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Photosensitivity or photoparoxysmal response (PPR) is an electroencephalography trait that is highly associated with idiopathic generalized epilepsies (IGEs) and characterized by changes in cortical excitability in response to photic stimulation. Studying functional and structural changes of PPR might provide important insights into the pathogenesis of IGE. Recent studies revealed a functional network consisting of occipital, parietal, and precentral areas that might be implicated in PPR. Herein, we investigate the microstructural changes associated with PPR.Twelve healthy subjects with PPR, nine patients with IGE and PPR (IGE-PPR group), and 18 healthy controls were studied with diffusion magnetic resonance imaging. Tract-based spatial statistics were used to test for regional differences in fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity, and radial diffusivity between groups.Subjects with PPR exhibited higher FA in the right precentral juxtacortical white matter and higher MD in lateral occipital areas relative to controls. Patients with IGE-patients showed additional increases in regional FA in the thalamus and juxtacortical precentral and parietal areas. Both subjects with PPR and patients with IGE-PPR presented axial and radial diffusivity changes in the occipital regions.Our results show that PPR is associated with subcortical microstructural changes in precentral, parietal, and occipital regions. The coexistence of PPR and IGE is associated with white matter abnormalities in the thalamus and precuneus. PPR and epilepsy share similar functional and structural networks in widespread cortical and subcortical areas.

In the presurgical evaluation of children and juvenile patients with refractory focal epilepsy, the main challenge is to localize the point of seizure onset as precisely as possible. We compared results of the conventional electroencephalography-functional magnetic resonance imaging (EEG-fMRI) analysis with those obtained with a newly developed method using voltage maps of average interictal epileptiform discharges (IEDs) recorded during clinical long-term monitoring and with the results of the electric source imaging (ESI).Simultaneous EEG-fMRI was recorded in nine patients (ages 1.5-17.5 years) undergoing presurgical evaluation. The postoperative outcome and resected area were compared with the following: the localizations of blood oxygen-level dependent (BOLD) signal changes associated with IEDs, which were identified by visual inspection changes using SPM5 software (Analysis I); BOLD signal changes related to IED topography, which was characterized using spike-specific voltage maps of average IED recorded outside the MR scanner during clinical long-term monitoring (Analysis II); as well as results of EEG source analysis based on the distributed linear local autoregressive average (LAURA) algorithm using the Cartool software by Denis Brunet (Analysis III).All nine patients had postoperative outcome Engel class I-IIb (postoperative time 6-26 months). The analysis I revealed an IED-related area of activation within the resection area in 3 (33%) of 9 patients, analysis II was able to reliably localize the source of epileptic activity in 4 (44%) of 9 patients, and analysis III rendered results concordant with the postoperative resection site in all nine patients.The localization of seizure onset based on EEG-fMRI may be a useful adjunct in the preoperative evaluation but also has some deficits that impair the reliability of results. In contrast, EEG source analysis is clearly a more credible method for epileptic focus localization in children with refractory epilepsies. It seems likely that the analysis based on IED topography (Analysis II) may increase sensitivity and reliability of EEG-fMRI in some patients. However, the benefit from this innovative method in children is rather limited compared with adults.

„Diversity Management“ bezeichnet ein aus dem nordamerikanischen Raum stammendes Konzept zur Steigerung der Produktivitat von Arbeitsteams. Es geht von der These aus, dass man die Unterschiedlichkeit der Teammitglieder – sei es im Hinblick auf ihr Geschlecht oder ihre nationale Herkunft – nicht als Quelle von Problemen betrachten, sondern vielmehr als bereichernde Ressource wertschatzen und nutzen sollte, weil sich dies langfristig in okonomischen Gewinnen niederschlagen wurde (vgl. Bolten 2011; Kirton 2009). Praktisch vermittelt, erprobt und eingeubt wird diese Konstruktion hauptsachlich im Rahmen von Teamentwicklungsseminaren, in die sog. „Diversity-Ubungen“ eingeflochten werden.

