2016 Summer Scholars learning research ropes at Brain Sciences Center
Posttraumatic Stress Disorderprojects, plus assisting Drs. Shikha Jain Goodwin and Adam Carpenter with their study of multiple sclerosis.Elsa Mattson (University of Minnesota/neuroscience minor) is interested in the neural mechanisms and gender differences in psychopathology.Lindsey Wanberg (Washington University, St. Louis/pre-med, biology) is also performing her own research on secondary traumatic stress.Kha Lor (University of St. Thomas/neuroscience major) has explored the computational and physical surface-induced collisions of polypeptides. Her main research project will be with Dr. Brian Engdahl, looking at
PTSDand Quality of Life as outcome variables. She will also be working under Drs. Lisa James and Jennifer Heath Mathison with the Brain Resilience Project and
Gulf War Illnessstudies.Michaela McGonigle (Macalester College/psychology major, biology minor with neuroscience emphasis) has studied facial expression processing in the human brain and measured the visual capacity of neurotypical adults in comparison to...
Overcoming Long-Term Variability in Local Field Potentials Using an Adaptive Decoder
permalinkIEEE Transactions on Biomedical Engineering - 2016-04-20Tadipatri VA, Tewfik AH, Pellizzer G10.1109/TBME.2016.2557070Long-term variability remains one of the major hurdles in using intracortical recordings like local field potentials for brain computer interfaces (BCI). Practical neural decoders need to overcome time instability of neural signals to estimate subject behavior accurately and faithfully over the long term. This paper presents a novel decoder that 1) characterizes each behavioral task (i.e., different movement directions under different force conditions) with multiple neural patterns and 2) adapts to the long-term variations in neural features by identifying the stable neural patterns. This adaptation can be performed in both an unsupervised and a semisupervised learning framework requiring minimal feedback from the user. To achieve generalization over time, the proposed decoder uses redundant sparse regression models that adapt to day-to-day variations in neural patterns. While this update requires no explicit feedback from the BCI user, any feedback (explicit or derived) to the BCI improves its performance. With this adaptive decoder, we...
Monkey Prefrontal Neurons Reflect Logical Operations for Cognitive Control in a Variant of the AX Continuous Performance Task (AX-CPT)
permalinkJournal of Neuroscience - 2016-04-06Blackman R, Crowe D, DeNicola A, Sakellaridi S, MacDonald III AW, Chafee M10.1523/JNEUROSCI.3578-15.2016Cognitive control is the ability to modify the behavioral response to a stimulus based on internal representations of goals or rules. We sought to characterize neural mechanisms in prefrontal cortex associated with cognitive control in a context that would maximize the potential for future translational relevance to human neuropsychiatric disease. To that end, we trained monkeys to perform a dot-pattern variant of the AX continuous performance task that is used to measure cognitive control impairment in patients with schizophrenia (MacDonald, 2008; Jones et al., 2010). Here we describe how information processing for cognitive control in this task is related to neural activity patterns in prefrontal cortex of monkeys, to advance our understanding of how behavioral flexibility is implemented by prefrontal neurons in general, and to model neural signals in the healthy brain that may be disrupted to produce cognitive control deficits in schizophrenia. We found that the neural representation of stimuli...
Researchers pinpoint circuits that drive Posttraumatic Stress Disorder flashbacks
permalinkCBC News - David Kattenburg - 2016-02-04From the article:
Studies could help people suffering from panic attacks, psychosis and obsessive-compulsive disorder."It's like sort of boxes opening up, and your brain just launches these things without you actually trying to stimulate them." That was how then-senator, and retired general, Romeo Dallaire described the flashbacks that bubble up in his head.Dallaire made the comments in a 2013 interview with the CBC's Sunday Edition, 20 years after the Rwandan genocide he tried to stop. He's far from alone in dealing with those type of unwelcome flashbacks. An estimated 10 per cent of Canadians struggle with depression, flashbacks and panic attacks as a result of post-traumatic stress disorder, orPTSD, according to the Canadian Mental Health Association. ...
