Language context modulates reading route: an electrical neuroimaging study.

INTRODUCTION The orthographic depth hypothesis (Katz and Feldman, 1983) posits that different reading routes are engaged depending on the type of grapheme/phoneme correspondence of the language being read. Shallow orthographies with consistent grapheme/phoneme correspondences favor encoding via non-lexical pathways, where each grapheme is sequentially mapped to its corresponding phoneme. In contrast, deep orthographies with inconsistent grapheme/phoneme correspondences favor lexical pathways, where phonemes are retrieved from specialized memory structures. This hypothesis, however, lacks compelling empirical support. The aim of the present study was to investigate the impact of orthographic depth on reading route selection using a within-subject design. METHOD We presented the same pseudowords (PWs) to highly proficient bilinguals and manipulated the orthographic depth of PW reading by embedding them among two separated German or French language contexts, implicating respectively, shallow or deep orthography. High density electroencephalography was recorded during the task. RESULTS The topography of the ERPs to identical PWs differed 300-360 ms post-stimulus onset when the PWs were read in different orthographic depth context, indicating distinct brain networks engaged in reading during this time window. The brain sources underlying these topographic effects were located within left inferior frontal (German > French), parietal (French > German) and cingular areas (German > French). CONCLUSION Reading in a shallow context favors non-lexical pathways, reflected in a stronger engagement of frontal phonological areas in the shallow versus the deep orthographic context. In contrast, reading PW in a deep orthographic context recruits less routine non-lexical pathways, reflected in a stronger engagement of visuo-attentional parietal areas in the deep versus shallow orthographic context. These collective results support a modulation of reading route by orthographic depth.

Who is honest and why: Baseline activation in anterior insula predicts inter-individual differences in deceptive behavior

Humans engage in deceptive behavior that negatively affects others. The propensity to deceive is,however, characterized by vast inter-individual heterogeneity that is poorly understood. Attempts to investigate the origins of this heterogeneity have so far mainly relied on subjective measures and have shown little predictive power. Here, we used resting electroencephalography to measure objective and stable individual differences in neural baseline activation in combination with an ecologically valid deception paradigm. Results showed that task-independent baseline activation in the anterior insula, a brain area implicated in mapping internal bodily states and in representing emotional arousal and consciousfeelings, predicts individuals’ propensity for deceptive behavior. The higher the neural baseline activation in this area is, the lower individuals’ propensity to deceive. Moreover, results provide evidence that high baseline activation in the anterior insula is associated with negative affect and dispositional tendencies to avoid aversive emotional situations. These results provide converging neural and psychological evidence that individuals might avoid a deceptive act due to a highly active negative emotional system which would make a deceptive act too stressful and bothersome.

A neural marker of costly punishment behavior

Human readiness to incur personal costs to punish norm violators is a key force in the maintenance of social norms. The willingness to punish is, however, characterized by vast individual heterogeneity that is poorly understood. In fact, this heterogeneity has so far defied explanations in terms of individual-level demographic or psychological variables. Here, we use resting electroencephalography, a stable measure of individual differences in cortical activity, to show that a highly specific neural marker--baseline cortical activity in the right prefrontal cortex--predicts individuals' punishment behavior. The analysis of task-independent individual variation in cortical baseline activity provides a new window into the neurobiology of decision making by bringing dispositional neural markers to the forefront of the analysis.

Neural correlate of spatial presence in an arousing and noninteractive virtual reality: an EEG and psychophysiology study

Using electroencephalography (EEG), psychophysiology, and psychometric measures, this is the first study which investigated the neurophysiological underpinnings of spatial presence. Spatial presence is considered a sense of being physically situated within a spatial environment portrayed by a medium (e.g., television, virtual reality). Twelve healthy children and 11 healthy adolescents were watching different virtual roller coaster scenarios. During a control session, the roller coaster cab drove through a horizontal roundabout track. The following realistic roller coaster rides consisted of spectacular ups, downs, and loops. Low-resolution brain electromagnetic tomography (LORETA) and event-related desynchronization (ERD) were used to analyze the EEG data. As expected, we found that, compared to the control condition, experiencing a virtual roller coaster ride evoked in both groups strong SP experiences, increased electrodermal reactions, and activations in parietal brain areas known to be involved in spatial navigation. In addition, brain areas that receive homeostatic afferents from somatic and visceral sensations of the body were strongly activated. Most interesting, children (as compared to adolescents) reported higher spatial presence experiences and demonstrated a different frontal activation pattern. While adolescents showed increased activation in prefrontal areas known to be involved in the control of executive functions, children demonstrated a decreased activity in these brain regions. Interestingly, recent neuroanatomical and neurophysiological studies have shown that the frontal brain continues to develop to adult status well into adolescence. Thus, the result of our study implies that the increased spatial presence experience in children may result from the not fully developed control functions of the frontal cortex.