Response cost and token approach (RCT) within the scope of a summer camp training is an effective treatment program for attention deficit hyperactivity disorder (ADHD). It is likely that intensive RCT training influences networks responsible for ADHD symptoms. Functional magnetic resonance imaging (fMRI) was carried out in 12 children with ADHD before and after the RCT program and in 12 healthy control children twice. For fMRI, a Go/No-go paradigm was used to investigate the influence of RCT training on attention and impulsivity. The No-go condition revealed only weak activation in the dorsal part of the anterior cingulate cortex (ACC), parietal and dorsolateral prefrontal cortex (DLPFC) before the training in children with ADHD compared to healthy children. However, this activation in these brain regions was significantly more pronounced after the training. This increase in hemodynamic response cannot be attributed merely to repetition of the measurement since the effect was not observed in healthy children. The increase in hemodynamic response in the ACC and right DLPFC was significantly associated with a reduction in response time variability and clinical symptoms in ADHD patients. After the RCT training, the children with ADHD demonstrated more pronounced activation of cortical structures which are typically related to response monitoring and self-control. It seems likely that children with ADHD learned more cognitive control in a continuous performance task as was revealed by both neuropsychological outcome and fMRI.

Functional MRI (fMRI) is routinely used to depict language areas, for example in the preoperative diagnostic work-up of patients with a brain tumour. The objective of this study was to test whether semantic decision making can activate the temporo-parietal language areas better than phonological generation stimuli. Five fMRI language stimuli were tested in 20 healthy volunteers: (i) word generation to a given letter (WG); (ii) verb generation to a given noun (VG); (iii) generation of groups of words (GW); (iv) detection of a semantic violation in sentences (SV); and (v) detection of pseudowords (PW). The stimuli were presented both visually and acoustically. We used a block design and evaluated the data with SPM5 with predefined regions of interest in the frontal and temporo-parietal language areas. A lateralisation index (LI) was also calculated. We found that WG and VG achieved the best results in frontal language areas; VG, SV and PW presented acoustically achieved the best results in the temporo-parietal language areas; and that LI was most reliably calculated in the frontal language areas. An acoustically presented semantic decision making stimulus should be implemented in the preoperative diagnostic work-up to robustly depict the temporo-parietal language areas. The stimulus is easy to understand and perform, and it achieves robust results.

Die Organisationsforschung geht davon aus, dass mit dem Konzept der losen Kopplung ein grundlegendes Merkmal padagogischer und sozialer Dienstleistungsorganisationen beschrieben wird (Weick 1976; Meyer/Rowan 1977; Wolff i. E.). Wenn Systemelemente lose gekoppelt sind, dann besteht zwischen ihnen eine wechselseitige Abhangigkeit, die aber insoweit reduziert ist, als dass immer eine gewisse Eigenstandigkeit und Identitat der einzelnen Elemente gewahrt bleibt. Vergleichsweise wenige formale Kontroll- und Steuerungsmechanismen sind etabliert; ihr Einsatz bedarf besonderer Anstrengungen und Bereitschaften. Lose gekoppelte Systeme werden eher durch ‚weiche‘ Mechanismen koordiniert, die nicht auf die Forcierung von Abhangigkeit, sondern eher auf die Vermeidung gegenseitiger Storung ausgelegt sind.

Generalized spike and wave discharges (GSW) are often accompanied by transitory cognitive impairment (TCI). As a possible neurophysiological correlate of TCI, activation in the thalamus and deactivation in the frontoparietal brain regions associated with GSW were discussed in previous studies which used simultaneous recordings of EEG and functional MRI (EEG-fMRI) in patients with absence epilepsy. We report on a girl having GSW up to 10 seconds without any clinical concomitants. The girl underwent an EEG-fMRI investigation with simultaneous behavioral testing (continuous performance task). Although GSW repeatedly occurred during the task, no TCI was observed. EEG-fMRI revealed bilateral deactivation in frontoparietal brain areas and activation in the thalamus in association with GSWs. This study challenges the relation between cognitive impairment during absences and the characteristic pattern of thalamic activation and deactivation in frontoparietal areas associated with GSW.

Die Beschaftigung mit institutionellen Gesprachen stellt eine konsequente Weiterentwicklung der konversationsanalytisch orientierten Diskursanalyse dar. Es geht dabei um die Untersuchung jener methodischen Prozeduren, die Gesprachsteilnehmer einsetzen, um bestimmte praktische Aufgaben zu erledigen bzw. Handlungen zu bewerkstelligen, die mit ihrer Teilnahme an institutionellen Handlungssituationen in Verbindung stehen (wie z.B. unterrichten, Krankengeschichten erheben, jemand ins Kreuzverhor nehmen, eine Prufung durchfuhren oder interviewen). Zu diesem Zweck wird eine ganze Palette linguistischer Ressourcen in den Blick genommen — lexikalische, syntaktische, prosodische, sequentielle etc. —, die von den Gesprachspartnern mobilisiert werden konnen „for accomplishing the interactional work of institutions“ (Drew/Sorjonen 1997: 92).

