[Standing- and gait therapy in adult patients after stroke: overview of reviews]

BACKGROUND AND OBJECTIVES

The number of strokes will increase within the next years. Therefore, more people will have deficits in standing and ambulation. In the context of rehabilitation there are a large number of different interventions that can improve these restrictions. This paper provides an overview about possible interventions and their evidence.

METHODS

Systematic Reviews of the Cochrane Collaboration were searched and summarized in an overview of reviews.

MAIN RESULTS

Some of the interventions that investigated different methods of standing- and gait training showed positive eff ects in walking capacity, gait speed, dynamic standing balance, stance symmetry, balance self-efficacy and gait in dependence. Circuit class therapy and overground physical therapy gait training showed the best eff ects of the investigated interventions. Both interventions improved walking capacity, gait speed, balance and gait independence.

CONCLUSION

The investigated interventions showed positive eff ects in standing and ambulation in patients after stroke. The interventions should be goal-oriented, task-specific and repetitive.

A functional variant in the neuropeptide S receptor 1 gene moderates the influence of urban upbringing on stress processing in the amygdala

We have previously shown that urban upbringing and city living were associated with stress-induced activity in the amygdala and the perigenual anterior cingulate cortex (pACC). This finding might link the epidemiological risk factor "urbanicity" to neurobiological mechanisms of psychiatric disorders. However, given the heritability of stress-related phenotypes, it appears likely that genetic factors can modulate the effect of urbanicity on social stress processing. In the present exploratory study, we investigated if a functional sequence variation in the neuropeptide S receptor gene (NPSR1 rs324981) is associated with brain activation patterns under acute psychosocial stress and if it modulates the link between urbanicity and central stress processing. In animals, neuropeptide S has strong anxiolytic effects and it induces hypothalamus-pituitary-adrenal (HPA) axis activation. In humans, rs324981 was found to be associated with anxiety and stress-related phenotypes. Forty-two subjects were exposed to a psychosocial stress task for scanner environments (ScanSTRESS). While no main effect of rs324981 on amygdala and pACC activity was detected, we found a distinct interaction between rs324981 and urban upbringing modulating right amygdala responses. Moreover, right amygdala responses were significantly higher in subjects who also showed a salivary cortisol response to the stress exposure. The present finding of a gene × environment interaction further supports the view that the brain NPS system is involved in central stress regulation. This study provides first evidence for the assumption that a NPSR1 variant modulates brain activation under stress, interacting with the environmental risk factor urban upbringing.

Neuroimaging evidence for a role of neural social stress processing in ethnic minority-associated environmental risk

IMPORTANCE

Relative risk for the brain disorder schizophrenia is more than doubled in ethnic minorities, an effect that is evident across countries and linked to socially relevant cues such as skin color, making ethnic minority status a well-established social environmental risk factor. Pathoepidemiological models propose a role for chronic social stress and perceived discrimination for mental health risk in ethnic minorities, but the neurobiology is unexplored.

OBJECTIVE

To study neural social stress processing, using functional magnetic resonance imaging, and associations with perceived discrimination in ethnic minority individuals.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional design in a university setting using 3 validated paradigms to challenge neural social stress processing and, to probe for specificity, emotional and cognitive brain functions. Healthy participants included those with German lineage (n = 40) and those of ethnic minority (n = 40) from different ethnic backgrounds matched for sociodemographic, psychological, and task performance characteristics. Control comparisons examined stress processing with matched ethnic background of investigators (23 Turkish vs 23 German participants) and basic emotional and cognitive tasks (24 Turkish vs 24 German participants).

MAIN OUTCOMES AND MEASURES

Blood oxygenation level-dependent response, functional connectivity, and psychological and physiological measures.

RESULTS

There were significant increases in heart rate (P < .001), subjective emotional response (self-related emotions, P < .001; subjective anxiety, P = .006), and salivary cortisol level (P = .004) during functional magnetic resonance imaging stress induction. Ethnic minority individuals had significantly higher perceived chronic stress levels (P = .02) as well as increased activation (family-wise error-corrected [FWE] P = .005, region of interest corrected) and increased functional connectivity (PFWE = .01, region of interest corrected) of perigenual anterior cingulate cortex (ACC). The effects were specific to stress and not explained by a social distance effect. Ethnic minority individuals had significant correlations between perceived group discrimination and activation in perigenual ACC (PFWE = .001, region of interest corrected) and ventral striatum (PFWE = .02, whole brain corrected) and mediation of the relationship between perceived discrimination and perigenual ACC-dorsal ACC connectivity by chronic stress (P < .05).

