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Post-traumatic stress disorder (PTSD) symptoms are present across cultures, with the only differences being the indigenous ways in which affected individuals deal with them. Hence, there must be a common underlying basis for these symptoms. The development of an intense memory for the traumatic experiences encountered, and associated neurobiological alterations, may explain the cross-cultural occurrence of similar PTSD symptoms.

Insecure and violent environments foster two different forms of aggressive behavior: reactive aggressive responding, such as fearful or angry impulsive behavior to perceived threats, and appetitive aggression, which encompasses violence-related feelings of power, excitement, and pleasure. We tested whether forensic offender rehabilitation narrative exposure therapy (FORNET; five sessions) would reduce involvement in everyday violence and produce beneficial effects for mental and physical health. In a Burundian residential center for former street children, we identified a subset of 32 male youths (mean age = 17 years) who scored highly in appetitive aggression. We conducted a randomized controlled trial by assigning matched pairs to receive either FORNET or treatment as usual. During the follow-up (4–7 months after completing treatment), the 16 youths who received FORNET reported having committed significantly fewer offenses (Hedges’s g = 0.62) and presented with fewer physical-health complaints (Hedges’s g = 0.56) than did their matched control participants.

Over the past three decades, research and clinical practice related to the field of traumatic stress have developed tremendously. In parallel with the steady accumulation of basic knowledge, therapeutic approaches have been developed to treat people suffering from posttraumatic stress disorder (PTSD) and other trauma-related psychological problems. Today, a number of evidence-based treatments are available. They differ in various ways; however, they also have a number of commonalities. Given this situation, clinicians may wonder which treatment program to use, or more specifically, which treatment components are critical for a successful therapy. In this article, seven pioneers who have developed empirically supported psychotherapies for trauma-related disorders were asked to compose an essay of three parts: first, to provide a brief summary of the treatment they have developed; second, to identify three key interventions that are common and critical in treating PTSD; and third, to suggest important topics and future directions for research. The paper ends with a summary highlighting the identified commonalities (psychoeducation; emotion regulation and coping skills; imaginal exposure; cognitive processing, restructuring, and/or meaning making; emotions; and memory processes), pointing to future directions such as trying to better understand the underlying mechanisms of action, and developing treatments that are tailored to the needs of different patient groups.Keywords: Psychotraumatology; posttraumatic stress disorder; complex PTSD; psychotherapy; exposure; cognitive restructuring; psychoeducation(Published: 14 August 2015)For the abstract or full text in other languages, please see Supplementary files in the column to the right (under ‘Article Tools’)Citation: European Journal of Psychotraumatology 2015, 6: 28186 - http://dx.doi.org/10.3402/ejpt.v6.28186

This article is a revision of the previous edition article by M. Basoglu, volume 23, pp. 15779–15783, © 2001, Elsevier Ltd.

We used the 40-Hz auditory steady-state response (SSR) to compare for the first time tonotopic frequency representations in the region of primary auditory cortex (PAC) between subjects with chronic tinnitus and hearing impairment and normal hearing controls. Frequency representations were measured in normal hearing (n=17) and tinnitus (n=28) subjects using eight carrier frequencies between 384 and 6561 Hz, each amplitude modulated (AM) at 40-Hz on trials of 3 min duration under passive attention. In normal hearing subjects, frequency gradients were observed in the medial-lateral, anterior-posterior, and inferior-superior axes, which were consistent with the orientation of Heschl's gyrus and with functional organization revealed by fMRI investigations. The frequency representation in the right hemisphere was approximately 5 mm anterior and approximately 7 mm lateral to that in the left hemisphere, corroborating with MEG measurements hemispheric asymmetries reported by cytoarchitectonic studies of the PAC and by MRI morphometry. In the left hemisphere, frequency gradients were inflected near 2 kHz in normal hearing subjects. These SSR frequency gradients were attenuated in both hemispheres in tinnitus subjects. Dipole power was also elevated in tinnitus, suggesting that more neurons were entrained synchronously by the AM envelope. These findings are consistent with animal experiments reporting altered tonotopy and changes in the response properties of auditory cortical neurons after hearing loss induced by noise exposure. Degraded frequency representations in tinnitus may reflect a loss of intracortical inhibition in deafferented frequency regions of the PAC after hearing injury.

Schizophrenia is typically associated with cognitive deficits, but symptoms also point to alterations in the processing of affective material, with potential impact on behavioral performance. This impact may unfold on multiple time scales, but initial processing of rapidly unfolding social cues may be particularly important. MEG-assessed regional brain activity associated with the capacity to process the emotional content of rapid visual stimuli (3/s) was examined in 12 individuals with schizophrenia and 12 matched controls. Patients showed less differentiation of emotional versus neutral stimuli 90-300 ms following picture onset. Together with group differences in the lateral topography of valence effects, these results are discussed as evidence of deficient automatic processing of emotionally potent stimuli in schizophrenia.

Converging electrophysiological and hemodynamic findings indicate sensory processing of emotional pictures is preferred to that of neutral pictures. Whereas neuroimaging studies of emotional picture perception have employed stimulus durations lasting several seconds, recent electrocortical investigations report early visual cortical discrimination between emotionally arousing and neutral picture processing. Here, we use a hybrid picture presentation paradigm covering a range of rapid presentation rates (0.75-6 Hz), while visual system activity is recorded with functional magnetic resonance imaging. Results demonstrate widespread sensitivity to emotional arousal in the secondary and inferior temporal visual cortex. Furthermore, activity in the lateral inferior occipital and medial inferior temporal visual cortex revealed equivalent emotion-sensitive activation across all presentation rates. Results further support the notion that attention and perceptual processing are in part directed by underlying motivational systems.