Differential neural activity patterns for spatial relations in humans: a Magnetoencephalography study
permalinkExperimental Brain Research - 2016-02-01Scott NM, Leuthold A, Sera MD, Georgopoulos AP10.1007/s00221-015-4467-6Children learn the words for above-below relations earlier than for left-right relations, despite treating these equally well in a simple visual categorization task. Even as adults-conflicts in congruency, such as when a stimulus is depicted in a spatially incongruent manner with respect to salient global cues-can be challenging. Here we investigated the neural correlates of encoding and maintaining in working memory above-below and left-right relational planes in 12 adults using magnetoencephalography in order to discover whether above-below relations are represented by the brain differently than left-right relations. Adults performed perfectly on the task behaviorally, so any differences in neural activity were attributed to the stimuli's cognitive attributes. In comparing above-below to left-right relations during stimulus encoding, we found the greatest differences in neural activity in areas associated with space and movement. In comparing congruent to incongruent trials, we found the greatest differential activity in premotor areas. For both contrasts, brain areas...
Integrating Insults: Using Fault Tree Analysis to Guide Schizophrenia Research across Levels of Analysis
permalinkFrontiers in Human Neuroscience - 2016-01-06MacDonald III AW, Zick JL, Chafee M, Netoff TI10.3389/fnhum.2015.00698The grand challenges of schizophrenia research are linking the causes of the disorder to its symptoms and finding ways to overcome those symptoms. We argue that the field will be unable to address these challenges within psychiatry's standard neo-Kraepelinian (DSM) perspective. At the same time the current corrective, based in molecular genetics and cognitive neuroscience, is also likely to flounder due to its neglect for psychiatry's syndromal structure. We suggest adopting a new approach long used in reliability engineering, which also serves as a synthesis of these approaches. This approach, known as fault tree analysis, can be combined with extant neuroscientific data collection and computational modeling efforts to uncover the causal structures underlying the cognitive and affective failures in people with schizophrenia as well as other complex psychiatric phenomena. By making explicit how causes combine from basic faults to downstream failures, this approach makes affordances for: (1) causes that are neither...
The Exploration of Dietary Habits Associated with Healthy Brain Functioning Across the Lifespan
permalinkSociety for Neuroscience - 2016-01-01Mathison JH, James L, Hoover H, Georgopoulos A, Georgopoulos APThe Healthy Brain Project (HBP) is a unique study at the
Brain Sciences Centerthat integrates neuroimaging, genetics, cognitive, and lifestyle data in order to identify characteristics associated with healthy brain aging . Participants are cognitively healthy women veterans from ealty adulthood to advanced old age. Collecting such data from a healthy population could allow for more detailed identification of dietary habits associated with healthy brain function across the lifespan.
Reduced Human Leukocyte Antigen Protection in Gulf War Illness
permalinkEBioMedicine - 2016-01-01Georgopoulos AP, James L, Mahan M, Joseph J, Georgopoulos A, Engdahl B10.1016/j.ebiom.2015.11.037BackgroundGulf War Illness (
GWI) is a disease of unknown etiology with symptoms suggesting the involvement of an immune process. Here we tested the hypothesis that
Human Leukocyte Antigencomposition might differ between veterans with and without
GWI.MethodsWe identified 144 unique alleles of Class I and II
HLAgenes in 82 veterans (66 with and 16 without
GWI). We tested the hypothesis that a subset of
HLAalleles may classify veterans in their respective group using a stepwise linear discriminant analysis. In addition, each participant rated symptom severity in 6 domains according to established
GWIcriteria, and an overall symptom severity was calculated.FindingsWe found 6 Class II alleles that classified participants 84.1% correctly (13/16 control and 56/66
GWI). The number of copies of the 6 alleles was significantly higher in the control group, suggesting a protective role. This was supported by a significant negative dependence of overall symptom severity on the...