CONCLUSIONS AND RELEVANCE

Epidemiologists proposed a causal role of social-evaluative stress, but the neural processes that could mediate this susceptibility effect were unknown. Our data demonstrate the potential of investigating associations from epidemiology with neuroimaging, suggest brain effects of social marginalization, and highlight a neural system in which environmental and genetic risk factors for mental illness may converge.

Striatal response to reward anticipation: evidence for a systems-level intermediate phenotype for schizophrenia

IMPORTANCE

Attenuated ventral striatal response during reward anticipation is a core feature of schizophrenia that is seen in prodromal, drug-naive, and chronic schizophrenic patients. Schizophrenia is highly heritable, raising the possibility that this phenotype is related to the genetic risk for the disorder.

OBJECTIVE

To examine a large sample of healthy first-degree relatives of schizophrenic patients and compare their neural responses to reward anticipation with those of carefully matched controls without a family psychiatric history. To further support the utility of this phenotype, we studied its test-retest reliability, its potential brain structural contributions, and the effects of a protective missense variant in neuregulin 1 (NRG1) linked to schizophrenia by meta-analysis (ie, rs10503929).

DESIGN, SETTING, AND PARTICIPANTS

Examination of a well-established monetary reward anticipation paradigm during functional magnetic resonance imaging at a university hospital; voxel-based morphometry; test-retest reliability analysis of striatal activations in an independent sample of 25 healthy participants scanned twice with the same task; and imaging genetics analysis of the control group. A total of 54 healthy first-degree relatives of schizophrenic patients and 80 controls matched for demographic, psychological, clinical, and task performance characteristics were studied.

MAIN OUTCOMES AND MEASURES

Blood oxygen level-dependent response during reward anticipation, analysis of intraclass correlations of functional contrasts, and associations between striatal gray matter volume and NRG1 genotype.

RESULTS

Compared with controls, healthy first-degree relatives showed a highly significant decrease in ventral striatal activation during reward anticipation (familywise error-corrected P < .03 for multiple comparisons across the whole brain). Supplemental analyses confirmed that the identified systems-level functional phenotype is reliable (with intraclass correlation coefficients of 0.59-0.73), independent of local gray matter volume (with no corresponding group differences and no correlation to function, and with all uncorrected P values >.05), and affected by the NRG1 genotype (higher striatal responses in controls with the protective rs10503929 C allele; familywise error-corrected P < .03 for ventral striatal response).

CONCLUSIONS AND RELEVANCE

Healthy first-degree relatives of schizophrenic patients show altered striatal activation during reward anticipation in a directionality and localization consistent with prior patient findings. This provides evidence for a functional neural system mechanism related to familial risk. The phenotype can be assessed reliably, is independent of alterations in striatal structure, and is influenced by a schizophrenia candidate gene variant in NRG1. These data encourage us to further investigate the genetic and molecular contributions to this phenotype.

Quantifying inter-individual anatomical variability in the subcortex using 7 T structural MRI

Functional magnetic resonance imaging (MRI) data are usually registered into standard anatomical space. However, standard atlases, such as LPBA40, the Harvard-Oxford atlas, FreeSurfer, and the Jülich cytoarchitectonic maps all lack important detailed information about small subcortical structures like the substantia nigra and subthalamic nucleus. Here we introduce a new subcortical probabilistic atlas based on ultra-high resolution in-vivo anatomical imaging from 7 T MRI. The atlas includes six important but elusive subcortical nuclei: the striatum, the globus pallidus internal and external segment (GPi/e), the subthalamic nucleus, the substantia nigra, and the red nucleus. With a sample of 30 young subjects and carefully cross-validated delineation protocols, our atlas is able to capture the anatomical variability within healthy populations for each of the included structures at an unprecedented level of detail. All the generated probabilistic atlases are registered to MNI standard space and are publicly available.