Gamma-band activity (GBA) bursts have been viewed as a signature for ignitions in localized Hebbian cell assemblies and are thought to indicate active memory. Using whole-head magnetoencephalography, we recorded focal bursts of GBA during chess playing. Unlike highly skilled chess grandmasters, with amateur chess players focal gamma bursts prevailed in deeper structures in the region of the medial temporal lobes. This observation is consistent with the interpretation of memory formation in amateur chess players. For the frontal and parietal cortex the relationship was reversed, with more frequent gamma bursts found in chess grandmasters, indicating that the retrieval of chunks from expert memory is based on the recruitment of these neocortical areas. The results suggest the possibility that time-dependent reorganization during the formation of expert memory can be studied in humans and support the theory that the medial temporal lobe and hippocampal formation play a transitional role during the creation of expert memory in the neocortex.

Psychotherapie verändert klinische Symptome und mentale Funktionen und damit auch Leistungen des Gehirns. Dies bedeutet, dass sich die Architektur des Gehirns durch erfolgreiche therapeutische Intervention modifizieren lässt. Tatsächlich kann der Nachweis sogar auf makroskopischer Ebene gelingen, wie wir hier am Beispiel der Behandlung seelischer Erkrankungen in Folge von traumatischem Stress darlegen. Die Narrative Expositionstherapie (NET) wurde dabei mit Standardbehandlungen (TU; treatment as usual) bei traumatisierten Asylsuchenden in Deutschland verglichen. Der Erfolg der NET spiegelte sich nicht nur in den Symptomkennwerten wider, sondern auch in neuromagnetischen Messungen. Diese zeigten in der 6-Monats-Katamnese, dass sich die Hirnaktivität in der NET-Gruppe an diejenige einer psychisch unauffälligen Normstichprobe angenähert hatte. In der TU-Gruppe war dies nicht der Fall. Neurophysiologische Messungen können somit (1) den Therapieerfolg validieren, (2) Wirkmechanismen einer Therapieform überprüfen, wodurch ein Zugang zu besserer Modellierung geschaffen wird, (3) die differentialdiagnostischen Möglichkeiten erweitern und (4) uns einmal mehr lehren, dass Geist und Gehirn lediglich zwei Informationsebenen ein und desselben Phänomens darstellen.

Objective: The possibility of simultaneously observing activation of primary and secondary auditory cortices has been demonstrated by Engelien et al. [Hear Res 2000;148:153 – 60]. Methods: Such a dual monitoring by means of neuromagnetic recordings can be achieved when a subject is stimulated by brief pulses of 40 Hz-modulated tones. Depending on the frequency filter applied, either the steady-state field (SSF) or the N1m can be extracted from the evoked magnetic field complex. Results: Using this ‘combined’ (two-maps) paradigm with 4 carrier frequencies, we show that it is possible to synchronously screen two tonotopic maps—one map each reflected either by the SSF or the N1m. Indicators are the systematic variation in the location (higher frequencies are more posterior) and orientation (higher frequencies oriented differently in the saggital plane) of the equivalent current dipole (ECD). These parameters were compared with those obtained from ‘classic’ (one map) paradigms in which either a pure tone elicits an N1m or a 40 Hz continuous (3 s) stimulation produces an SSF. Overall the results were similar, however, systematic differences between the paradigms were found for ECD localization, dipole strength, amplitude, and phase. Conclusions and Significance: One possible interpretation of these results is that different tonotopically arranged cortical fields were involved in the generation of the components. q 2004 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Focal electromagnetic slow-wave activity is generated in the vicinity of brain lesions. The present study confirmed this for the EEG delta band (1-4 Hz): Activity in the waking state was pronounced over the hemisphere of the lesion in 11 stroke patients suffering from aphasia, but not in 10 healthy controls. Changes of abnormal slow waves patterns were tracked from 1-3 months to 2 years poststroke by recording the EEG five times at 4-month intervals. Across the first year poststroke, mean left-hemispheric delta amplitude and equivalent current dipole strength decreased in parallel with the spontaneous recovery of language function, whereas the regional distribution of delta activity sources was stabile across time. No changes were observed during the second year poststroke. Results suggest that abnormal slow waves in the vicinity of brain lesions may be related to impairment in brain function, and that their measurement may assist in depicting the course of functional recovery.

Zusammenfassung: Gehirnwissenschaftliche Erkenntnisse haben in den vergangenen Jahren zur Entwicklung neuer Therapieformen in der neurologischen und neuropsychologischen Rehabilitationsforschung gefuhrt. Allgemeine Prinzipien, die diesen neuen Verfahren zugrunde liegen, lassen sich mit den Termini Intensivierung, Verhaltensrelevanz und Fokussierung umreisen. Intensivierung der Therapie bedeutet, dass die Intervention mit besonders hoher Frequenz durchgefuhrt wird (engl.: massed practice). Die neuen Verfahren sind zunehmend verhaltensrelevant, was bedeutet, dass die im therapeutischen Setting implementierten Interaktionstypen denjenigen in alltaglichen Lebenszusammenhangen gleichen (behavioral relevance). Schlieslich bedeutet «Fokussierung», dass der Patient durch Hilfsmittel und Regeln der therapeutischen Interaktion zu Handlungsweisen gebracht wird, die er aufgrund operanter Konditionierungen in Folge der Gehirnschadigung sonst vermeiden wurde (constraints to avoid learned nonuse). In einer kontrollierten Effektivitatsstudie konnten wir beweisen, dass intensive verhaltensrelevante und fokussierte Sprachtherapie auch bei langjahriger und chronischer Aphasie zu einer signifikanten Verbesserung der sprachlichen Leistungen fuhren kann – diese Verbesserung manifestierte sich sowohl in klinischen Tests als auch in der Selbst- und Fremdeinschatzung. Wir gehen hier auf die historischen Wurzeln des neuen Verfahrens ein und diskutieren anstehende Fragen fur zukunftige Forschungen. Schlusselworter: Aphasie, Neuropsychologische Rehabilitation, Intensivierung, Neurowissenschaft englischer Titel fehlt Summary: This article introduces a new approach to neuropsychological therapy of chronic language disturbances called Constraint-Induced Aphasia (CIA) therapy. General principles that are at the heart of the new procedure include massed practice, behavioral relevance, and the application of constraints to prevent learned nonuse. Massed practice implies an intensive application of therapy, with high frequency (several hours per day). In behaviorally relevant therapeutic settings, the practicing of impaired functions is done in a context that resembles everyday activities. The new therapeutic approach uses constraints, for example by introducing rules and instrumental aids, that focus the patient on performing actions he would normally avoid due to aversive conditioning consequent to brain lesion (learned nonuse). In a controlled clinical trial, we were able to demonstrate the success of CIA therapy, a new therapeutic approach that follows all these general principles, in stroke patients with chronic language disability. We address the theoretical foundations of CIA therapy, its historical roots and some issues for future research.

