SCoT: a Python toolbox for EEG source connectivity

Analysis of brain connectivity has become an important research tool in neuroscience. Connectivity can be estimated between cortical sources reconstructed from the electroencephalogram (EEG). Such analysis often relies on trial averaging to obtain reliable results. However, some applications such as brain-computer interfaces (BCIs) require single-trial estimation methods. In this paper, we present SCoT—a source connectivity toolbox for Python. This toolbox implements routines for blind source decomposition and connectivity estimation with the MVARICA approach. Additionally, a novel extension called CSPVARICA is available for labeled data. SCoT estimates connectivity from various spectral measures relying on vector autoregressive (VAR) models. Optionally, these VAR models can be regularized to facilitate ill posed applications such as single-trial fitting. We demonstrate basic usage of SCoT on motor imagery (MI) data. Furthermore, we show simulation results of utilizing SCoT for feature extraction in a BCI application. These results indicate that CSPVARICA and correct regularization can significantly improve MI classification. While SCoT was mainly designed for application in BCIs, it contains useful tools for other areas of neuroscience. SCoT is a software package that (1) brings combined source decomposition and connectivtiy estimation to the open Python platform, and (2) offers tools for single-trial connectivity estimation. The source code is released under the MIT license and is available online at github.com/SCoT-dev/SCoT

Collateral and collateral-adjacent hyperemic vascular resistance changes and the ipsilateral coronary flow reserve: Documentation of a mechanism causing coronary steal in patients with coronary artery disease

Objectives: The goal of this clinical study was to assess the influence of hyperemic ipsilateral, collateral and contralateral vascular resistance changes on the coronary flow velocity reserve (CFVR) of the collateral-receiving (i.e. ipsilateral) artery, and to test the validity of a model describing the development of collateral steal. Methods: In 20 patients with one- to two-vessel coronary artery disease (CAD) undergoing angioplasty of one stenotic lesion, adenosine induced intracoronary (i.c.) CFVR during vessel patency was measured using a Doppler guidewire. During stenosis occlusion, simultaneous i.c. distal ipsilateral flow velocity and pressure (Poccl, using a pressure guidewire) as well as contralateral flow velocity measurements via a third i.c. wire were performed before and during intravenous adenosine. From those measurements and simultaneous mean aortic pressure (Pao), a collateral flow index (CFI), and the ipsilateral, collateral, and contralateral vascular resistance index (Ripsi, Rcoll, Rcontra) were calculated. The study population was subdivided into groups with CFI<0.15 and with CFI≥0.15. Results: The percentage-diameter coronary artery stenosis (%-S) to be dilated was similar in the two groups: 78±10% versus 82±12% (NS). CFVR was not associated with %-S. In the group with CFI≥0.15 but not with CFI<0.15, CFVR was directly and inversely associated with Rcoll and Rcontra, respectively. Conclusions: A hemodynamic interaction between adjacent vascular territories can be documented in patients with CAD and well developed collaterals among those regions. The CFVR of a collateralized region may, thus, be more dependent on hyperemic vascular resistance changes of the collateral and collateral-supplying area than on the ipsilateral stenosis severity, and may even fall below

Pilot Study of Endurance Runners and Brain Responses Associated with Delay Discounting

International Journal of Exercise Science 10(5): 690-701, 2017. High levels of endurance training have been associated with potentially negative health outcomes and addictive-like symptoms such as exercise in the presence of injury and higher levels of impulsivity. This pilot study examined the relationships among self-report measures of addictive symptoms related to exercise and behavioral and neural measures of impulsivity in endurance runners. We hypothesized endurance runners would have increased preference for immediate rewards and greater activation of cognitive control regions when making decisions involving delayed rewards. Twenty endurance runners (at least 20 miles/week) were recruited to undergo measures of self-report exercise addiction symptoms, impulsive decision-making (delay discounting) and functional magnetic resonance imaging (fMRI). During behavioral and fMRI examinations, participants chose between a small hypothetical amount of money given immediately ($0 – 100) compared to a larger hypothetical amount of money ($100) given after a delay (2-12 weeks). On half of the trials participants were instructed that if they chose the delayed reward they would not be able to exercise during the delay period. Eighteen participants were included in the analysis. Results indicated that 94% of endurance runners reported high levels of exercise addiction symptoms, and 44% were “at-risk” for exercise addiction. In addition, endurance runners demonstrated increased preference for immediately available compared to delayed rewards (p \u3c 0.001) and greater recruitment of cognitive control regions (dorsomedial prefrontal cortex and anterior cingulate) when making decisions involving rewards when exercise was delayed (p \u3c 0.05). Together, these results indicate that endurance runners not only report addictive symptoms related to exercise, but also demonstrate addictive-like behaviors