Paramagnetic squeezing of QCD matter

We determine the magnetization of quantum chromodynamics for several temperatures around and above the transition between the hadronic and the quark-gluon phases of strongly interacting matter. We obtain a paramagnetic response that increases in strength with the temperature. We argue that due to this paramagnetism, chunks of quark-gluon plasma produced in noncentral heavy ion collisions should become squeezed perpendicular to the magnetic field. This anisotropy will then contribute to the elliptic flow v2 observed in such collisions, in addition to the pressure gradient that is usually taken into account. We present a simple estimate for the magnitude of this new effect and a rough comparison to the effect due to the initial collision geometry. We conclude that the paramagnetic effect might have a significant impact on the value of v2.

[Differentiated antiplatelet therapy for acute coronary syndromes]

Dual antiplatelet therapy is the cornerstone of maintenance medication following invasive treatment of patients with acute coronary syndromes (ST elevation myocardial infarction, non-ST elevation myocardial infarction, unstable angina). Over the last decade, P2Y12 inhibition in addition to low-dose acetylsalicylic acid has been intensively debated. The debate was enriched by the results of the large phase III clinical trials for prasugrel (TRITON) and ticagrelor (PLATO) compared to clopidogrel in patients with acute coronary syndromes. This article summarizes the critical details und subanalyses of both study programmes and highlights on clinical decision making when using the three P2Y12 blockers in acute coronary syndromes. A special focus is on higher risk patients such as those with ST elevation myocardial infarction and those with coexisting diabetes, but also on minimizing relevant bleedings, which are common during more intense platelet inhibition.

Inhomogeneous thermalization in strongly coupled field theories

To describe theoretically the creation and evolution of the quark-gluon plasma, one typically employs three ingredients: a model for the initial state, nonhydrodynamic early time evolution, and hydrodynamics. In this Letter we study the nonhydrodynamic early time evolution using the AdS/CFT correspondence in the presence of inhomogeneities. We find that the AdS description of the early time evolution is well matched by free streaming. Near the end of the early time interval where our analytic computations are reliable, the stress tensor agrees with the second order hydrodynamic stress tensor computed from the local energy density and fluid velocity. Our techniques may also be useful for the study of far-from-equilibrium strongly coupled systems in other areas of physics.

Test-retest reliability of fMRI-based graph theoretical properties during working memory, emotion processing, and resting state

The investigation of the brain connectome with functional magnetic resonance imaging (fMRI) and graph theory analyses has recently gained much popularity, but little is known about the robustness of these properties, in particular those derived from active fMRI tasks. Here, we studied the test-retest reliability of brain graphs calculated from 26 healthy participants with three established fMRI experiments (n-back working memory, emotional face-matching, resting state) and two parcellation schemes for node definition (AAL atlas, functional atlas proposed by Power et al.). We compared the intra-class correlation coefficients (ICCs) of five different data processing strategies and demonstrated a superior reliability of task-regression methods with condition-specific regressors. The between-task comparison revealed significantly higher ICCs for resting state relative to the active tasks, and a superiority of the n-back task relative to the face-matching task for global and local network properties. While the mean ICCs were typically lower for the active tasks, overall fair to good reliabilities were detected for global and local connectivity properties, and for the n-back task with both atlases, smallworldness. For all three tasks and atlases, low mean ICCs were seen for the local network properties. However, node-specific good reliabilities were detected for node degree in regions known to be critical for the challenged functions (resting-state: default-mode network nodes, n-back: fronto-parietal nodes, face-matching: limbic nodes). Between-atlas comparison demonstrated significantly higher reliabilities for the functional parcellations for global and local network properties. Our findings can inform the choice of processing strategies, brain atlases and outcome properties for fMRI studies using active tasks, graph theory methods, and within-subject designs, in particular future pharmaco-fMRI studies.

[Subgroup-specific therapy of low back pain: description and validity of two classification systems]

BACKGROUND

In spite of profound advances in the diagnosis and therapy, low back pain (LBP) remains one of the main challenges for health systems in western industrialized countries. Clinical trials and meta-analyses typically show heterogeneous evidence and small effect sizes. One explanation for this phenomenon is the heterogeneous nature of the population of patients with LBP, not adequately considered in clinical practice and research. Recent studies and one meta-analysis show that therapy which is specifically directed at well defined subgroups leads to improved effectiveness of interventions, especially for non-surgical interventions such as manual therapy or physiotherapy.

AIM

This article aims to describe the process of classification and to critically evaluate the underlying evidence.