Der Gedanke der losen Kopplung organisatorischer Strukturelemente taucht in der organisationswissenschaftlichen Literatur ziemlich genau zur selben Zeit auf wie die vier anderen heute vorherrschenden Organisationstheorien: die Idee der evolutionaren Anpassung von Organisationen an okologische Nischen (population ecology), die These, dass die Hohe der Transaktionskosten ausschlaggebend fur die Wahl der jeweiligen Organisationsform sei (transaction cost theory), die Vorstellung, trachteten Organisationen danach, ihre Abhangigkeiten von externen Ressourcen zu minimieren bzw. fur andere wichtige Ressourcen zu kontrollieren (resource dependence theory) und die Vorstellung, dass Organisationen, um in einem gesellschaftlichen Feld bestehen zu konnen, sich an den dort institutionalisierten Vorstellungen im Hinblick auf Organisationsgestaltung und Aufgabenerfullung zu orientieren hatten (institutional theory). Orton und Weick raumen in der Ruckschau selbstkritisch ein, »each of these four perspectives has a more distinctive paradigm, a more compact theory, and more empirical support than is true of loose coupling« (1990: 203; vgl. Weick 1988), weshalb das Konzept der losen Kopplung viele Diskussionen, aber weniger Forschung ausgelost habe als vergleichbare Ansatze.

The communication of stress/anxiety between conspecifics through chemosensory signals has been documented in many vertebrates and invertebrates. Here, we investigate how chemosensory anxiety signals conveyed by the sweat of humans (N = 49) awaiting an academic examination are processed by the human brain, as compared to chemosensory control signals obtained from the same sweat donors in a sport condition. The chemosensory stimuli were pooled according to the donation condition and administered to 28 participants (14 males) synchronously to breathing via an olfactometer. The stimuli were perceived with a low intensity and accordingly only about half of the odor presentations were detected by the participants. The fMRI results (event-related design) show that chemosensory anxiety signals activate brain areas involved in the processing of social emotional stimuli (fusiform gyrus), and in the regulation of empathic feelings (insula, precuneus, cingulate cortex). In addition, neuronal activity within attentional (thalamus, dorsomedial prefrontal cortex) and emotional (cerebellum, vermis) control systems were observed. The chemosensory perception of human anxiety seems to automatically recruit empathy-related resources. Even though the participants could not attentively differentiate the chemosensory stimuli, emotional contagion seems to be effectively mediated by the olfactory system.

The assessment of sexual orientation is of importance to the diagnosis and treatment of sex offenders and paraphilic disorders. Phallometry is considered gold standard in objectifying sexual orientation, yet this measurement has been criticized because of its intrusiveness and limited reliability.To evaluate whether the spatial response pattern to sexual stimuli as revealed by a change in blood oxygen level-dependent (BOLD) signal can be used for individual classification of sexual orientation.We used a preexisting functional MRI (fMRI) data set that had been acquired in a nonclinical sample of 12 heterosexual men and 14 homosexual men. During fMRI, participants were briefly exposed to pictures of same-sex and opposite-sex genitals. Data analysis involved four steps: (i) differences in the BOLD response to female and male sexual stimuli were calculated for each subject; (ii) these contrast images were entered into a group analysis to calculate whole-brain difference maps between homosexual and heterosexual participants; (iii) a single expression value was computed for each subject expressing its correspondence to the group result; and (iv) based on these expression values, Fisher's linear discriminant analysis and the kappa-nearest neighbor classification method were used to predict the sexual orientation of each subject.Sensitivity and specificity of the two classification methods in predicting individual sexual orientation.Both classification methods performed well in predicting individual sexual orientation with a mean accuracy of85% (Fisher's linear discriminant analysis: 92% sensitivity, 85% specificity; kappa-nearest neighbor classification: 88% sensitivity, 92% specificity).Despite the small sample size, the functional response patterns of the brain to sexual stimuli contained sufficient information to predict individual sexual orientation with high accuracy. These results suggest that fMRI-based classification methods hold promise for the diagnosis of paraphilic disorders (e.g., pedophilia).