Electrophysiological indices of response inhibition in a Go/NoGo task predict self-control in a social context.

Recent research demonstrates that response inhibition-a core executive function-may subserve self-regulation and self-control. However, it is unclear whether response inhibition also predicts self-control in the multifaceted, high-level phenomena of social decision-making. Here we examined whether electrophysiological indices of response inhibition would predict self-control in a social context. Electroencephalography was recorded as participants completed a widely used Go/NoGo task (the cued Continuous Performance Test). Participants then interacted with a partner in an economic exchange game that requires self-control. Results demonstrated that greater NoGo-Anteriorization and larger NoGo-P300 peak amplitudes-two established electrophysiological indices of response inhibition-both predicted more self-control in this social game. These findings support continued integration of executive function and self-regulation and help extend prior research into social decision-making processes.

Das intrakranielle Meningeom: Befunde, Therapie und Ergebnisse bei neun Katzen und einem Hund

Nine cats and one dog with intracranial meningioma, which underwent surgery at the Department of Veterinary Surgery, University of Munich, Germany were evaluated retrospectively. One cat died shortly after surgery whereas the remaining 9 animals survived between 8 to 43 months (mean, 21.9 months) after surgery. Relapse was seen in 2 cats shortly after surgery and these animals were re-operated. After surgery, computed tomography was performed to ascertain that the tumour was completely removed. Pre-operative symptoms disappeared rapidly after surgery, except central blindness which persisted. Initial clinical observations and results of in vitro studies using feline meningioma cells indicated that hydroxy-urea can prolong survival time of affected animals.

The ovine cerebral venous system: comparative anatomy, visualization, and implications for translational research.

Cerebrovascular diseases are significant causes of death and disability in humans. Improvements in diagnostic and therapeutic approaches strongly rely on adequate gyrencephalic, large animal models being demanded for translational research. Ovine stroke models may represent a promising approach but are currently limited by insufficient knowledge regarding the venous system of the cerebral angioarchitecture. The present study was intended to provide a comprehensive anatomical analysis of the intracranial venous system in sheep as a reliable basis for the interpretation of experimental results in such ovine models. We used corrosion casts as well as contrast-enhanced magnetic resonance venography to scrutinize blood drainage from the brain. This combined approach yielded detailed and, to some extent, novel findings. In particular, we provide evidence for chordae Willisii and lateral venous lacunae, and report on connections between the dorsal and ventral sinuses in this species. For the first time, we also describe venous confluences in the deep cerebral venous system and an 'anterior condylar confluent' as seen in humans. This report provides a detailed reference for the interpretation of venous diagnostic imaging findings in sheep, including an assessment of structure detectability by in vivo (imaging) versus ex vivo (corrosion cast) visualization methods. Moreover, it features a comprehensive interspecies-comparison of the venous cerebral angioarchitecture in man, rodents, canines and sheep as a relevant large animal model species, and describes possible implications for translational cerebrovascular research.

Zazen meditation and no-task resting EEG compared with LORETA intracortical source localization

Meditation is a self-induced and willfully initiated practice that alters the state of consciousness. The meditation practice of Zazen, like many other meditation practices, aims at disregarding intrusive thoughts while controlling body posture. It is an open monitoring meditation characterized by detached moment-to-moment awareness and reduced conceptual thinking and self-reference. Which brain areas differ in electric activity during Zazen compared to task-free resting? Since scalp electroencephalography (EEG) waveforms are reference-dependent, conclusions about the localization of active brain areas are ambiguous. Computing intracerebral source models from the scalp EEG data solves this problem. In the present study, we applied source modeling using low resolution brain electromagnetic tomography (LORETA) to 58-channel scalp EEG data recorded from 15 experienced Zen meditators during Zazen and no-task resting. Zazen compared to no-task resting showed increased alpha-1 and alpha-2 frequency activity in an exclusively right-lateralized cluster extending from prefrontal areas including the insula to parts of the somatosensory and motor cortices and temporal areas. Zazen also showed decreased alpha and beta-2 activity in the left angular gyrus and decreased beta-1 and beta-2 activity in a large bilateral posterior cluster comprising the visual cortex, the posterior cingulate cortex and the parietal cortex. The results include parts of the default mode network and suggest enhanced automatic memory and emotion processing, reduced conceptual thinking and self-reference on a less judgmental, i.e., more detached moment-to-moment basis during Zazen compared to no-task resting.