METHODS

Two validated and commonly used classification systems were selected and their reliability and validity were critically appraised.

RESULTS

The treatment-based classification system was primarily developed and validated for patients with acute LBP. Based on prognostic factors and clinical prediction rules, patients are classified into one of four treatment based categories: traction, manipulation, specific exercises and stabilization. The movement and motor control impairment classification system is based on movement-related, cognitive and psychosocial factors and was developed for patients with chronic LBP. Maladaptive movement and motor control impairments are considered as underlying mechanisms. Three broad subgroups are proposed: firstly, a group with specific pathologies, such as spinal stenosis or disc prolapse with radiculopathy, secondly a group with dominant psychosocial factors and thirdly a group with maladaptive motor control patterns that drive the disorder with either movement impairments or motor control impairments.

CONCLUSION

The reliability of the described classification systems is moderate to good, aspects of validity have been shown. Their implementation in clinical practice seems recommendable.

Investigation of spoilage in saveloy samples inoculated with four potential spoilage bacteria

Sliced saveloy samples were inoculated with monocultures of four potential spoilage bacteria and studied during a four week storage period. The objective was to investigate the resulting changes in the composition of Volatile Organic Compounds (VOCs) and the sensory quality of the product. Based on the sensory scores and the VOC composition Brochothrix thermosphacta, Chryseomonas luteola and Carnobacterium maltaromaticum were found to have a high spoilage potential in saveloy samples subjected to consumer simulated storage during the fourth week. Inoculation with Leuconostoc carnosum only resulted in a low level of spoilage. The sensory changes in the saveloy samples were modeled based on the VOC composition using Partial Least Squares Regression. The changes in the six sensory descriptors were closely related to the amount of diacetyl, acetoin, 2- and 3-methylbutanol, 2- and 3-methylbutanal and 2-methylpropanol found in the samples. These compounds are therefore potentially important for the shelf-life of sliced saveloy.

Neural mechanisms of selective exposure: an EEG study on the processing of decision-consistent and inconsistent information

Decision makers tend to prefer decision-consistent information and/or neglect decision-inconsistent information (selective exposure). In the present EEG study the neural mechanisms of the classic selective exposure effect were examined by investigating oscillatory brain responses to consistent vs. inconsistent information. Twenty participants made an economic decision and subsequently were exposed to 45 consistent and 45 inconsistent images concerning their decision. EEG was recorded from 31 electrodes and differences between oscillatory brain responses towards consistent and inconsistent information were examined. The main result was an increase of induced theta power (5-8Hz, 0-0.7s) in the consistent compared to the inconsistent condition at right temporo-parietal electrodes, as well as a corresponding increase of evoked theta power at frontal electrodes. Since theta oscillations are often observed during memory formation, we conclude that decision-consistent information triggers memory formation, whereas decision-inconsistent information seems not to do so. This finding supports the classic motivational perspective of Leon Festinger on the selective exposure effect.

[Managing psychiatric side effects of antiviral therapy in chronic hepatitis C]

The efficacy of antiviral therapy in patients with chronic hepatitis C virus (HCV) infection has largely improved over the last years. Rates of long-term therapy success (sustained virological response, SVR) clearly exceed 50% in the population of all antivirally treated HCV patients, even when including the less favourable virus genotypes 1 and 4. From recent research, it is well-known that adherence to current standard combination therapy (peginterferon alfa plus ribavirin) is crucial for the achievement of sustained response. Psychiatric adverse events, however, are subjectively very burdening and are among the most frequent reasons for premature discontinuation of antiviral therapy in HCV patients and therefore endanger therapy success. Therefore, effective side effect management regarding this branch of symptoms (e.g. depression, anger-hostility, anxiety) is to be considered crucial for the achievement of SVR. This review presents a current overview of the most relevant IFN-associated psychiatric side effects in antivirally treated patients with chronic hepatitis C infection. Moreover, various strategies for the management of these undesired conditions are reported: In particular, we address the issues of diagnostics and pretherapeutic screening for risk factors for the subsequent development of IFN-associated psychiatric symptoms. Moreover, we provide an overview of suitable instruments for the psychiatric monitoring of patients on antiviral therapy. We further discuss appropriate treatment strategies (e.g. prophylactic medication vs. medication only after the occurrence of symptoms) as well as indications for immediate therapy discontinuation due to serious psychiatric adverse events. In many cases, premature therapy discontinuation can be prevented by individual and adequate side effect management, provided that it is started in a timely manner. The continuing clinical relevance of psychiatric side effect management in this context is further backed up by the fact that also novel treatment strategies comprising protease or polymerase inhibitors will still include pegylated interferon alfa and ribavirin.