Photoparoxysmal response (PPR) is an electroencephalographic (EEG) trait characterized by the occurrence of epileptiform discharges in response to visual stimulation. Studying this trait helps to learn about mechanisms of epileptogenicity. While simultaneous recordings of EEG and functional MRI (EEG-fMRI) in patients with spontaneous generalised spike-wave discharges (GSW) have revealed activation of the thalamus and deactivation in frontoparietal areas, EEG-fMRI studies on evoked GSW such as PPR are lacking. In this EEG-fMRI study, 30 subjects with reported generalised PPR underwent intermittent photic stimulation (IPS) in a 3 T MR scanner. PPR was elicited in 6 subjects, four diagnosed with idiopathic generalised epilepsy and two with tension-type headache. Because PPR is preceded by synchronization of cortical gamma oscillations, blood oxygenation level-dependent (BOLD) signal changes were analysed at the onset of the PPR (standard regressor) and 3 s before the onset of PPR (early regressor) in one model. In all subjects, IPS led to a significant activation of the visual cortex. Based on the early regressor, PPR associated activation was found in the parietal cortex adjacent to the intraparietal sulcus in five and in the premotor cortex in all 6 subjects. The standard regressor revealed deactivation in early activated areas in all subjects and thalamic activation in one subject. In contrast to spontaneous GSW, these results suggest that PPR is a cortical phenomenon with an involvement of the parietal and frontal cortices. Pronounced haemodynamic changes seen with the early regressor could mirror gamma activity that is known to precede PPR.

When the bladder is fairly full, the desire to void can be suppressed, but it can also be called forth deliberately. We studied brain activity during such intentional modulations of bladder sensation in 33 healthy volunteers (17 women, 16 men). The supplementary motor area, midcingulate cortex, insula, frontal operculum, and right prefrontal cortex were consistently more active when the desire to void was enhanced without allowing urine to pass ("attempted micturition") than during a baseline task when bladder sensations were suppressed. The right anterior insula and midbrain periaquaeductal grey (PAG) were more active at higher than at lower bladder volumes. Responses of the right thalamus and several other right-hemispherical regions were stronger in women than in men. Using the psychophysiological interaction (PPI) method, we found that the midcingulate cortex had stronger connectivity (indicated by parallel co-variations of the activation time series) with the PAG and medial motor areas during "attempted micturition" than during the baseline task, possibly reflecting monitoring of urethral sphincter contractions. Conversely, the left and right insula showed decreased connectivity with many other brain regions during "attempted micturition", possibly due to predominant processing of bladder-afferent input. Intentional modulations of the desire to void change the effective connectivity of supraspinal regions involved in bladder control.

Summary Purpose: In patients with idiopathic generalized epilepsy (IGE), blood oxygen level dependent (BOLD) EEG during functional MRI (EEG-fMRI) has been successfully used to link changes in regional neuronal activity to the occurrence of generalized spike-and-wave (GSW) discharges. Most EEG-fMRI studies have been performed on adult patients with long-standing epilepsy who were on antiepileptic medication. Here, we applied EEG-fMRI to investigate BOLD signal changes during absence seizures in children with newly diagnosed childhood absence epilepsy (CAE). Methods: Ten drug-naive children with newly diagnosed CAE underwent simultaneous EEG-fMRI. BOLD signal changes associated with ictal EEG activity (i.e., periods of three per second GSW) were analyzed in predefined regions-of-interests (ROIs), including the thalamus, the precuneus, and caudate nucleus. Results: In 6 out of 10 children, EEG recordings showed periods of three per second GSW during fMRI. Three per second GSW were associated with regional BOLD signal decreases in parietal areas, precuneus, and caudate nucleus along with a bilateral increase in the BOLD signal in the medial thalamus. Taking into account the normal delay in the hemodynamic response, temporal analysis showed that the onset of BOLD signal changes coincided with the onset of GSW. Discussion: In drug-naive individuals with CAE, ictal three per second GSW are associated with BOLD signal changes in the same striato-thalamo-cortical network that changes its regional activity during primary and secondary generalized paroxysms in treated adults. No BOLD signal changes in the striato-thalamo-cortical network preceded the onset of three per second GSW in unmediated children with CAE.