A new set of techniques allows for the study of brain function by near-infrared light, exploiting two optical phenomena: Changes in light absorption are determined by changes in the concentration of substances like oxy-and deoxy-hemoglobin, and changes in light scattering occur as a consequence of variations of properties of membranes and corpuscles in the neural tissue. Methods based on light absorption can be used to study hemodynamic changes in the brain, whereas those based on light scattering can be used to study neuronal activity and to provide anatomical information at a cellular and subcellular level. Three optical imaging approaches can be used to study living tissue: reflection, optical coherence tomography (OCT), and photon migration. These three approaches vary in their penetration (from less than a millimeter for reflection to up to 3-5 cm for photon migration) and spatial resolution (from a micron level for reflection and OCT to a millimeter and centimeter level for photon migration). This issue includes a collection of articles reviewing applications of these technologies to the study of brain and other bodily functions in humans.

In various studies, deviances of hemispheric laterality in the organization of the perisylvian region in dyslexia have been suggested. Although associated with impaired language functioning, the clinical significance of atypical cerebral lateralization remains unclear. The present study examined interhemispheric source differences of magnetic responses to the German synthetic syllable [ba:] in the auditory cortex of 14 dyslexic children and 12 normally literate controls aged 8‐15 years. In all subjects, two main deflections, P100m and N260m, were evident in the responses over each hemisphere. While in the control group the right P100m dipole was located more anterior than the corresponding dipole of the left hemisphere, the dyslexic group displayed a rather symmetrical source configuration between the hemispheres. This symmetry reflected a deviance in the right perisylvian region for the dyslexic subjects’ P100m, which was generated � 1 cm more posterior than the response in controls. The deviation was also obvious relative to the source location of the later component, N260m, which did not systematically differ between the participant groups. Our results suggest that the altered hemispheric asymmetry reflects an atypical organization of the right hemisphere in children and adolescents with dyslexia.

A part of the core area of the auditory cortex was examined in nine blind and 10 sighted individuals by magnetic source imaging and was found to be enlarged by a factor of 1.8 in the blind compared with the sighted humans. Moreover, the latency of the N1m component of the auditory-evoked magnetic response was significantly decreased in the blind. The development of use-dependent cortical reorganization may be a consequence of the absence of visual input in combination with enhanced auditory activity generated by the long-term concentration by blind individuals on nonvisual cues to interact appropriately with the environment. It is consistent with and well suited to mediate the demonstrated increased ability of the blind to accurately localize acoustic sources in peripheral auditory fields and to decode speech.

Background: Patients suffering from Alzheimer’s disease exhibit more activity in the conventional electroencephalographic delta and theta bands. This activity concurs with atrophy and reduced metabolic and perfusion rates, particularly in temporoparietal structures. Methods: Whole-head magnetoencephalographic recordings were obtained from 15 patients diagnosed with Alzheimer’s disease and 19 healthy control subjects during a resting condition. The generators of focal magnetic slow waves were located employing a single moving dipole model. Results: Dipole density in the delta and theta bands was enhanced in the Alzheimer’s disease group compared with healthy control subjects. Slow-wave activity differed significantly between groups in temporoparietal regions of both hemispheres. Right temporoparietal slow-wave activity covaried with cognitive performance, whereas left temporal delta activity varied with a functional status scale. Conclusions: Our results support the predominant role of the temporoparietal areas in the diagnosis of Alzheimer’s disease. Magnetoencephalography and the source analysis of focal slow activity in particular provide interesting and potentially clinically useful tools to assess functional modifications of patients’ brain and to evaluate its relationship with the cognitive status.

Although neural activity associated with emotion is becoming better understood, the influence of affective parameters on brain activity reflecting cognitive functioning in humans remains poorly characterized. We examined affective influences on working memory (WM) and tested the hypotheses that (i) dorsolateral prefrontal cortex (DLPFC) activity reflecting WM is influenced by the emotion-evoking qualities of task-relevant stimuli, but only when brought “on-line” by task demands, and (ii) DLPFC and orbitofrontal cortex (OFC) activities are inversely related as a function of emotional valence. Participants performed two tasks while event-related functional MRI measured brain activity; one task required active maintenance of stimulus representations in WM, and the other task required target detection responses with no demand for WM. Stimuli were standardized emotional (pleasant and unpleasant) and neutral pictures. Emotional stimuli differentially influenced DPFC and OFC activity during WM; DLPFC was influenced by emotional valence, enhanced by pleasant and reduced by unpleasant, compared to neutral stimuli, only when task conditions required WM. OFC was valence-sensitive during both tasks, greater to arousing than neutral stimuli when WM demand was low and in inverse relationship to DLPFC with high WM demand. Further, DLPFC and OFC activities are inversely related with respect to emotional valence during the WM task. The results are consistent with the hypothesis that the intrinsic valence of task-relevant stimuli maintained in WM modulates DLPFC activity but only when the DLPFC is required for task demands. Findings suggest a conceptualization of DLPFC and its involvement in WM that takes into account a role for affective parameters.