How accurate is pulse rate variability as an estimate of heart rate variability? A review on studies comparing photoplethysmographic technology with an electrocardiogram

BACKGROUND

The usefulness of heart rate variability (HRV) as a clinical research and diagnostic tool has been verified in numerous studies. The gold standard technique comprises analyzing time series of RR intervals from an electrocardiographic signal. However, some authors have used pulse cycle intervals instead of RR intervals, as they can be determined from a pulse wave (e.g. a photoplethysmographic) signal. This option is often called pulse rate variability (PRV), and utilizing it could expand the serviceability of pulse oximeters or simplify ambulatory monitoring of HRV.

METHODS

We review studies investigating the accuracy of PRV as an estimate of HRV, regardless of the underlying technology (photoplethysmography, continuous blood pressure monitoring or Finapresi, impedance plethysmography).

RESULTS/CONCLUSIONS

Results speak in favor of sufficient accuracy when subjects are at rest, although many studies suggest that short-term variability is somewhat overestimated by PRV, which reflects coupling effects between respiration and the cardiovascular system. Physical activity and some mental stressors seem to impair the agreement of PRV and HRV, often to an inacceptable extent. Findings regarding the position of the sensor or the detection algorithm are not conclusive. Generally, quantitative conclusions are impeded by the fact that results of different studies are mostly incommensurable due to diverse experimental settings and/or methods of analysis.

Exposure therapy leads to enhanced late frontal positivity in 8- to 13-year-old spider phobic girls

Neurobiological studies have demonstrated that psychotherapy is able to alter brain function in adults, however little exists on this topic with respect to children. This waiting-list controlled investigation focused on therapy-related changes of the P300 and the late positive potential (LPP) in 8- to 13-year-old spider phobic girls. Thirty-two patients were presented with phobia-relevant, generally disgust-inducing, fear-inducing, and affectively neutral pictures while an electroencephalogram was recorded. Participants received one session of up to 4h of cognitive-behavioral exposure therapy. Treated children showed enhanced amplitudes of the LPP at frontal sites in response to spider pictures. This result is interpreted to reflect an improvement in controlled attentional engagement and is in line with already existing data for adult females. Moreover, the girls showed a therapy-specific reduction in overall disgust proneness, as well as in experienced arousal and disgust when viewing disgust pictures. Thus, exposure therapy seems to have broad effects in children.

Threat engagement, disengagement, and sensitivity bias in worry-prone individuals as measured by an emotional go/no-go task

BACKGROUND AND OBJECTIVES

The goal of the present study was to investigate a threat engagement, disengagement, and sensitivity bias in individuals suffering from pathological worry.

METHODS

Twenty participants high in worry proneness and 16 control participants low in worry proneness completed an emotional go/no-go task with worry-related threat words and neutral words.

RESULTS

Shorter reaction times (i.e., threat engagement bias), smaller omission error rates (i.e., threat sensitivity bias), and larger commission error rates (i.e., threat disengagement bias) emerged only in the high worry group when worry-related words constituted the go-stimuli and neutral words the no-go stimuli. Also, smaller omission error rates as well as larger commission error rates were observed in the high worry group relative to the low worry group when worry-related go stimuli and neutral no-go stimuli were used.

LIMITATIONS

The obtained results await further replication within a generalized anxiety disorder sample. Also, further samples should include men as well.

CONCLUSIONS

Our data suggest that worry-prone individuals are threat-sensitive, engage more rapidly with aversion, and disengage harder.

Emotion recognition and experience in Huntington disease: a voxel-based morphometry study

BACKGROUND

The neuroanatomic basis of affective processing deficits in Huntington disease is insufficiently understood. We investigated whether Huntington disease-related deficits in emotion recognition and experience are associated with specific changes in grey matter volume.

METHOD

We assessed grey matter volume in symptomatic patients with Huntington disease and healthy controls using voxel-based morphometry, and we correlated regional grey matter volume with participants' affective ratings.