The aim of this study was to establish if patients with hemodynamically relevant or irrelevant stenoses of the extracranial internal carotid artery have different intracranial arterial oxygen saturation as measured by transcranial pulse oximetry using near infrared spectroscopy.

Zusammenfassung Das Problem der Sicherstellung von Tatsächlichkeit in psychiatrischen Gerichtsgutachten wird aus einer ethnomethodologischen Perspektive empirisch untersucht. Dabei zeigt sich, daß sich Tatsächlichkeit für Gutachter in erster Linie als ein auf der Textebene zu bewältigendes Problem darstellt. Zu dessen Lösung werden vorwiegend Autoristerungen eingesetzt, die in gleicher Weise auch im gesellschaftlichen Alltag Verwendung finden. Dieses Ergebnis wirft ein neues Licht auf die vielfältigen Bemühungen um Objektivierung und Verwissenschaftlichung von Gutachten.

Handgrips can be broadly classified into precision and power grips. To compare central neuronal control of these tasks, functional magnetic resonance imaging was used in 14 healthy right-handed volunteers, who repetitively squeezed non-flexible force transducers with a precision grip and a power grip of the dominant hand. The relative grip force levels and movement rates (0.45 Hertz) of both tasks were comparable. Peak isometric grip forces ranged between 1% and 10% of the maximum voluntary force. Reflecting the additional recruitment of extrinsic hand muscles and the higher absolute force, activation of the contralateral primary sensorimotor cortex (M1/S1) and ipsilateral cerebellum was significantly stronger during power than during precision grip. No brain areas exhibited stronger activity during the precision grip than during the power grip. The left M1/S1 and right cerebellum showed a positive linear relationship with the grip force, while the right angular gyrus and left superior frontal gyrus showed a gradual increase in activity when less force was applied. However, these force-dependent modulations of brain activity were similar for the precision and power grip tasks. No brain region was specifically activated during one task but not during the other. Activity during precision gripping did not exceed the activity associated with power gripping possibly because the precision grip task was not challenging enough to call on dexterous fine motor control.

Although negative blood oxygen level-dependent (BOLD) signal changes are very frequent findings in neuroimaging studies of neuronal networks underlying interictal epileptiform discharges (IEDs), the nature of negative BOLD effects in epilepsy remains unclear. To investigate the influence of sleep on BOLD responses to internal activity such as IED, hemodynamic changes associated with IED were analysed in sleep stages 1 and 2 in four children with focal epilepsies who underwent simultaneous EEG–fMRI recordings. There were significantly more voxels with negative BOLD responses and better fit of the expected with the real course of BOLD signal for the negative BOLD effect in sleep stage 2 compared to stage 1. Moreover, the increase in omega (12.0–14.0 Hz) and delta (0.5–4.0 Hz) power correlated with an increase in the number of deactivated voxels. This study indicates that the second stage of sleep seems to be associated with an increase in negative BOLD response to internal activity compared with sleep stage 1. An increase in inhibitory influences during sleep and decrease of sleep-associated, energy-consuming processes may be responsible for the described negative BOLD signal changes.

Is sexual orientation associated with structural differences in the brain? To address this question, 80 homosexual and heterosexual men and women (16 homosexual men and 15 homosexual women) underwent structural MRI. We used voxel-based morphometry to test for differences in grey matter concentration associated with gender and sexual orientation. Compared with heterosexual women, homosexual women displayed less grey matter bilaterally in the temporo-basal cortex, ventral cerebellum, and left ventral premotor cortex. The relative decrease in grey matter was most prominent in the left perirhinal cortex. The left perirhinal area also showed less grey matter in heterosexual men than in heterosexual women. Thus, in homosexual women, the perirhinal cortex grey matter displayed a more male-like structural pattern. This is in accordance with previous research that revealed signs of sex-atypical prenatal androgenization in homosexual women, but not in homosexual men. The relevance of the perirhinal area for high order multimodal (olfactory and visual) object, social, and sexual processing is discussed.