Functional brain network efficiency predicts intelligence

The neuronal causes of individual differences in mental abilities such as intelligence are complex and profoundly important. Understanding these abilities has the potential to facilitate their enhancement. The purpose of this study was to identify the functional brain network characteristics and their relation to psychometric intelligence. In particular, we examined whether the functional network exhibits efficient small-world network attributes (high clustering and short path length) and whether these small-world network parameters are associated with intellectual performance. High-density resting state electroencephalography (EEG) was recorded in 74 healthy subjects to analyze graph-theoretical functional network characteristics at an intracortical level. Ravens advanced progressive matrices were used to assess intelligence. We found that the clustering coefficient and path length of the functional network are strongly related to intelligence. Thus, the more intelligent the subjects are the more the functional brain network resembles a small-world network. We further identified the parietal cortex as a main hub of this resting state network as indicated by increased degree centrality that is associated with higher intelligence. Taken together, this is the first study that substantiates the neural efficiency hypothesis as well as the Parieto-Frontal Integration Theory (P-FIT) of intelligence in the context of functional brain network characteristics. These theories are currently the most established intelligence theories in neuroscience. Our findings revealed robust evidence of an efficiently organized resting state functional brain network for highly productive cognitions.

Tonic activity level in the right prefrontal cortex predicts individuals' risk taking

Human risk taking is characterized by a large amount of individual heterogeneity. In this study, we applied resting-state electroencephalography, which captures stable individual differences in neural activity, before subjects performed a risk-taking task. Using a source-localization technique, we found that the baseline cortical activity in the right prefrontal cortex predicts individual risk-taking behavior. Individuals with higher baseline cortical activity in this brain area display more risk aversion than do other individuals. This finding demonstrates that neural characteristics that are stable over time can predict a highly complex behavior such as risk-taking behavior and furthermore suggests that hypoactivity in the right prefrontal cortex might serve as a dispositional indicator of lower regulatory abilities, which is expressed in greater risk-taking behavior.

An electrophysiological investigation of emotional change: preliminary data

Many psychotherapy researchers agree that emotional change is critical to therapeutic progress. In emotion-focused and Gestalt therapy, one technique to foster emotional change is the empty chair dialogue. Psychotherapy research has yielded ample evidence that this technique helps to alleviate longstanding interpersonal grievances (‘unfinished business’) and facilitates emotional change. Until now, little is known about the neurophysiological correlates of such emotional change. The present study thus aims at adding a further level of analysis to psychotherapy research, and may enrich knowledge about mechanisms of change. Neurophysiological correlates of emotional change were investigated using multi-channel electroencephalography. Individuals experiencing ‘unfinished business’ were guided by experienced therapists to participate in an empty chair dialogue. Event-related brain potentials were recorded before and after the intervention while participants were viewing pictures of the person central to their interpersonal grievance as well as pictures of control persons. Event related potentials are compared regarding topography and overall signal strength. Preliminary results will be discussed regarding neurophysiological mechanisms of action potentially occurring during emotional change.

A Neural Trait Approach to Exploring Individual Differences in Social Preferences

Research demonstrates that social preferences are characterized by significant individual differences. An important question, often overlooked, is from where do these individual differences originate? And what are the processes that underlie such differences? In this paper, we outline the neural trait approach to uncovering sources of individual differences in social preferences, particularly as evidenced in economic games. We focus on two primary methods—resting-state electroencephalography and structural magnetic resonance imaging—used by researchers to quantify task-independent, brain-based characteristics that are stable over time. We review research that has employed these methods to investigate social preferences with an emphasis on a key psychological process in social decision-making; namely, self-control. We then highlight future opportunities for the neural trait approach in cutting-edge decision-making research. Finally, we explore the debate about self-control in social decision-making and the potential role neural trait research could play in this issue.