RESULTS

We enrolled 18 patients with Huntington disease and 18 healthy controls in our study. Patients with Huntington disease showed normal affective experience but impaired recognition of negative emotions (disgust, anger, sadness). The patients perceived the emotions as less intense and made more classification errors than controls. These deficits were correlated with regional atrophy in emotion-relevant areas (insula, orbitofrontal cortex) and in memory-relevant areas (dorsolateral prefrontal cortex, hippocampus).

LIMITATIONS

Our study was limited by the small sample size and the resulting modest statistical power relative to the number of tests.

CONCLUSION

Our study sheds new light on the importance of a cognitive-affective brain circuit involved in the affect recognition impairment in patients with Huntington disease.

Emotion recognition and experience in Huntington's disease: is there a differential impairment?

Findings on affective processing deficits in Huntington's disease (HD) have been inconsistent. It is still not clear whether HD patients are afflicted by specific deficits in emotion recognition and experience. We tested 28 symptomatic HD patients and presented them with pictures depicting facial expressions of emotions (Karolinska-Set) and with affective scenes (International Affective Picture System; IAPS). The faces were judged according to the displayed intensity of six basic emotions, whereas the scenes received intensity ratings for the elicited emotions in the viewer. Patients' responses were compared with those of 28 healthy controls. HD patients gave lower intensity ratings for facial expressions of anger, disgust and surprise than controls. Patients' recognition deficits were associated with reduced functional capacity, such as problems with social interactions. Moreover, their classification accuracy was reduced for angry, disgusted, sad and surprised faces. When judging affective scenes for the elicitation of happiness, disgust and fear, HD patients had a tendency to estimate them as more intense than controls. This finding points to a differential impairment in emotion recognition and emotion experience in HD. We found no significant correlations between emotion experience/recognition ratings and CAG repeats, symptom duration and UHDRS Motor Assessment in the patient group.

Auditory symptom provocation in dental phobia: a near-infrared spectroscopy study

The act of drilling a tooth belongs to the most feared situations of patients suffering from dental phobia. We presented 25 female patients and 24 nonphobic women with the sound of a dental drill, pleasant and neutral sounds. Brain activation was recorded via near infrared spectroscopy in fronto-parietal and premotor areas. The groups differed in supplementary motor area (SMA) recruitment. Relative to controls, the phobics displayed increased oxy hemoglobin while presented with the phobia-relevant sound, but showed comparable activation in the other conditions. As the SMA is engaged in the preparation of motor actions, the increased response in patients might mirror the priming of flight behavior during exposure. We found no indication of an emotional modulation of parietal and dorsomedial prefrontal cortex activation.

Disconnecting the yin and yang relation of epidermal growth factor receptor (EGFR)-mediated delivery: a fully synthetic, EGFR-targeted gene transfer system avoiding receptor activation

The epidermal growth factor receptor (EGFR) is upregulated within a high percentage of solid tumors and hence is an attractive target for tumor-targeted therapies including gene therapy. The natural EGFR ligand epidermal growth factor (EGF) has been used for this purpose, despite the risk of mitogenic effects due to EGFR activation. We have developed a fully synthetic, EGFR-targeted gene delivery system based on PEGylated linear polyethylenimine (LPEI), allowing evaluation of different EGFR-binding peptides in terms of transfection efficiency and EGFR activation. Peptide sequences directly derived from the human EGF molecule enhanced transfection efficiency with concomitant EGFR activation. Only the EGFR-binding peptide GE11, which has been identified by phage display technique, showed specific enhancement of transfection on EGFR-overexpressing tumor cells including glioblastoma and hepatoma, but without EGFR activation. EGFR targeting led to high levels of cell association of fluorescently labeled polyplexes after only 30 min of incubation. EGF pretreatment of cells induced enhanced cellular internalization of all polyplex types tested, pointing at generally enhanced macropinocytosis. EGF polyplexes diminished cell surface expression of EGFR for up to 4 hr, whereas GE11 polyplexes did not. In a clinically relevant orthotopic prostate cancer model, intratumorally injected GE11 polyplexes were superior in inducing transgene expression when compared with untargeted polyplexes.