We describe a methodology to apply current source density (CSD) and minimum norm (MN) estimation as pre-processing tools for time-series analysis of single trial EEG data. The performance of these methods is compared for the case of wavelet time-frequency analysis of simulated gamma-band activity. A reasonable comparison of CSD and MN on the single trial level requires regularization such that the corresponding transformed data sets have similar signal-to-noise ratios (SNRs). For region-of-interest approaches, it should be possible to optimize the SNR for single estimates rather than for the whole distributed solution. An effective implementation of the MN method is described. Simulated data sets were created by modulating the strengths of a radial and a tangential test dipole with wavelets in the frequency range of the gamma band, superimposed with simulated spatially uncorrelated noise. The MN and CSD transformed data sets as well as the average reference (AR) representation were subjected to wavelet frequency-domain analysis, and power spectra were mapped for relevant frequency bands. For both CSD and MN, the influence of noise can be sufficiently suppressed by regularization to yield meaningful information, but only MN represents both radial and tangential dipole sources appropriately as single peaks. Therefore, when relating wavelet power spectrum topographies to their neuronal generators, MN should be preferred.

Stress during pregnancy may impact subsequent generations, which is demonstrated by an increased susceptibility to childhood and adulthood health problems in the children and grandchildren. Although the importance of the prenatal environment is well reported with regards to future physical and emotional outcomes, little is known about the molecular mechanisms that mediate the long-term consequences of early stress across generations. Recent studies have identified DNA methylation as a possible mediator of the impact of prenatal stress in the offspring. Whether psychosocial stress during pregnancy also affects DNA methylation of the grandchildren is still not known. In the present study we examined the multigenerational hypothesis, that is, grandmaternal exposure to psychosocial stress during pregnancy affecting DNA methylation of the grandchildren. We determined the genome-wide DNA methylation profile in 121 children (65 females and 56 males) and tested for associations with exposure to grandmaternal interpersonal violence during pregnancy. We observed methylation variations of five CpG sites significantly (FDR amp;lt; 0.05) associated with the grandmothers report of exposure to violence while pregnant with the mothers of the children. The results revealed differential methylation of genes previously shown to be involved in circulatory system processes (FDRo0.05). This study provides support for DNA methylation as a biological mechanism involved in the transmission of stress across generations and motivates further investigations to examine prenatal-dependent DNA methylation as a potential biomarker for health problems. Funding Agencies|European Research Council (ERC) through ERC advanced grant [323977]; CAPES/DAAD [18354/12-2]

Street children are exposed to violence, and subsist in poor and generally precarious conditions. In conflict regions, institutional care facilities are often the only well established way to care for vulnerable children. Providing access to school education is considered to be key to allow successful integration into society. However, adverse effects of psychological disorders may pose another serious obstacle. In semi-structured interviews in a sample of 112 Burundian male youths (mean age = 15.9 years), we assessed exposure to traumatic stressors, regularly and recently occurring violence as well as prevalence of posttraumatic stress disorder (PTSD), depression, substance dependence, suicidal risk, and progress in school. Former street children (n = 32) and other vulnerable children (n = 50) in a residential center were compared to children living in the streets (n = 15) or with families (n = 15). While the children living in the center were less regularly exposed to violence and reported less substance dependence than street children, PTSD symptoms were common among the former street children. Furthermore, we provided empirical evidence that for the children living in the center, recently experienced violence – mostly minor physical conflicts, psychological violence and neglect – was associated with increased PTSD symptomatology and impeded progress in school. In a population of children who experienced many traumatic incidences and a lot of violence, even minor violent events may trigger and reinforce PTSD symptoms. Hence controlling exposure to violence and addressing mental ill-health in vulnerable children is mandatory for reintegration.

Background : Compared to DSM-IV, the criteria for diagnosing posttraumatic stress disorder (PTSD) have been modified in DSM-5. Objective : The first aim of this study was to examine how these modifications impact rates of PTSD in a sample of Congolese ex-combatants. The second goal of this study was to investigate whether PTSD symptoms were associated with perpetrator-related acts or victim-related traumatic events. Method : Ninety-five male ex-combatants in the eastern Democratic Republic of Congo were interviewed. Both the DSM-IV and the DSM-5 PTSD symptom criteria were assessed. Results : The DSM-5 symptom criteria yielded a PTSD rate of 50% ( n =47), whereas the DSM-IV symptom criteria were met by 44% ( n= 42). If the DSM-5 would be set as the current “gold standard,” then DSM-IV would have produced more false negatives (8%) than false positives (3%). A minority of participants (19%, n =18) indicated an event during which they were involved as a perpetrator as their most stressful event. Results of a regression analysis ( R 2 =0.40) showed that, after accounting for the number of types of traumatic events, perpetrated violent acts were not associated with the symptom severity of PTSD. Conclusions : The findings demonstrate that more diagnostic cases were produced with the DSM-5 diagnostic rules than were dropped resulting in an increase in PTSD rates compared to the DSM-IV system. The missing association between PTSD symptoms and perpetrated violent acts might be explained by a potential fascinating and excited perception of these acts. Keywords: PTSD; DSM-5; DSM-IV; Congo; ex-combatants; violence Responsible Editor: Stuart Turner, Trauma Clinic, London, United Kingdom. For the abstract or full text in other languages, please see Supplementary files in the column to the right (under ‘Article Tools’). (Published: 25 February 2015) Citation: European Journal of Psychotraumatology 2015, 6 : 24981 - http://dx.doi.org/10.3402/ejpt.v6.24981

Background Current knowledge is limited regarding patient characteristics related to treatment outcome of posttraumatic stress disorders (PTSD) in refugees and asylum seekers. Objective Gender, torture status, offender status, level of anger, and level of depression were investigated for possible effects on the treatment outcome. Method Patient characteristics were explored in 54 refugees and asylum seekers who had completed a treatment program for PTSD. Non-responders (10), those who had the same or higher levels of symptom severity after treatment, were compared with responders, those who had lower symptom severity after treatment (44). Symptom severity was measured by Clinician-Administered PTSD Scale. The non-responders and responders constituted the dichotomous, dependent variable. The independent variables were gender, torture status, offender status, level of anger, and level of depression. T-tests and Exact Unconditional Homogeneity/Independence Tests for 2X2 Tables were used to study the relationship to treatment outcome. Results Being male and reporting to have been a violent offender were significantly more frequent characteristics among the non-responders compared to the responders. The levels of pretreatment anger, depression and torture status did not affect the treatment outcome. Conclusions The study adds support to findings that females benefit more from treatment of PTSD than males and that violent offenders are difficult to treat within the standard treatment programs. © 2014 Håkon Stenmark et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 Unported (CC-BY 4.0) License (http://creativecommons.org/licenses/by/4.0/), allowing third parties to copy and redistribute the material in any medium or format, and to remix, transform, and build upon the material, for any purpose, even commercially, under the condition that appropriate credit is given, that a link to the license is provided, and that you indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.

