-attention task; subjects completed either a go/no-go version requiring executive control over habit or a vigilance version that did not. We further combined the data with those from McVay and Kane (2009) to (1) gauge the contributions of WMC and attentional lapses to the worst performance rule and the tail, or t parameter, of reaction time (RT) distributions; (2) assess which parameters from a quantitative evidence-accumulation RT model were predicted by WMC and mind-wandering reports; and (3) consider intrasubject RT patterns—particularly, speeding—as potential objective markers of mind wandering. We found that WMC predicted action and thought control in only some conditions, that attentional lapses (indicated by task-unrelated-thought reports and drift-rate variability in evidence accumulation) contributed to t, performance accuracy, and WMC's association with them and that mind-wandering experiences were not predicted by trial-to-trial RT changes, and so they cannot always be inferred from objective performance measures.

Some people are better readers than others, and this variation in comprehension ability is predicted by measures of working memory capacity (WMC). The primary goal of this study was to investigate the mediating role of mind wandering experiences in the association between WMC and normal individual differences in reading comprehension, as predicted by the executive-attention theory of WMC (e.g., Engle & Kane, 2004). We used a latent-variable, structural-equation-model approach, testing skilled adult readers on three WMC span tasks, seven varied reading comprehension tasks, and three attention-control tasks. Mind wandering was assessed using experimenter-scheduled thought probes during four different tasks (two reading, two attention-control tasks). The results support the executive-attention theory of WMC. Mind wandering across the four tasks loaded onto a single latent factor, reflecting a stable individual difference. Most importantly, mind wandering was a significant mediator in the relationship between WMC and reading comprehension, suggesting that the WMC-comprehension correlation is driven, in part, by attention control over intruding thoughts. We discuss implications for theories of WMC, attention control, and reading comprehension.

Neuropsychiatric disorders characterized by behavioral disinhibition, including disorders of compulsivity (e.g. obsessive-compulsive disorder; OCD) and impulse-control (e.g. impulsive aggression), are severe, highly prevalent and chronically disabling. Treatment options for these diseases are extremely limited. The pathophysiological bases of disorders of behavioral disinhibition are poorly understood but it has been suggested that serotonin dysfunction may play a role. Mice lacking the gene encoding brain tryptophan hydroxylase 2 (Tph2-/-), the initial and rate-limiting enzyme in the synthesis of serotonin, were tested in numerous behavioral assays that are well known for their utility in modeling human neuropsychiatric diseases. Mice lacking Tph2 (and brain 5HT) show intense compulsive and impulsive behaviors to include extreme aggression. The impulsivity is motor in form and not cognitive because Tph2-/- mice show normal acquisition and reversal learning on a spatial learning task. Restoration of 5HT levels by treatment of Tph2-/- mice with its immediate precursor 5-hydroxytryptophan attenuated compulsive and impulsive-aggressive behaviors. Surprisingly, in Tph2-/- mice, the lack of 5HT was not associated with anxiety-like behaviors. The results indicate that 5HT mediates behavioral disinhibition in the mammalian brain independent of anxiogenesis.

Individual differences in working memory capacity are related to a variety of behaviors both within and outside of the lab. Recently developed automated complex span tasks have contributed to increasing our knowledge concerning working memory capacity by making valid and reliable assessments freely available for use by researchers. Combining the samples from three testing locations yielded data from over 6,000 young adult participants who performed at least one of three such tasks (Operation, Symmetry, and Reading Span). Normative data are presented here for researchers interested in applying cutoffs for their own applications, and information on the validity and reliability of the tasks is also reported. In addition, the data were analyzed as a function of sex and college status. While automated complex span tasks are just one way to measure working memory capacity, the use of a standardized procedure for administration and scoring greatly facilitates comparison across studies.