Localized gray matter volume abnormalities in generalized anxiety disorder

Generalized anxiety disorder (GAD) is characterized by excessive and persistent worrying. Neural substrates of this disorder are insufficiently understood, which relates to functional as well as to structural brain abnormalities. Especially, findings on the neuroanatomy of GAD have been inconsistent and were predominantly derived from pediatric samples. Therefore, we studied adult patients. Thirty-one women (16 patients with GAD and 15 healthy control participants) underwent structural MRI scanning. Gray matter volumes for specific brain regions involved in worrying, anticipatory anxiety, and emotion regulation were analyzed by means of voxel-based morphometry. Relative to controls, patients with GAD had larger volumes of the amygdala and the dorsomedial prefrontal cortex (DMPFC). Moreover, patients' self-reports on symptom severity were positively correlated with volumes of the DMPFC and the anterior cingulate cortex. Patients with GAD show localized gray matter volume differences in brain regions associated with anticipatory anxiety and emotion regulation. This abnormality may represent either a predisposition for GAD or a consequence of disorder-specific behavior, such as chronic worrying. This issue should be addressed in future MRI studies.

Thermalization of strongly coupled field theories

Using the holographic mapping to a gravity dual, we calculate 2-point functions, Wilson loops, and entanglement entropy in strongly coupled field theories in d=2, 3, and 4 to probe the scale dependence of thermalization following a sudden injection of energy. For homogeneous initial conditions, the entanglement entropy thermalizes slowest and sets a time scale for equilibration that saturates a causality bound. The growth rate of entanglement entropy density is nearly volume-independent for small volumes but slows for larger volumes. In this setting, the UV thermalizes first.

Source localization of late electrocortical positivity during symptom provocation in spider phobia: an sLORETA study

This symptom provocation study on spider phobia investigated sources of late event-related potentials (ERPs) using sLORETA (standardized low resolution brain electromagnetic tomography). Twenty-five phobic female patients and 20 non-phobic controls were confronted with phobia-relevant, generally fear-inducing, disgust-inducing and affectively neutral pictures while an electroencephalogram was recorded. Mean amplitudes of ERPs were extracted in the time windows 340-500 ms (P300) and 550-770 ms (late positive potential, LPP). Phobics showed enhanced P300 and LPP amplitudes in response to spider pictures relative to controls. Sources were mainly located in areas engaged in visuo-attentional processing (occipital and parietal regions, ventral visual pathway). Moreover, there were sources in areas which are crucial for emotional processing and the representations of aversive bodily states (cingulate cortex, insula). Further sources were located in premotor areas reflecting the priming of flight behaviour. Our findings are in good accordance with existing brain imaging studies and underline that source localization is a useful alternative for identifying phobia-relevant cortical regions.

Affective perception and imagery: A NIRS study

The activation of cortical attention networks during affective picture processing has been extensively studied, whereas little is known about affective imagery. It is still unclear whether differences in emotional stimulus content are able to modulate visual cortex activation during imagery. Moreover, individual differences in emotional reactivity and imagery ability have not been investigated. The aim of this experiment was to examine these processes by means of near-infrared spectroscopy (NIRS). Thirty-five healthy adults were instructed to look at affective (disgust and happy) and neutral pictures and afterwards visualize them during multi-channel NIRS recording. Our main results indicated a differential involvement of parietal and occipital areas in the perception and imagery of affective pictures. In general, picture perception provoked increased oxygenated hemoglobin in occipital regions, whereas imagery was associated with an increase in parietal areas. Emotional content modulated activation of the left occipital cortex during both picture perception and imagery. Affective pictures (disgust and happy) provoked greater activation compared to neutral ones. Additionally, the self-rated imagery ability of the participants was positively correlated with their occipital activation during affective imagery. Thus, occipital activation might be crucial for the quality of imagery. In contrast, all correlations with emotional traits (e.g. trait disgust) and oxygenation were nonsignificant, which might be due to the fact that those personality factors predominantly modulate the activation of subcortical limbic structures which are not accessible with NIRS.