A good memory for emotionally arousing experiences may be intrinsically adaptive, as it helps the organisms to predict safety and danger and to choose appropriate responses to prevent potential harm. However, under conditions of repeated exposure to traumatic stressors, strong emotional memories of these experiences can lead to the development of trauma-related disorders such as posttraumatic stress disorder (PTSD). This syndrome is characterized by distressing intrusive memories that can be so intense that the survivor is unable to discriminate past from present experiences.This selective review on the role of memory-related genes in PTSD etiology is divided in three sections. First, we summarize studies indicating that the likelihood to develop PTSD depends on the cumulative exposure to traumatic stressors and on individual predisposing risk factors, including a substantial genetic contribution to PTSD risk. Second, we focus on memory processes supposed to be involved in PTSD etiology and present evidence for PTSD-associated alterations in both implicit (fear conditioning, fear extinction) and explicit memory for emotional material. This is supplemented by a brief description of structural and functional alterations in memory-relevant brain regions in PTSD. Finally, we summarize a selection of studies indicating that genetic variations found to be associated with enhanced fear conditioning, reduced fear extinction or better episodic memory in human experimental studies can have clinical implications in the case of trauma exposure and influence the risk of PTSD development. Here, we focus on genes involved in noradrenergic (ADRA2B), serotonergic (SLC6A4), and dopaminergic signaling (COMT) as well as in the molecular cascades of memory formation (PRKCA and WWC1). This is supplemented by initial evidence that such memory-related genes might also influence the response rates of exposure-based psychotherapy or pharmacological treatment of PTSD, which underscores the relevance of basic memory research for disorders of altered memory functioning such as PTSD.

Aggressive behavior in children and youths is commonly associated with exposure to violence and maltreatment. Consequently, aggressive behavior has often been explained as a form of reactive behavior in response to violence-inflicted mental suffering. However, perpetrating violence can become appealing, fascinating and exciting, i.e., may acquire appetitive, self-rewarding aspects. We postulated that this appetitive form of aggression reduces the vulnerability for developing Posttraumatic Stress Disorder (PTSD) in insecure and violent environments. Furthermore we investigated the extent to which reactive aggression and appetitive aggression account for recent violent behavior in children and youths. We conducted semi-structured interviews in a sample of 112 children and youths (Mage=15.9 years) recruited from the streets, families and a residential center for vulnerable children in Burundi. We investigated the cumulative exposure to traumatic events and to domestic and community violence, assessed the recently committed offenses, the severity of PTSD symptoms, and the potential for reactive and appetitive aggression. Reactive aggression was positively related to PTSD, whilst appetitive aggression was negatively related to PTSD. Children higher in appetitive aggression were also more likely to display violent behavior. These results suggest that an appetitive perception of violence may be an useful adaption to insecure and violent living conditions reducing the vulnerability of children for trauma-related mental disorders. However, positive feelings experienced through violent or cruel behavior are also an important risk factor for ongoing aggressive behavior and therefore need to be considered in prevention strategies.

Contains fulltext : 135874.pdf (Publisher’s version ) (Open Access) Recent evidence suggests that altered expression and epigenetic modification of the glucocorticoid receptor gene (NR3C1) are related to the risk of post-traumatic stress disorder (PTSD). The underlying mechanisms, however, remain unknown. Because glucocorticoid receptor signaling is known to regulate emotional memory processes, particularly in men, epigenetic modifications of NR3C1 might affect the strength of traumatic memories. Here, we found that increased DNA methylation at the NGFI-A (nerve growth factor-induced protein A) binding site of the NR3C1 promoter was associated with less intrusive memory of the traumatic event and reduced PTSD risk in male, but not female survivors of the Rwandan genocide. NR3C1 methylation was not significantly related to hyperarousal or avoidance symptoms. We further investigated the relationship between NR3C1 methylation and memory functions in a neuroimaging study in healthy subjects. Increased NR3C1 methylation-which was associated with lower NR3C1 expression-was related to reduced picture recognition in male, but not female subjects. Furthermore, we found methylation-dependent differences in recognition memory-related brain activity in men. Together, these findings indicate that an epigenetic modification of the glucocorticoid receptor gene promoter is linked to interindividual and gender-specific differences in memory functions and PTSD risk. 11 p.

The aims of this study were to examine rates and risk factors for prolonged grief and to investigate the association between prolonged grief and depression. The authors interviewed a heterogeneous bereaved sample of 61 Germans, 6 of whom had prolonged grief and depression, respectively. The 2 syndromes were strongly linked to one another. Risk factors for prolonged grief were being a woman and having high levels of religious beliefs and low levels of satisfaction with one's religious beliefs, emotional closeness to the deceased, and unanticipated loss. Symptoms of prolonged grief may endure years post-loss and often overlap with depression.

While the relationship between reading and spelling disabilities has been reported for many European orthographies, very few studies have been conducted on other types of orthographies. The current chapter studies the relationship between reading and spelling deficits in Arabic based on an epidemiological survey of these deficits in Arabic-speaking children in Egypt. We screened a sample of 1106 Arabic-speaking third graders for their reading and spelling abilities. The prevalence rate for combined deficits in reading as well as spelling was high (12.6 %), but very low for isolated deficits in reading (0.9 %) or spelling (1.1 %). Importantly, we observed less dissociation of reading and spelling in vowelized Arabic compared to shallow orthographies such as German. This finding has implications for word processing in Arabic and it highlights the need for further studies of both typical and atypical development of literacy skills in Arabic-speaking children.