Repetitive mild traumatic brain injury (mTBI) represents a major public health problem. Many individuals who suffer repetitive mTBIs suffer from Post-Concussion Syndrome, a constellation of neuropsychiatric symptoms that includes depression, anxiety, and problems with memory and other cognitive processes. Significantly, Post-Concussion Syndrome is resistant to existing therapeutic strategies. To provide better treatment options for this patient population, the underlying pathophysiology of repetitive mTBI must be understood. A first step in this process is the establishment of an in vitro model system that recapitulates the biological changes that occur in the brains of repetitively injured humans. The availability of a model with immortalized cell lines would remove the considerable barriers of time, expense, and difficulties with genetic manipulation that exist with the use of primary neuronal cultures. Here we report the development and functional characterization of an in vitro laboratory model of repetitive TBI using immortalized neuronal cell lines. These results indicate that the moderate, repetitive injury reduces viability, numbers and lengths of neurites, and that the neuronal loss mechanism includes caspase activation.

Simple and complex span tasks are widely thought to measure related but separable memory constructs. Recently, however, research has demonstrated that simple and complex span tasks may tap, in part, the same construct because both similarly predict performance on measures of fluid intelligence (Gf) when the number of items retrieved from secondary memory (SM) is equated (Unsworth & Engle, Journal of Memory and Language 54:68–80 2006). Two studies (n = 105 and n = 152) evaluated whether retrieval from SM is influenced by individual differences in the use of encoding strategies during span tasks. Results demonstrated that, after equating the number of items retrieved from SM, simple and complex span performance similarly predicted Gf performance, but rates of effective strategy use did not mediate the span-Gf relationships. Moreover, at the level of individual differences, effective strategy use was more highly related to complex span performance than to simple span performance. Thus, even though individual differences in effective strategy use influenced span performance on trials that required retrieval from SM, strategic behavior at encoding cannot account for the similarities between simple and complex span tasks.

Goal neglect is the phenomenon of failing to execute the momentary demands of a task despite understanding and being able to recall the task instructions. Successful goal maintenance is more likely to occur in adults with high working memory capacity (WMC) who can keep rules mentally accessible while performing the task. The current study predicted that goal neglect would also be related to WMC in children. It assessed thirty-seven 4-year-old and twenty-eight 6-year-old children on the goal neglect version of the Dimensional Change Card Sort, and 3 tasks that measure WMC. As predicted, children with higher WMC scores were more likely to maintain goals adequately for task performance. The findings are consistent with a 2-factor model of working memory and its development.

Key Points Question How substantial are cancer disparities on the basis of county levels of income, and what are the factors that may mediate the disparities? Findings In this cross-sectional study of 3135 US counties, cancer death rates varied significantly in counties of different income levels, with a mean cancer death rate per 100 000 person-years of 185.9 in high-income counties, 204.9 in medium-income counties, and 229.7 in low-income counties. The strongest possible mediators were health risk behaviors, cost and quality of clinical care, and food insecurity. Meaning There are multiple county-level factors that may serve as mediators of cancer disparities and that may be targeted by future efforts to achieve equity in cancer outcomes., This cross-sectional study uses death records from the US National Center for Health Statistics to investigate the association between cancer death rates and county-level median household income and identifies potential mediating factors of this association., Background There are concerns about the degree to which county income level might underlie the stark disparities in cancer death rates among US counties; at the same time, there is uncertainty about the factors that may mediate the disparities. Objectives To assess county-level cancer death rates and to identify possible mediators of the association between county-level median incomes and cancer death rates. Design, Setting, and Participants Cross-sectional study using death records from the National Center for Health Statistics in 2014, with data collected and analyzed between October 1, 2016, and July 31, 2017. All US counties and county equivalents were included. Exposures County-level median household income. Main Outcomes and Measures County-level age-standardized cancer death rate. Results In 3135 counties, median incomes ranged from $22 126 to $121 250 per year. Low-income counties (median income, $33 445) vs high-income counties (median income, $55 780) had higher proportions of residents who were non-Hispanic black, lived in rural areas, or reported poor or fair health. The mean (SD) cancer death rate was 185.9 (24.4) per 100 000 person-years in high-income counties, compared with 204.9 (26.3) and 229.7 (32.9) per 100 000 person-years in medium- and low-income counties, respectively. In mediation models, health risk behaviors (smoking, obesity, and physical inactivity); clinical care factors (unaffordable care and low-quality care); health environments (food insecurity); and health policies (state smoke-free laws and Medicaid payment rates) in aggregate accounted for more than 80% of the income-related disparity. The strongest possible mediators were food insecurity (explaining 19.1% [95% CI, 12.5%-26.5%] of the association between county incomes and cancer deaths), low-quality care (17.9%; 95% CI, 14.0%-21.8%), smoking (12.7%; 95% CI, 9.4%-15.6%), and physical inactivity (12.2%; 95% CI, 9.4%-15.6%). Conclusions and Relevance There are wide gaps in cancer death rates between low-, medium-, and high-income counties. Future studies are needed to assess whether targeting the possible mediators might ameliorate the substantial socioeconomic cancer disparities.