Outcomes differ between subgroups of patients with low back and leg pain following neural manual therapy: a prospective cohort study

The objective is to determine if pain and disability outcomes of patients treated with neural mobilisation differ for sub-classifications of low back and leg pain (LB&LP). Radiating leg pain is a poor prognostic factor for recovery in patients with LBP. To improve outcome, a new pathomechanism-based classification system was proposed: neuropathic sensitization (NS), denervation (D), peripheral nerve sensitization (PNS) and musculoskeletal (M). Seventy-seven patients with unilateral LB&LP were recruited. Following classification, all subjects were treated seven times with neural mobilisation techniques. A successful outcome was defined as achieving a minimal clinically important change in pain intensity (11-point numerical rating scale), physical function (Roland Morris disability questionnaire) and global perceived change (7-point Likert scale: from 1 = "completely recovered" to 7 = "worse than ever"). The proportion of responders was significantly greater in PNS (55.6%) than the other three groups (NS 10%; D 14.3% and M10%). After adjusting for baseline differences, mean magnitude of improvement of the outcome measures were significantly greater in PNS compared to the other groups. Patients classified as PNS have a more favourable prognosis following neural mobilisation compared to the other groups.

Insulin and hippocampus activation in response to images of high-calorie food in normal weight and obese adolescents

Responsiveness to food cues, especially those associated with high-calorie nutrients may be a factor underlying obesity. An increased motivational potency of foods appears to be mediated in part by the hippocampus. To clarify this, we investigated by means of 3-T magnetic resonance imaging (MRI) the activation of the hippocampus and associated brain structures in response to pictures of high-calorie and low-calorie foods in 12 obese and 12 normal-weight adolescents. To investigate the relationship between neuronal activation patterns (e.g., hippocampus) to the caloric content of food images and plasma insulin levels, we performed a multiple regression analysis. Interestingly, a significant positive correlation between fasting plasma levels of insulin, waist circumference, and right hippocampal activation was seen after stimulation with high-caloric food images. BMI values did not correlate significantly with the hippocampal activation. On the other hand, we found a significant negative correlation in response to high-caloric food images and the plasma levels of insulin in the medial right gyrus frontalis superior and in the left thalamus. In summary, our data show that insulin is importantly involved in the central regulation of food intake. The significant positive relationship between hippocampal activation after stimulation with high-caloric food images, plasma insulin levels, and waist circumference suggests a permissive role of insulin signaling pathways in the hippocampal control of eating behavior. Interestingly, only the waist circumference, as a main indicator of abdominal obesity, correlated significantly with the hippocampal activation patterns, and not the BMI.

Observation of the naive-T-odd Sivers effect in deep-inelastic scattering

Azimuthal single-spin asymmetries of leptoproduced pions and charged kaons were measured on a transversely polarized hydrogen target. Evidence for a naive-T-odd, transverse-momentum-dependent parton distribution function is deduced from nonvanishing Sivers effects for pi(+), pi(0), and K(+/-), as well as in the difference of the pi(+) and pi(-) cross sections.

An event-related potential study on exposure therapy for patients suffering from spider phobia

The present event-related potential (ERP) study investigated electrocortical changes related to cognitive behavior therapy (CBT) in spider phobic females. Forty-five patients and twenty non-phobic women were presented with phobia-relevant, generally fear-inducing, disgust-inducing and affectively neutral pictures in a first EEG session. Phobic patients were randomly assigned to either a therapy (TG) or a waiting-list (WG) group. EEG measurement was repeated after CBT or a waiting period. ERPs were extracted in the time windows 340-500ms (P300), 550-770ms (late positive potential (LPP), early LPP) and 800-1500ms (late LPP). Relative to controls, untreated phobics showed enhanced amplitudes of P300 and early LPP in response to spider pictures. This most likely reflects the emotional significance of the phobic stimulus, which automatically draws attention. The therapy effect consisted of a significant enhancement of late LPP amplitudes in response to spider pictures. Results are discussed in terms of reduced attentional avoidance.

In search of specificity: functional MRI in the study of emotional experience

The growing availability of functional magnetic resonance imaging (fMRI) with its property of high spatial resolution has energized the search for specific neural substrates of basic emotions and their feeling components. In the present article, we address the question as to whether recent fMRI studies on primary affective experiences have truly helped to pinpoint emotion-specific areas in the human brain or whether these studies are afflicted with methodological problems which make such inferences difficult. As one approach for improvement, we suggest the combination of fMRI with methods characterized by high temporal resolution, such as electroencephalography (EEG). Simultaneous recoding allows the correlation of temporally specific EEG components (e.g., the late positive potential) with regional blood-oxygen-level-dependent (BOLD) signals during affective experiences. Combined information on the source as well as the exact temporal pattern of a neural affective response will help to improve our understanding of emotion-specific brain activation.