Aggressive behavior is thought to divide into two motivational elements: The first being a self-defensively motivated aggression against threat and a second, hedonically motivated “appetitive” aggression. Appetitive aggression is the less understood of the two, often only researched within abnormal psychology. Our approach is to understand it as a universal and adaptive response, and examine the functional neural activity of ordinary men (N = 50) presented with an imaginative listening task involving a murderer describing a kill. We manipulated motivational context in a between-subjects design to evoke appetitive or reactive aggression, against a neutral control, measuring activity with Magnetoencephalography (MEG). Results show differences in left frontal regions in delta (2–5 Hz) and alpha band (8–12 Hz) for aggressive conditions and right parietal delta activity differentiating appetitive and reactive aggression. These results validate the distinction of reward-driven appetitive aggression from reactive aggression in ordinary populations at the level of functional neural brain circuitry.

The present study aimed at examining the oscillatory brain-electric correlates of human operant learning using high-density electroencephalography (EEG). Induced gamma-band activity (GBA) was studied using a fixed-interval reinforcement schedule with a variable limited hold period, which was decreased depending on response accuracy. Thus, participants' behavior was shaped during the course of the learning session. After each response, numbers indicating the money value of that response served as reinforcing stimuli. Random reinforcement and self-paced button pressing without reinforcement were added as control conditions. GBA around 40 Hz was enhanced at posterior electrodes in response to visual feedback stimuli during shaping and random reward compared to the self-paced pressing condition where no visual feedback was provided. Furthermore, shaping was associated with a pronounced left frontal lower gamma (20-30 Hz) increase in response to feedback stimuli, whereas this pattern was not observed in the random reinforcement and self-paced pressing conditions. The present findings are in line with the notion that macroscopic high-frequency dynamics of neuronal cell assemblies may be regarded as a mechanism involved in learning and memory formation.

OBJECTIVE: The present study aimed at examining the time course and topography of oscillatory brain activity and event-related potentials (ERPs) in response to laterally presented affective pictures. METHODS: Electroencephalography was recorded from 129 electrodes in 10 healthy university students during presentation of pictures from the international affective picture system. Frequency measures and ERPs were obtained for pleasant, neutral, and unpleasant pictures. RESULTS: In accordance with previous reports, a modulation of the late positive ERP wave at parietal recording sites was found as a function of emotional arousal. Early mid gamma band activity (GBA; 30-45 Hz) at 80 ms post-stimulus was enhanced in response to aversive stimuli only, whereas the higher GBA (46-65 Hz) at 500 ms showed an enhancement of arousing, compared to neutral pictures. ERP and late gamma effects showed a pronounced right-hemisphere preponderance, but differed in terms of topographical distribution. CONCLUSIONS: Late gamma activity may represent a correlate of widespread cortical networks processing different aspects of emotionally arousing visual objects. In contrast, differences between affective categories in early gamma activity might reflect fast detection of aversive stimulus features.

Background: Schizophrenic patients exhibit more activityin the electroencephalographic delta and theta frequencyrange than do control subjects. Using magnetic sourceimaging (MSI) our study aimed to explore this phenomenonin the magnetoencephalogram (MEG), the distributionof its sources, and associations between symptomprofiles and sources of low-frequency activity in the brain.Methods: Whole-head MEG recordings were obtainedfrom 28 schizophrenic patients and 20 healthy controlsubjects during a resting condition. The generators of thefocal magnetic slow waves were located employing asingle moving dipole model. Distributed or multiple deltaand theta sources were captured by the minimum normestimate.Results: Both localization procedures showed slow waveactivity to be enhanced in schizophrenic patients comparedwith control subjects. Focal slow wave activitydiffered most between groups in frontotemporal and inposterior regions. Slow wave activity was associated withsymptom characteristics in that positive symptoms variedwith frontal delta and theta activity.Conclusions: Results indicate that activity in low-frequencybands in schizophrenic patients exceeds the activityof control subjects in distinct areas, and that this focalclustering of neuromagnetic slow waves may be related to psychopathologic characteristics.

The lifelong ability to adapt to environmental needs is based on the capacity of the central nervous system for plastic alterations. In a series of neurophysiological experiments, we studied the impact of music and musical training in musicians on the specific functional organization in auditory and somatosensory representational cortex. In one such study, subjects listened to music from which one specific spectral frequency was removed. This led to rapid and reversible adaptation of neuronal responses in auditory cortex. Further experimental evidence demonstrated that long years of practice and training by professional musicians to enable them to reach their capacity is associated with enlarged cortical representations in the somatosensory and auditory domains. This tuning of neuronal representations was specifically observed for musical tones and was absent when pure sinusoidal tones were used as stimuli. In the somatosensory cortex, plastic changes proved to be specific for the fingers frequently used and stimulated. These changes were not detected in the fingers of the hand that were not involved in playing the particular instrument. Neuroplastic alterations also may be driven into a domain where they may become maladaptive. The clinical syndrome of focal hand dystonia that may occur in musicians who engage in forceful practice may be one such consequence. We will discuss the possibilities of reversing maladaptive responses leading to the successful treatment of focal hand dystonia, which relies on basic research about cortical reorganization. This example elucidates how neuroscientific progress can guide the development of practice guidelines and therapeutic measures for the benefit of professional musicians.

Developmental dyslexia has been associated with a deficit in temporal processing, but it is controversial whether the postulated deficit is pansensory or limited to the auditory modality. We present psychophysical assessment data of auditory and visual temporal processing abilities in children with dyslexia. While none of the dyslexic children displayed temporal processing abnormalities in the visual sensory mod- ality, dyslexics with poor auditory temporal scores reached high-level visual performance. Our results do not confirm the hypothesis of a general temporal processing deficit for dyslexia but suggest that limitations in auditory temporal processing might be compensated for by a well-functioning visual sensory modality.