Summary Purpose: West syndrome is a severe epileptic encephalopathy of infancy characterized by a poor developmental outcome and hypsarrhythmia. The pathogenesis of hypsarrhythmia is insufficiently understood. Methods: We investigated eight patients with infantile spasms and hypsarrhythmia (group I) and 8 children with complex partial seizures (group II) using simultaneous recordings of electroencephalogram (EEG) and functional MRI. Hemodynamic responses to epileptiform discharges and slow wave activity (EEG delta power) were analyzed separately. Results: In group I (mean age, 7.82 ± 2.87 months), interictal spikes within the hypsarrhythmia were associated with positive blood oxygenation level-dependent (BOLD) changes in the cerebral cortex (especially occipital areas). This was comparable with cortical positive BOLD responses in group II (mean age, 20.75 ± 12.52 months). Slow wave activity in group I correlated significantly with BOLD signal in voxels, which were localized in brainstem, thalamus, as well as different cortical areas. There was no association between BOLD effect and EEG delta power in group II. Moreover, as revealed by group analysis, group I differed from group II according to correlations between BOLD signal and slow wave activity in putamen and brainstem. Conclusions: This study demonstrates that multifocal interictal spikes and high-amplitude slow wave activity within the hypsarrhythmia are associated with the activation of different neuronal networks. Although spikes caused a cortical activation pattern similar to that in focal epilepsies, slow wave activity produced a hypsarrhythmia-specific activation in cortex and subcortical structures such as brainstem, thalamus, and putamen.

The pathophysiology of generalized spike wave discharges (GSW) is not completely understood. Thalamus, basal ganglia and neocortex have been implicated in the generation of GSW, yet the specific role of each structure remains to be clarified. In six children with idiopathic generalized epilepsy (IGE), we performed combined EEG-fMRI to identify GSW-related changes in blood oxygen level-dependent (BOLD) signal in the striato-thalamo-cortical network. In all patients, within-subject analysis demonstrated BOLD signal changes that preceded the GSW. An increase in BOLD signal in the medial thalamus started 6 s before the onset of the GSW. Decreases in cortical BOLD signal were mainly found in frontoparietal areas and precuneus starting 6 to 3 s before the GSW. All patients showed a decrease in BOLD signal in the head of the caudate nucleus with a variable onset. The temporospatial pattern of BOLD signal changes suggests that GSW on the cortical surface is preceded by a sequence of neuronal events in the thalamo-cortical-striatal network. Approximately 6 s before the GSW, the thalamus shows an increase in neuronal activity along with regional decreases in cortical activity. These changes in thalamo-cortical activity are followed by a deactivation of the caudate nucleus. These early changes in BOLD signal may reflect changes in neuronal activity that contribute to the generation of GSW and may contribute to the transition from a normal to a generalized hypersynchronous pattern of neuronal activity. Our preliminary findings warrant further studies on a larger number of patients to explore the influence of age, medication and type of epileptic syndrome.

Fragestellung: Die pathophysiologische Bedeutung des Kleinhirns beim klassischen essentiellen Tremor (ET) wurde anhand klinischer, elektrophysiologischer und funktionell-bildgebender Verfahren belegt. Unklar ist derzeit, ob die cerebellare Dysfunktion auch mit subtilen strukturellen Auffalligkeiten des cortico-cerebello-thlamischen Symstems assoziiert ist. Methoden: Wir fuhrten eine voxelbasierte Morphometrie (VBM) der grauen und weisen Hirnsubstanz basierend auf hochauflosenden T1-gewichteten MRT-Sequenzen durch. Untersucht wurden 27 Patienten mit ET und 27 in Alter und Geschlecht vergleichbare Kontrollpersonen. Unter den ET-Patienten befanden sich 14 Patienten mit einem posturalen Tremor und 13 Patienten mit einem zusatzlichen Intentionstremor. Ergebnisse: Es liesen sich keine signifikanten Unterschiede in der Dichte der grauen und weisen Substanz zwischen ET-Patienten und Kontrollpersonen nachweisen. Dieses galt auch, wenn die ET-Untergruppen (mit und ohne Intentionstremor) separat mit den entsprechenden Kontrollpersonen verglichen wurden. Der Vergleich beider Patientenuntergruppen jedoch zeigte bei ET-Patienten mit Intentionstremor eine relative Zunahme in der Dichte der grauen Substanz beiderseits im Bereich des temporoparietalen Ubergangs und des rechten Gyrus occipitalis medialis. Schlussfolgerungen: Es ergab sich kein Hinweis auf einen neurodegenerativen Prozess als Ursache des ET. Patienten mit Intentionstremor zeigen eine relative Vermehrung der grauen Substanz in Hirnarealen, die in visuell-raumliche Verarbeitungsprozesse involviert sind, wobei es sich hier um eine ausbleibende physiologische Volumenabnahme im Alter zu handeln scheint. Diese lokal ausbleibende Hirnatrophie ware als adaptive Reorganisation bei langfristiger hoher Beanspruchung der fur die visuell-raumliche Kontrolle zielgerichteter Bewegungen zustandigen Systeme durch den Tremor zu sehen.