Please Repeat - Classification of 3D Reach Targets from Electroenephalographic Signals is Enhanced by Repetition
permalinkCurrent Research in Motor Control V - 2016-01-01Sosnik R, Tadipatri VA, Tewfik AH, Pellizzer GThe advent of high quality multi-channel EEG recording systems and the significant advance in the field of machine learning enabled decoding complex motion features, such as the direction of hand movement in real (Waldert et al. 2008) and imaginary conditions (Ofner and Muller-Putz 2015). These decoding algorithms usually use classifiers like linear discriminant analysis (LDA) and support vector machine (SVM) on signal features to decode classes of movements, while other algorithms such as multivariate regression (MVR) are used to decode hand movement trajectories (Rickert et al. 2005). Currently, the discrimination of actual or imagined pointing movements to different targets with the same limb is modest. This is due to the fact that these motor tasks activate essentially the same motor-related neural networks for all targets, thus, the discrimination between different actual or imagined movements has to rely more heavily on differences in temporal and spectral features of the neural activity rather...
Neural Network Decorrelation for Healthy Brain Aging: A Cross-sectional and Longitudinal Magnetoencephalography study
Multigenerational Legacies of Trauma: Modeling the What and How of Transmission
permalinkAmerican Journal of Orthopsychiatry - 2016-01-01Danieli Y, Norris FH, Engdahl B10.1037/ort0000145To operationalize the theory of Trauma and the Continuity of Self: A Multidimensional, Multidisciplinary, Integrative Framework (Danieli, 1998), we created a testable model using factors in Holocaust survivors' lives that may have affected their offspring's adaptation. A web-based sample of 422 adult children of survivors completed a 3-part inventory assessing multigenerational legacies of trauma. To explain the severity of the child's reparative adaptational impacts, we conducted hierarchical regression analyses (Phase 1) and path analyses (Phase 2). We hypothesized that these impacts followed largely from the (child-reported) intensities of parents' victim, numb, and fighter posttrauma adaptational styles. These styles, in turn, followed from family history and post-Holocaust family milieu. With all effects of family history and milieu on offspring specified as indirect (through parents' victim styles), the initial path model fit the data well with one exception: Broken generational linkages had direct as well as indirect effects. While survivors' Holocaust experiences-especially internment-had...
Blood Test Could Determine Who May Suffer from Gulf War Illness
Pathological personality traits modulate neural interactions
permalinkExperimental Brain Research - 2015-12-01James L, Engdahl B, Leuthold A, Krueger RF, Georgopoulos AP10.1007/s00221-015-4406-6The DSM\-5, includes an empirically supported dimensional model of personality pathology that is assessed via the Personality Inventory for the
Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition(PID-5). Here we used
MEG; 248 sensors) to evaluate resting-state neural network properties associated with the five primary
DSM-5maladaptive personality domains (negative affect, detachment, antagonism, disinhibition, and psychoticism) in 150 healthy veterans ("control" group) and 179 veterans with various psychiatric disorders ("psychopathology" group). Since a fundamental network property is the strength of functional connectivity among network elements, we used the absolute value of the pairwise correlation coefficient (aCC) between prewhitened
MEGsensor time series as a measure of neural functional connectivity and assessed its relations to the quantitative PID-5 scores in a linear regression model, where the log-transformed aCC was the dependent variable and individual PID scores, age, and gender were the independent variables. The partial regression coefficient (pRC)...
Neural mechanisms underlying the exploration of small city maps using magnetoencephalography
permalinkExperimental Brain Research - 2015-11-01Sakellaridi S, Christova P, Christopoulos V, Leuthold A, Peponis J, Georgopoulos AP10.1007/s00221-015-4387-5The neural mechanisms underlying spatial cognition in the context of exploring realistic city maps are unknown. We conducted a novel brain imaging study to address the question of whether and how features of special importance for map exploration are encoded in the brain to make a spatial decision. Subjects explored by eyes small city maps exemplifying five different street network types in order to locate a hypothetical City Hall, while neural activity was recorded continuously by 248
MEGsensors at high temporal resolution. Monitoring subjects' eye positions, we locally characterized the maps by computing three spatial parameters of the areas that were explored. We computed the number of street intersections, the total street length, and the regularity index in the circular areas of 6 degrees of visual angle radius centered on instantaneous eye positions. We tested the hypothesis that neural activity during exploration is associated with the spatial parameters and...