In an experience-sampling study that bridged laboratory, ecological, and individual-differences approaches to mind-wandering research, 72 subjects completed an executive-control task with periodic thought probes (reported by McVay & Kane, 2009) and then carried PDAs for a week that signaled them eight times daily to report immediately whether their thoughts were off task. Subjects who reported more mind wandering during the laboratory task endorsed more mind-wandering experiences during everyday life (and were more likely to report worries as off-task thought content). We also conceptually replicated laboratory findings that mind wandering predicts task performance: Subjects rated their daily-life performance to be impaired when they reported off-task thoughts, with greatest impairment when subjects’ mind wandering lacked metaconsciousness. The propensity to mind wander appears to be a stable cognitive characteristic and seems to predict performance difficulties in daily life, just as it does in the laboratory

On the basis of the executive-attention theory of working memory capacity (WMC; e.g., M. J. Kane, A. R. A. Conway, D. Z. Hambrick, & R. W. Engle, 2007), the authors tested the relations among WMC, mind wandering, and goal neglect in a sustained attention to response task (SART; a go/no-go task). In 3 SART versions, making conceptual versus perceptual processing demands, subjects periodically indicated their thought content when probed following rare no-go targets. SART processing demands did not affect mind-wandering rates, but mind-wandering rates varied with WMC and predicted goal-neglect errors in the task; furthermore, mind-wandering rates partially mediated the WMC–SART relation, indicating that WMC-related differences in goal neglect were due, in part, to variation in the control of conscious thought.

Recent findings suggest that exerting executive control influences responses to moral dilemmas. In our study, subjects judged how morally appropriate it would be for them to kill one person to save others. They made these judgments in 24 dilemmas that systematically varied physical directness of killing, personal risk to the subject, inevitability of the death, and intentionality of the action. All four of these variables demonstrated main effects. Executive control was indexed by scores on working-memory-capacity (WMC) tasks. People with higher WMC found certain types of killing more appropriate than did those with lower WMC and were more consistent in their judgments. We also report interactions between manipulated variables that implicate complex emotion-cognition integration processes not captured by current dual-process views of moral judgment.

Should executive control, as indicated by working memory capacity (WMC) and mind-wandering propensity, help or hinder creativity? Sustained and focused attention should help guide a selective search of solution-relevant information in memory and help inhibit uncreative, yet accessible, ideas. However, unfocused attention and daydreaming should allow mental access to more loosely relevant concepts, remotely linked to commonplace solutions. Three individual-differences studies inserted incubation periods into one or two divergent thinking tasks and tested whether WMC (assessed by complex span tasks) and incubation-period mind wandering (assessed as probed reports of task-unrelated thought [TUT]) predicted post-incubation performance. Retrospective self-reports of Openness (Experiment 2) and mind-wandering and daydreaming propensity (Experiment 3) complemented our thought-probe assessments of TUT. WMC did not correlate with creativity in divergent thinking, whereas only the questionnaire measure of daydreaming, but not probed thought reports, weakly predicted creativity; the fact that in-the-moment TUTs did not correlate divergent creativity is especially problematic for claims that mind-wandering processes contribute to creative cognition. Moreover, the fact that WMC tends to strongly predict analytical problem solving and reasoning, but may not correlate with divergent thinking, provides a useful boundary condition for defining WMC's nomological net. On balance, our data provide no support for either benefits or costs of executive control for at least one component of creativity.