KTR: An efficient key management scheme for secure data access control in wireless broadcast services recovery

Recent growth in brain-computer interface (BCI) research has increased pressure to report improved performance. However, different research groups report performance in different ways. Hence, it is essential that evaluation procedures are valid and reported in sufficient detail. In this chapter we give an overview of available performance measures such as classification accuracy, cohen’s kappa, information transfer rate (ITR), and written symbol rate. We show how to distinguish results from chance level using confidence intervals for accuracy or kappa. Furthermore, we point out common pitfalls when moving from offline to online analysis and provide a guide on how to conduct statistical tests on (BCI) results

Augmenting communication, emotion expression and interaction capabilities of individuals with cerebral palsy

!c 2014Verlag der Technischen Universit¨at Graz. Providing individuals with cerebral palsy (CP) tools to communicate and interact with the environment independently and reliably since childhood would allow for a more active participation in education and social life. We outline first steps towards the development of such a hybrid brain-computer interface-based (BCI) communication tool.This work was supported by the FP7 Framework EU Research Project ABC (No. 287774). This paper only reflects the authors views and funding agencies are not liable for any use that may be made of the information contained herein.Peer Reviewe

Dementia risk and dynamic response to exercise: A non-randomized clinical trial

A grant from the One-University Open Access Fund at the University of Kansas was used to defray the author's publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.Background Physical exercise may support brain health and cognition over the course of typical aging. The goal of this nonrandomized clinical trial was to examine the effect of an acute bout of aerobic exercise on brain blood flow and blood neurotrophic factors associated with exercise response and brain function in older adults with and without possession of the Apolipoprotein epsilon 4 (APOE4) allele, a genetic risk factor for developing Alzheimer’s. We hypothesized that older adult APOE4 carriers would have lower cerebral blood flow regulation and would demonstrate blunted neurotrophic response to exercise compared to noncarriers. Methods Sixty-two older adults (73±5 years old, 41 female [67%]) consented to this prospectively enrolling clinical trial, utilizing a single arm, single visit, experimental design, with post-hoc assessment of difference in outcomes based on APOE4 carriership. All participants completed a single 15-minute bout of moderate-intensity aerobic exercise. The primary outcome measure was change in cortical gray matter cerebral blood flow in cortical gray matter measured by magnetic resonance imaging (MRI) arterial spin labeling (ASL), defined as the total perfusion (area under the curve, AUC) following exercise. Secondary outcomes were changes in blood neurotrophin concentrations of insulin-like growth factor-1 (IGF-1), vascular endothelial growth factor (VEGF), and brain derived neurotrophic factor (BDNF). Results Genotyping failed in one individual (n = 23 APOE4 carriers and n = 38 APOE4 non-carriers) and two participants could not complete primary outcome testing. Cerebral blood flow AUC increased immediately following exercise, regardless of APOE4 carrier status. In an exploratory regional analyses, we found that cerebral blood flow increased in hippocampal brain regions, while showing no change in cerebellum across both groups. Among high inter-individual variability, there were no significant changes in any of the 3 neurotrophic factors for either group immediately following exercise. Conclusions Our findings show that both APOE4 carriers and non-carriers show similar effects of exercise-induced increases in cerebral blood flow and neurotrophic response to acute aerobic exercise. Our results provide further evidence that acute exercise-induced increases in cerebral blood flow may be regional specific, and that exercise-induced neurotrophin release may show a differential effect in the aging cardiovascular system. Results from this study provide an initial characterization of the acute brain blood flow and neurotrophin responses to a bout of exercise in older adults with and without this known risk allele for cardiovascular disease and Alzheimer’s disease