Magnetic brain responses recorded in the human magnetoencephalogram (MEG) distinguished between words with different semantics but carefully matched for frequency and length. Multiple recordings from a single subject showed that 100 ms following stimulus onset, significantly stronger neuromagnetic responses were elicited by words with strong multimodal semantic associations than by other word material. At this early processing step, there was a highly significant correlation (0.80) between the magnitude of brain responses to individual words recorded over parieto-occipital areas and their semantic association strengths. Subsequent to this early difference related to word meaning, additional differences in MEG responses emerged for words from different grammatical categories. Together, these results suggest that word meaning can be reflected by early neuromagnetic brain responses and before the grammatical information about the word is encoded.

BackgroundRecent field research has demonstrated that an attraction to aggressive behavior and cruelty is common among combatants and perpetrators involved in organized violence. The biological basis of this appetitive perception of aggression in humans has to date not been studied.AimsWe examined testosterone as a potential hormonal moderator during induction of specifically appetitive aggressive behavior in the laboratory.MethodTo activate physiological responding related to appetitive aggression, 145 university students (72 women) listened to tape recordings of variants of a violent story. The perspective of the listener in the story was randomized between subjects. Participants were required to either identify as perpetrator, neutral observer, or victim. We assessed changes in saliva testosterone in response to the story. Subsequently, a series of pictorial stimuli (IAPS) with different valence ratings was presented and participants determined the length of viewing time with a button click. This viewing time for negative IAPS was assessed as a dependent variable indicating level of interest in violent scenes.Results´Men identified themselves with the perpetrator more than women irrespective of the particular perspective presented by the story. Men who responded with an increase in saliva testosterone when adopting the perpetrator perspective chose to view the negative IAPS pictures for longer intervals than participants in other conditions or those who did not exhibit a release in testosterone.ConclusionsTestosterone moderates attraction to cruel and violent cues in men, as indicated by extended deliberate viewing of violence cues.

Objectives: High frequency oscillations have been suggested as a correlate of cognitive processes and have recently also been implicatedin aberrant forms of information processing. The present study investigated whether magnetoencephalographic (MEG) gamma band activity(20±71 Hz) can serve as an index of cognitive processes in the absence of external stimulation and to what extent gamma activity differsbetween healthy people and schizophrenia patients.Methods: The amount and topography of MEG power in the gamma band range was examined in 15 schizophrenia patients and 15 healthycomparison subjects while performing a complex mental arithmetic task and at rest.Results: In healthy subjects a left frontal and left fronto-temporal increase in gamma power was observed during mental arithmetic.Schizophrenia patients either failed to display such a task effect (30±45 Hz) or had reversed lateralization with enhanced activity over rightfrontal and right fronto-temporal regions under cognitive demands (45±71 Hz). In the frequency band from 60 to 71 Hz patients showed lessgamma at fronto-temporal, posterio-temporal and occipital sites irrespective of the task.Conclusions: These results indicate, Ærst, that gamma topography can index cognitive activation in a very complex and purely internaltask. Second, groups differed in the pattern of activation during the task, a result which may be consistent with working memory dysfunctionin schizophrenia. Third, the general topographic difference between healthy subjects and patients is in line with the notion of abnormalities inthe thalamocortical circuit in schizophrenia.

Abstract Reduced amplitudes of event-related potentials (ERP) have often been reported for schizophrenic patients. Positive ERPs were examined in 16 schizophrenic patients and 16 controls in a visual paired-associate learning task, in which successful learning of word pairs was evidenced by recognition of “old” versus “new” word pairs. Patients performed significantly poorer than controls. During acquisition the to-be-associated word pairs evoked a P2 and positive Slow Wave (SW) of similar amplitude in both groups. Although the recognition of items as “old” induced larger positive ERPs in controls, ERPs did not vary with recognition in patients. The presentation of the word pairs (50% old, 50% new combinations) evoked a pronounced posterior positive SW in patients but an anterior negative SW in controls. This pattern is identical to the one obtained from a previous paired-associate learning task with cue-recall and suggests that schizophrenic patients are capable of producing large amplitude positive waves under conditions different from those typical for P300 evocation in normals. The larger positive SW may indicate increased effort to compensate for deficient acquisition or association formation.

Objectives: Event-related potential correlates of phonological encoding ‐ as compared with lexical access and semantic categorization ‐ were measured in two studies involving two groups of 14 German and 14 Italian subjects. Methods: A two stimulus reaction time paradigm was used. Stimulus pairs presented one-by-one with 2 s inter-stimulus intervals (ISI) had to be matched with respect to lexical identity (word-picture) in a word comprehension task or with respect to the phonological representative of objects in a rhyming task. A semantic categorization task was added for the Italian sample. In both studies, the EEG was recorded from 26 scalp electrodes according to the 10‐20 system. The slow negative potential during the ISI (CNV) was determined as the electrocortical correlate of preparation for and activation of the specific language-related task. Results: In both samples, phonological encoding (rhyming) evoked a more pronounced CNV over the left- compared with the right-frontal area, while less lateralized central dominance of the CNV was found in the word comprehension task. Semantic categorization was accompanied by the least asymmetry of activity. Conclusions: Results indicate that the different degree of asymmetry induced by phonological and semantic processing may be determined from the scalp distribution of slow cortical potentials with cross-lingual reliability. q 2000 Elsevier Science Ireland Ltd. All rights reserved.

Maps of the body surface in somatosensory cortex have been shown to be highly plastic, altering their configuration in response to changes in use of body parts. The current study investigated alterations in the functional organization of the human somatosensory cortex resulting from massed practice. Over a period of 4 weeks, subjects were given synchronous tactile stimulation of thumb (D1) and little finger (D5) for 1 hr/d. They had to identify the orientation of the stimuli. Neuroelectric source localization based on high-resolution EEG revealed that, when subjects received passive tactile stimulation of D1 or D5, the representations of the fingers in primary somatosensory cortex were closer together after training than before. There was also an apparently correlative tendency to anomalously mislocalize near-threshold tactile stimuli equally to the distant finger costimulated during training rather than preferentially to the finger nearest to the finger stimulated in a post-training test. However, when the stimulus discrimination had to be made, neuroelectric source imaging revealed that the digital representations of D1 and D5 were further apart after training than before. Thus, the same series of prolonged repetitive stimulations produced two different opposite effects on the spatial relationship of the cortical representations of the digits, suggesting that differential activation in the same region of somatosensory cortex is specific to different tasks.