Attention, suggestion, context and expectation can all exert top-down influence on bottom-up processes (e.g., stimulus-driven mechanisms). Identifying the functional neuroanatomy that subserves top-down influences on sensory information processing can unlock the neural substrates of how suggestion can modulate behavior. Using functional magnetic resonance imaging (fMRI), we scanned 10 healthy participants (five men) viewing five bistable figures. Participants received a directional cue to perceive a particular spatial orientation a few seconds before the bistable figure appeared. After presentation, participants pressed a button to indicate their locking into the one desired orientation of the two possible interpretations. Participants additionally performed tests of impulse control and sustained attention. Our findings reveal the role of specific frontostriatal structures in selecting a particular orientation for bistable figures, including dorsolateral prefrontal regions and the putamen. Additional contrasts further bolstered the role of the frontostriatal system in the top-down processing of competing visual perceptions. Separate correlations of behavioral variables with fMRI activations support the idea that the frontostriatal system may mediate attentional control when selecting among competing visual perceptions. These results may generalize to other psychological functions. With special relevance to clinical neuroscience and applications involving attention, expectation and suggestion (e.g., hypnosis), our results address the importance of frontostriatal circuitry in behavioral modulation.

We present genetically identical twin patients who experienced late-onset migraine with visual and somatosensory auras and later developed hemiplegic migraines associated with severe cortical oedema and enhancement. Both positron emission tomography and electroencephalography showed an increase in activity contralateral to the hemiplegic side. Brain biopsy during the attack showed reactive astrogliosis and microgliosis. Mutations in CACNA1A, ATP1A2, SLC1A3 and NOTCH3 were ruled out by sequencing. This report shows the clinical and genetic evaluation of a severe form of familial hemiplegic migraine as well as the evolution of the imaging changes.

Three experiments tested whether a modified version of the Clustered Conceptual Span task (H. J. Haarmann, E. J. Davelaar, & M. Usher, 2003), which ostensibly requires active maintenance of semantic representations, predicted individual differences in higher-order cognitive abilities better than short-term memory (STM) span tasks or nonsemantic versions of the "Conceptual" task did. Nonsemantic Conceptual tasks presented short word lists clustered by color, first letter, or initial vowel sound, and cued subjects to recall only 1 of 3 clusters from each list; the Semantic task clustered words by taxonomic category. The Semantic Conceptual task generally failed to predict incremental variance in either verbal abilities or general fluid intelligence beyond the other Conceptual tasks or STM span tasks. Although the Semantic task showed a stronger relation to working memory span tasks than did the nonsemantic tasks (Experiment 3), that stronger relation did not translate into strong prediction of cognitive individual differences.

An experience-sampling study of 124 undergraduates, pretested on complex memory-span tasks, examined the relation between working memory capacity (WMC) and the experience of mind wandering in daily life. Over 7 days, personal digital assistants signaled subjects eight times daily to report immediately whether their thoughts had wandered from their current activity, and to describe their psychological and physical context. WMC moderated the relation between mind wandering and activities' cognitive demand. During challenging activities requiring concentration and effort, higher-WMC subjects maintained on-task thoughts better, and mind-wandered less, than did lower-WMC subjects. The results were therefore consistent with theories of WMC emphasizing the role of executive attention and control processes in determining individual differences and their cognitive consequences.