Nontuberculous Mycobacteria–associated Lung Disease in Hospitalized Persons, United States, 1998–2005

This bacterium is an underappreciated cause of lung disease and infection rates appear to be increasing

A comparison of univariate, vector, bilinear autoregressive, and band power features for brain–computer interfaces

Selecting suitable feature types is crucial to obtain good overall brain–computer interface performance. Popular feature types include logarithmic band power (logBP), autoregressive (AR) parameters, time-domain parameters, and wavelet-based methods. In this study, we focused on different variants of AR models and compare performance with logBP features. In particular, we analyzed univariate, vector, and bilinear AR models. We used four-class motor imagery data from nine healthy users over two sessions. We used the first session to optimize parameters such as model order and frequency bands. We then evaluated optimized feature extraction methods on the unseen second session. We found that band power yields significantly higher classification accuracies than AR methods. However, we did not update the bias of the classifiers for the second session in our analysis procedure. When updating the bias at the beginning of a new session, we found no significant differences between all methods anymore. Furthermore, our results indicate that subject-specific optimization is not better than globally optimized parameters. The comparison within the AR methods showed that the vector model is significantly better than both univariate and bilinear variants. Finally, adding the prediction error variance to the feature space significantly improved classification results

Consensus on exercise reporting template (Cert): Modified delphi study

© 2016 American Physical Therapy Association. Background. Exercise interventions are often incompletely described in reports of clinical trials, hampering evaluation of results and replication and implementation into practice. Objective. The aim of this study was to develop a standardized method for reporting exercise programs in clinical trials: the Consensus on Exercise Reporting Template (CERT). Design and Methods. Using the EQUATOR Network’s methodological framework, 137 exercise experts were invited to participate in a Delphi consensus study. A list of 41 items was identified from a meta-epidemiologic study of 73 systematic reviews of exercise. For each item, participants indicated agreement on an 11-point rating scale. Consensus for item inclusion was defined a priori as greater than 70% agreement of respondents rating an item 7 or above. Three sequential rounds of anonymous online questionnaires and a Delphi workshop were used. Results. There were 57 (response rate=42%), 54 (response rate=95%), and 49 (response rate=91%) respondents to rounds 1 through 3, respectively, from 11 countries and a range of disciplines. In round 1, 2 items were excluded; 24 items reached consensus for inclusion (8 items accepted in original format), and 16 items were revised in response to participant suggestions. Of 14 items in round 2, 3 were excluded, 11 reached consensus for inclusion (4 items accepted in original format), and 7 were reworded. Sixteen items were included in round 3, and all items reached greater than 70% consensus for inclusion. Limitations. The views of included Delphi panelists may differ from those of experts who declined participation and may not fully represent the views of all exercise experts. Conclusions. The CERT, a 16-item checklist developed by an international panel of exercise experts, is designed to improve the reporting of exercise programs in all evaluative study designs and contains 7 categories: materials, provider, delivery, location, dosage, tailoring, and compliance. The CERT will encourage transparency, improve trial interpretation and replication, and facilitate implementation of effective exercise interventions into practice

Interventions for reducing sedentary behaviour in people with stroke

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To determine whether interventions primarily intended to reduce time spent in sedentary behaviour after stroke reduce sedentary time, and whether they modify cardiovascular risk, and reduce the risk of death or secondary vascular events. We will also include interventions intended to reduce the length of prolonged uninterrupted periods of sedentary behaviour (i.e. interventions to fragment or interrupt). Primary objectives To determine whether interventions to reduce or interrupt sedentary time influence: mortality; recurrent cerebrovascular or cardiovascular events. Secondary objectives To determine whether interventions to reduce or interrupt sedentary time influence: amount of sedentary time; cardiometabolic risk profile (e.g. glucose tolerance, arterial function, blood cholesterol and blood pressure); adverse events (in addition to recurrent events, for example falls). Other objectives In addition, we will as a scoping exercise, describe the range of all outcome measures reported in all trials. By definition, any included study interventions will fall within the umbrella of physical activity.Therefore, it may be that multiple plausible benefits could emerge that are common to other energy-expending interventions