Abstract In order to determine the value of accelerometry as a measure of real world outcome when a subject is outside the laboratory, accelerometer recordings from the wrist were compared with simultaneous electromyogram (EMG) recordings from the lower and upper arm. Accelerometer and EMG signals were recorded simultaneously by the “Kölner Vitaport System,” an ambulatory device. Six male subjects performed standardized tasks as well as activities of daily life (ADL). Low correlations between accelerometer counts and integrated EMG were found in the standardized tasks, whereas there were considerably higher correlations for ADL. However, there was a strong relation between several parameters derived from EMG and accelerometer recordings. The two techniques appear to measure different aspects of movement and may be complementary.

A reliable method for the clinically useful assessment of brain structures involved in language processing would be highly desirable. Ideally, the outcome of the diagnostic procedure would show negligible dependence on the current cognitive state of a patient. To approach this goal. we studied brain activational Patterns during language processing on a rather basic level, i.e. we examined secondary processing of lexical information when words were visually presented to the subject. This condition was compared to three other experimental conditions requiring the secondary processing of non-lexical and non-verbal information in visual stimuli. The primary task for subjects was target detection. Electric and magnetic brain activity differentiated the experimental conditions starting at about 150 ms after stimulus onset. Amplitudes of components of event-related potentials and fields, as well as the similarity of magnetic field distributions between experimental conditions (as evaluated by cross-correlation) differed significantly between mainly verbal and the non-verbal conditions. This reflects presumably that secondary processing of verbal and non-verbal information in visual stimuli involves different neuroanatomical structures. Attempts to reinforce this result with source analysis techniques failed to reveal systematic effects. Possible reasons might be the inadequacy of the applied distributed source analysis model as well as interindividual variability of neuroanatomical structures involved in the processing of information.

Performance and event-related potentials (ERPs) were examined in a proactive interference (PI) task with 15 male schizophrenic patients and 15 matched healthy controls. Within a paired-associate task, 30 pairs of semantically unrelated words (A-B) were presented twice, followed by cued recall, in which the paired-associate B had to be named upon cue A. Subsequently, 50% of the A-words were paired with new words (A-C) and presented in random order together with 15 novel pairings (D-E). Slower responses and poorer recall of C- than of E-words in the final recall indicated PI in both groups. During acquisition, the paired-associates (C/E) evoked larger P3 and positive slow wave in controls than in patients. During recall, cues (A/D) evoked a slow wave with predominating anterior negativity in controls and posterior positivity in patients. The group-specific ERP pattern suggests deviant encoding and retrieval processes in schizophrenic individuals.

For the study of functional organization and reorganization of the human cortex by means of electromagnetic source imaging, a measure of the location and spatial extent of neural sources is of interest. This study evaluates the cortical patch method (CPM), an iterative procedure introduced by Lütkenhöner et al. [1995] that models EEG/MEG activity by means of extended cortical patches. Anatomical information is used to constrain estimates of location and extent of neural sources that generate the measured evoked potential. Whereas minimum norm approaches use mathematical constraints to solve the ambiguity of the inverse problem, the CPM introduces constraints based on anatomical and physiological knowledge about neural mass activity. In order to test the proposed method, the simulated activity in an artificial sulcus was subjected to the CPM. The results show that even activity on opposing walls of a sulcus can be well reconstructed. The simulations demonstrate the usefulness and limits of the CPM in estimating the spatial extent of neural sources in the cerebral cortex. As an example, an application of the method on experimental somatosensory evoked potentials is presented in the Appendix. Hum Brain Mapping 8:182–193, 1999. © 1999 Wiley‐Liss, Inc.

The time course of the event related potentials evoked within a delayed matching to sample task employing verbal and pictorial stimuli was analyzed with a source reconstruction method (miminum norm method). During signal stimulus presentation pictorial stimuli evoked more activity than verbal stimuli. Activity was particularly prominent in left frontal areas for the match of verbal–verbal stimulus pairs and over right posterior regions for the match of verbal–pictorial stimuli. Anticipation of the to-be-matched stimulus produced more pronounced activity for pictorial stimuli and generally stronger left and frontal activity. Results are discussed referring to a biological model of language processing.

We report a follow-up study on seven arm amputees in whom magnetic source imaging had originally revealed a strong correlation between the amount of cortical invasion of the deafferented cortex and the amount of pain evoked sensation mislocalized to the phantom limb. This re-examination was performed in order to corroborate the phenomenon of mislocalization. On follow-up examination for mislocalization 4 weeks later, a close correlation had remained between the original amount of cortical representational reorganization of the amputation zone (at the first examination) and the number of sites from where painful stimuli evoked sensations referred to the phantom limb, i.e. the amount of perceptual mislocalization, at the second examination. However, contrary to our expectation, the topography of referred sensation had completely changed in every patient. These results suggest that while the overall extent of reorganization is a rather stable phenomenon, the concomitant changes in the pattern of sensory processing are not. This may be due to the fact that alterations of sensory processing are not hardwired, but are rather mediated by an extensive and interconnected neural network with fluctuating synaptic strengths. This mechanism may be of importance for neurological rehabilitation.

Posttraumatic stress disorder (PTSD) is characterized by pathologic, intrusive memories of the experienced traumata. The risk to develop PTSD depends on the cumulative exposure to traumatic experience (traumatic load), on the extent of childhood adversities, and on genetic factors. The latter account for about one third of interindividual variability (1). Despite this pronounced genetic influence, little is known about the underlying genetic factors and molecular processes. Considering the strong role of fear memory development in PTSD, we recently argued for the investigation of memory-related genes in PTSD (2,3).