Fragestellung: West-Syndrom stellt ein diagnostisches und therapeutisches Problem in der padiatrischen Epileptologie dar. Die Mechanismen dieses Krankheitsbildes, mit Blitz-Nick-Salaam-Anfallen, Hypsarrhythmie im EEG und Entwicklungsverzogerung, sind unbekannt. Die Hypsarrhythmie besteht aus zwei elektrophysiologischen Phanomenen: multifokaler hypersynchroner Aktivitat (HSA) und langsamer Aktivitat (hochamplitudige Delta-Paroxysmen). Die neuronalen Netzwerke, die der beiden Phanomene zugrunde liegen, wurden in dieser Studie untersucht. Methoden: 10 Kinder mit West-Syndrom (1,4±1,2 Jahre) und 10 gleichaltrige Kinder mit fokalen Epilepsien (1,8±1,9 Jahre) wurden mittels simultaner Aufnahmen von EEG (MR-kompatibles BrainVision-System® mit 30 Ag/AgCl-Elektroden) und fMRI (Philips Achieva 3-Tesla Scanner, EPI-Sequenzen mit TR=2,25 Sek, 64×64 Matrix, 540 Dynamiken uber 20 Min) untersucht. HSA wurde manuell markiert und als Regressor benutzt. Langsame Delta-Aktivitat wurde mittels FFT alle 2,25 Sek evaluiert und als ein parametrischer Regressor in die SPM5-Analyse einbezogen. EPI-Bilder von Kindern ohne grose Lasionen wurden normalisiert und beide Gruppen miteinander verglichen (Random Effect-Gruppenanalyse). Das Signifikanzniveau wurde FDR-korrigiert. Ergebnisse: Die HSA war mit Arealen signifikanter Aktivierung im zerebralen Kortex assoziiert, wobei bei allen Kindern ein positiver BOLD-Effekt in den okzipitalen, bei 90% in den parietalen und bei 70% in den frontalen Kortices auftrat. Nur zwei Kinder wiesen eine subkortikale Aktivierung auf. Die langsame Aktivitat jedoch (Delta-Power) korrelierte signifikant mit dem positiven BOLD-Effekt bei allen Kindern im Hirnstamm (Pons), bei 70% im Thalamus beidseits, bei 40% in den Basalganglien sowie bei allen Kindern in unterschiedlichen Arealen des Kortex. Die Gruppenanalyse ergab eine, verglichen mit Kindern mit anderen Epilepsien, signifikante Aktivierung im Putamen und Globus pallidus beidseits, die assoziiert war mit der langsamen Hirnaktivitat im EEG. Schlussfolgerungen: Die Studie zeigte, dass die HSA mit einer multifokalen Aktivierung der kortikalen Areale und die langsame Aktivitat mit einer Aktivierung subkortikaler Strukturen assoziiert ist. Ubereinstimmend mit vorangegangenen PET-Studien sind die Kinder mit West-Syndrom auch durch Aktivierung von Putamen und Globus pallidus charakterisiert. Die Ergebnisse weisen auf eine besondere Bedeutung von Delta-Aktivitat in der Pathogenese des West-Syndroms hin.