Radiological findings of sexual intercourse related emergency department admissions: a first overview

OBJECTIVES Sexuality is an essential aspect of human function, well-being and quality of life. Many people have sex without complications. However, there are some people who need to seek emergency medical help for related health problems. The aim of this study was to present a first overview of patients who received a radiological examination related to sexual intercourse based emergency department admission. METHODS Our centralized electronic patient record database was reviewed for patients who had been admitted to our emergency department with an emergency after sexual intercourse between 2000 and 2011. The database was scanned for the standardized key words 'sexual intercourse' or 'coitus' retrospectively. For all patients identified in the electronic patient record database the radiological examinations were searched for manually in our Radiology Information System, and reviewed by three independent radiologists. RESULTS One hundred and twenty nine out of 445 (29,0%) patients received a radiological examination after immediate emergency department admission related to sexual intercourse. Fifty two out of 129 (40.3%) patients had positive radiological findings while 77 (59.7%) did not. Eighty point seven percent (n = 42) of the radiological findings were a sexual intercourse-associated pathology and 19.2% (n = 10) were considered to be incidental findings. Age and male sex positively correlated with radiological imaging workup (p<0.001, respectively p<0.037). The most common sexual intercourse-associated pathology was headache attributed to cerebrovascular insult (n = 21, 40.3%) followed by epididymitis (n = 7, 16.6%) and obstructive uropathy (n = 5, 11.6%). Of the patients with headache attributed to non-traumatic intracranial hemorrhage, subarachnoid hemorrhage (n = 14, 66.6%) was the most common, followed by intracerebral bleeding (n = 4, 19.0%) and one subdural hemorrhage. CONCLUSIONS Pathological findings are manifold. Cerebral imaging is the most common type of radiological imaging performed. Further prospective and standardized studies should be performed to better evaluate the significance of radiological imaging in this patient collective with the aim to gain better knowledge on what patients profit from what type of radiological imaging when presenting with a sexual intercourse related emergency. ADVANCES IN KNOWLEDGE The present study provides a first overview on radiological findings of sexual intercourse related emergency department admissions.

Imaging of acute ischemic stroke.

BACKGROUND Over 80% of strokes result from ischemic damage to the brain due to an acute reduction in the blood supply. Around 25-35% of strokes present with large vessel occlusion, and the patients in this category often present with severe neurological deficits. Without early treatment, the prognosis is poor. Stroke imaging is critical for assessing the extent of tissue damage and for guiding treatment. SUMMARY This review focuses on the imaging techniques used in the diagnosis and treatment of acute ischemic stroke, with an emphasis on those involving the anterior circulation. Key Message: Effective and standardized imaging protocols are necessary for clinical decision making and for the proper design of prospective studies on acute stroke. CLINICAL IMPLICATIONS Each minute without treatment spells the loss of an estimated 1.8 million neurons ('time is brain'). Therefore, stroke imaging must be performed in a fast and efficient manner. First, intracranial hemorrhage and stroke mimics should be excluded by the use of computed tomography (CT) or magnetic resonance imaging (MRI). The next key step is to define the extent and location of the infarct core (values of >70 ml, >1/3 of the middle cerebral artery (MCA) territory or an ASPECTS score ≤ 7 indicate poor clinical outcome). Penumbral imaging is currently based on the mismatch concept. It should be noted that the penumbra is a dynamic zone and can be sustained in the presence of good collateral circulation. A thrombus length of >8 mm predicts poor recanalization after intravenous thrombolysis.

Inhibition of matrix metalloproteinases attenuates brain damage in experimental meningococcal meningitis.

BackgroundApproximately 7% of survivors from meningococcal meningitis (MM) suffer from neurological sequelae due to brain damage in the course of meningitis. The present study focuses on the role of matrix metalloproteinases (MMPs) in a novel mouse model of MM-induced brain damage.MethodsThe model is based on intracisternal infection of BALB/c mice with a serogroup C Neisseria meningitidis strain. Mice were infected with meningococci and randomised for treatment with the MMP inhibitor batimastat (BB-94) or vehicle. Animal survival, brain injury and host-response biomarkers were assessed 48 h after meningococcal challenge.ResultsMice that received BB-94 presented significantly diminished MMP-9 levels (p¿<¿0.01), intracerebral bleeding (p¿<¿0.01), and blood-brain barrier (BBB) breakdown (p¿<¿0.05) in comparison with untreated animals. In mice suffering from MM, the amount of MMP-9 measured by zymography significantly correlated with both intracerebral haemorrhage (p¿<¿0.01) and BBB disruption (p¿<¿0.05).ConclusionsMMPs significantly contribute to brain damage associated with experimental MM. Inhibition of MMPs reduces intracranial complications in mice suffering from MM, representing a potential adjuvant strategy in MM post-infection sequelae.