A Brain in a Dish
The Danieli Inventory of Multigenerational Legacies of Trauma, Part I: Survivors' posttrauma adaptational styles in their children's eyes
permalinkJournal of Psychiatric Research - 2015-09-01Danieli Y, Norris FH, Lindert J, Paisner V, Engdahl B, Richter J10.1016/j.jpsychires.2015.06.011A comprehensive valid behavioral measure for assessing multidimensional multigenerational impacts of massive trauma has been missing thus far. We describe the development of the Posttrauma Adaptational Styles questionnaire (Part I of the three-part Danieli Inventory of Multigenerational Legacies of Trauma), a self-report questionnaire of Holocaust survivors' children's perceptions of each parent and their own upbringing (60 items per parent). The items were based on literature and cognitive interviewing of 18 survivors' offspring. A web-based convenience sample survey was designed in English and Hebrew and completed by 482 adult children (M age = 59; 67% women) of Holocaust survivors. Exploratory factor analyses were conducted by using maximum likelihood extraction with Geomin rotation to examine the factor structure of the original 70 items for each parent. Conducted hierarchically, the analysis yielded three higher-order factors reflecting intensities of victim, numb, and fighter styles. The 30-item Victim Style Scale (α = .92-.93) and 18-item Numb...
Evaluating the dimensionality of Posttraumatic Stress Disorder in a sample of Operation Iraqi Freedom/Operation Enduring Freedom - Afghanistan veterans
permalinkPsychological Trauma: Theory, Research, Practice, and Policy - 2015-09-01Frankfurt S, Anders S, James L, Engdahl B, Winskowski AM10.1037/tra0000012Both categorical and dimensional models of mental disorders, including
PTSD, are useful for diagnostic and heuristic purposes; however, few empirical studies have compared categorical and dimensional models of
PTSDside-by-side or compared these models to a hybrid (dimensional and categorical) model. In the present study, the dimensionality of
PTSDwas examined by fitting latent profile analytic, confirmatory factor analytic, and factor mixture models in 271
Operation Iraqi Freedom/Operation Enduring Freedom veterans 6 months after return from deployment. Latent profile analysis was used to identify subgroups of individuals with similar
PTSDsymptom profiles and predictors of subgroup membership, confirmatory factor analysis was used to identify the underlying continuous structure of
PTSDin this sample, and factor mixture modeling was used to test whether a hybrid categorical and continuous model of
PTSDbest fit our sample. A factor mixture model consisting of a 4-factor dysphoria model of
Diagnosis of Posttraumatic Stress Disorder based on correlations of prewhitened Functional Magnetic Resonance Imaging data: outcomes and areas involved
permalinkExperimental Brain Research - 2015-09-01Christova P, James L, Engdahl B, Lewis S, Georgopoulos AP10.1007/s00221-015-4339-0Successful diagnosis of
PTSDhas been achieved using neural correlations from prewhitened magnetoencephalographic (
MEG) time series (Georgopoulos et al. in J Neural Eng 7:16011, 2010. doi:10.1088/1741-2560/7/1/016011; James et al. 2015). Here, we show that highly successful classification of
PTSDand control subjects can be obtained using neural correlations from prewhitened resting-state
Functional Magnetic Resonance Imagingdata. All but one
PTSD(14/15; sensitivity = 93.3 %) and all but one control (20/21; specificity = 95.2 %) subjects were correctly classified using 15 out of 2701 possible correlations between 74 brain areas. In contrast, correlations of the same but non-prewhitened data yielded chance-level classifications. We conclude that, if properly processed,
fMRIhas the prospect of aiding significantly in
PTSDdiagnosis. Twenty-five brain areas were most prominently involved in correct subject classification, including areas from all cortical lobes and the left pallidum.
POWs, Posttraumatic Stress Disorder and Coping
PTSDand coping mechanisms with Dr. Brian Engdahl from the Minneapolis VA.
Coding of movements in the motor cortex