Fragestellung: Die Ursachen des negativen BOLD-Effektes in EEG-fMRI-Studien bei Epilepsie sind unklar. In unserer vorangegangenen Studie konnten wir zeigen, dass die hypersynchrone Aktivitat bei Kindern mit Epilepsie besonders haufig mit einem negativen BOLD-Effekt assoziiert ist (Jacobs et al., Human Brain Mapping, eingereicht). Da die Kinder in unseren Studien im Schlaf untersucht werden, kann man vermuten, dass Schlaf einen Einfluss auf die BOLD-Antwort hat. Methoden: Von 120 Kindern mit Epilepsie, die mittels simultaner Aufnahmen von EEG (MR-kompatibles BrainVision-System® mit 30 Ag/AgCl-Elektroden) und fMRI (Philips Achieva 3-Tesla Scanner, EPI-Sequenzen mit TR=2,25 Sek, 64×64 Matrix, 540 Dynamiken uber 20 Min) untersucht worden sind, zeigten 5 Kinder (fokale Epielpsien, Alter: 9,2±4,6 Jahre) einen Wechsel von Schlafstadium I und Schlafstadium II. Die Markierung von Schlafstadien erfolgte gemas der internationalen Kriterien (Rechtschaffen & Kales, 1968). Die Markierung von Sharp-Wave-Komplexen im EEG wurde manuell durchgefuhrt. Die Anzahl von aktivierten bzw. deaktivierten Voxel sowie die Hohe der maximalen t-Werte fur jeden Cluster wurde zwischen Schlafstadium I und II mittels Wilcoxon-Test verglichen. Ergebnisse: Der Sharp-wave-assoziierte positive BOLD-Effekt zeigte keinen signifikanten Unterschied zwischen dem Schlafstadium I und II in Bezug auf alle untersuchten abhangigen Variablen. Der negative BOLD-Effekt stieg im II. Schlafstadium an. Wir fanden eine signifikante Erhohung sowohl der Anzahl der deaktivierten Voxel (Stadium I: 126,9±266; Stadium II: 658,9±568; Z=–2,197; P=0,02) als auch der maximalen t-Werte in Clustern (Stadium I: 5,15±1,53; Stadium II: 6,98±1,86; Z=–1,99; P=0,04). Schlussfolgerungen: Ubereinstimmend mit vorangegangenen Studien, die einen deutlichen Anstieg des negativen BOLD-Effektes auf akustische und visuelle Stimulation wahrend des Schlafs gezeigt haben (Born et al., 2002; Czisch et al., 2004), verursacht der Wechsel vom I. zum II. Schlafstadium auch bei hypersynchroner epileptischer Aktivitat eine Erhohung der negativen BOLD-Antwort. Damit konnen haufige Deaktivierungen bei Kindern mit Epilepsie teilweise auf den Einfluss von Schlaf auf die BOLD-Antwort zuruckgefuhrt werden.

Market research focus groups generate three types of data: first, representatives of commissioning companies or organizations watch the group from behind a one-way mirror; second, they receive a video of the group discussion; third, they are given a report of the focus group. This article analyses how the required data are interactionally produced to be visible for the people behind the one-way screen, for the video and for the report. It describes the phenomenon of repeat receipts as a central device for producing visible data. Repeat receipts are sequences where the moderator repeats participants’contributions, typically with intonational cues that mark completion. Repeat receipts have several functions. They can (a) highlight central market-research relevant terms from participants’responses; (b) strip off rhetorical relations by repeating utterances in a decontextualized manner; (c) summarize contributions in repeating contributions of different authors as if of one voice; (d) cover conflict in repeating potentially contradictory contributions as discrete statements; (e) socialize responding by providing templates for the required contributions. Repeat receipts help shape the focus group interaction to generate visible data for the overhearing audience, the video and the report. The article ends with a comparison of repeats in market research focus groups, standardized surveys and news interviews. Market research focus groups generate three types of data: first, representatives of commissioning companies or organizations watch the group from behind a one-way mirror; second, they receive a video of the group discussion; third, they are given a report of the focus group. This article analyses how the required data are interactionally produced to be visible for the people behind the one-way screen, for the video and for the report. It describes the phenomenon of repeat receipts as a central device for producing visible data. Repeat receipts are sequences where the moderator repeats participants’contributions, typically with intonational cues that mark completion. Repeat receipts have several functions. They can (a) highlight central market-research relevant terms from participants’responses; (b) strip off rhetorical relations by repeating utterances in a decontextualized manner; (c) summarize contributions in repeating contributions of different authors as if of one voice; (d) cover conflict in repeating potentially contradictory contributions as discrete statements; (e) socialize responding by providing templates for the required contributions. Repeat receipts help shape the focus group interaction to generate visible data for the overhearing audience, the video and the report. The article ends with a comparison of repeats in market research focus groups, standardized surveys and news interviews.