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Aim: The aim of this study was to investigate whether magnetoencephalographic oscillations underlying working memory dysfunction in the dorsolateral prefrontal cortex (DLPFC) are related to psychopathological disturbance in patients with schizophrenia-like psychosis of epilepsy (SLPE)., Methods:   Twelve patients with SLPE and 14 non-psychotic epilepsy controls participated in this study. Magnetoencephalography was recorded while patients performed a visual working memory (WM) task. Psychopathology was assessed using a four-factor structure of the Brief Psychiatric Rating Scale, and regression analyses were carried out to examine the relative impact of severity of psychopathology on WM-induced activation of the DLPFC., Results: We found that activation of the WM-compromising DLPFC, as indicated by increased alpha desynchronization in patients with SLPE compared with their non-psychotic counterparts, showed a positive linear correlation with disorganization symptom scores. This association remained significant after controlling for confounding factors, including age, task performance, IQ, and duration of psychosis., Conclusion: Our results indicate that abnormal activation in prefrontal areas engaged during working memory may be critical to domains of psychopathology, in particular disorganized thought-processing in patients with SLPE., (© 2011 The Authors. Psychiatry and Clinical Neurosciences © 2011 Japanese Society of Psychiatry and Neurology.)

Background: It is unclear whether, like in schizophrenia, psychosis-related disruption in connectivity between certain regions, as an index of intrinsic functional disintegration, occurs in schizophrenia-like psychosis of epilepsy (SLPE). In this study, we sought to determine abnormal patterns of resting-state EEG oscillations and functional connectivity in patients with SLPE, compared with nonpsychotic epilepsy patients, and to assess correlations with psychopathological deficits., Methodology/principal Findings: Resting EEG was recorded in 21 patients with focal epilepsy and SLPE and in 21 clinically-matched non-psychotic epilepsy controls. Source current density and functional connectivity were determined using eLORETA software. For connectivity analysis, a novel nonlinear connectivity measure called "lagged phase synchronization" was used. We found increased theta oscillations in regions involved in the default mode network (DMN), namely the medial and lateral parietal cortex bilaterally in the psychotic patients relative to their nonpsychotic counterparts. In addition, patients with psychosis had increased beta temporo-prefrontal connectivity in the hemisphere with predominant seizure focus. This functional connectivity in temporo-prefrontal circuits correlated with positive symptoms. Additionally, there was increased interhemispheric phase synchronization between the auditory cortex of the affected temporal lobe and the Broca's area correlating with auditory hallucination scores., Conclusions/significance: In addition to dysfunction of parietal regions that are part of the DMN, resting-state disrupted connectivity of the medial temporal cortex with prefrontal areas that are either involved in the DMN or implicated in psychopathological dysfunction may be critical to schizophrenia-like psychosis, especially in individuals with temporal lobe epilepsy. This suggests that DMN deficits might be a core neurobiological feature of the disorder, and that abnormalities in theta oscillations and beta phase synchronization represent the underlying neural activity.

Working memory (WM) deficits are considered a core cognitive dysfunction in schizophrenia. To determine cognitive abnormalities in chronic interictal psychosis (CIP), and to assess whether these abnormalities are distinguishable from those seen in schizophrenia in terms of WM deficits, we used magnetoencephalography during a WM task performed by patients with CIP, nonpsychotic epilepsy, and schizophrenia and by healthy subjects. Multiple Source Beamformer and Brain-Voyager were used for analysis. In both patients with CIP and those with schizophrenia, we found dorsolateral prefrontal hyperactivation and left inferior temporal hypoactivation, as indicated by alpha event-related desynchronization and synchronization, respectively. Patients with schizophrenia also showed alpha2 event-related desynchronization in the mid-prefrontal cortex relative to healthy controls. Direct comparison of patients with CIP and schizophrenia rendered no difference in source-power changes. Our findings indicate similar functional cognitive abnormalities in CIP and schizophrenia in the prefrontal and left temporal cortex, which supports the possibility that these disorders share common underlying pathophysiological mechanisms., (2009 Elsevier Inc. All rights reserved.)

The purpose of this study is to weigh psychological state, patients' demographics, seizure-related factors, and medical comorbidity in older adults with epilepsy against the same parameters in younger adults in an attempt to identify best quality of life (QoL) predictors. The Quality of Life in Epilepsy Inventory for Adults (QOLIE-31) and the Beck Depression Inventory-II (BDI-II) were completed by 146 patients with localization-related epilepsy. There was no statistical difference in the QOLIE-31 total score between younger and older adults. Best QoL predictors were BDI-II and seizure frequency, with BDI-II providing more than 3 times the impact of seizure frequency. BDI-II also substantively predicted most QOLIE-31 domains. Additionally, epilepsy duration positively correlated with overall QoL only among older adults. In summary, in younger as well as older adult epilepsy patients, depressive symptoms emerge as the strongest predictor of QoL. However, older adults appear to adapt better to their chronic health problem.

The hallmark of tuberous sclerosis is the presence of multiple cortical tubers. Identifying the epileptogenic tubers is difficult and often requires invasive intracranial electroencephalograph (EEG) monitoring. We report on a patient with tuberous sclerosis upon whom the novel magnetoencephalography (MEG) technique of synthetic aperture magnetometry (SAM) with excess kurtosis (g2) analysis was performed for localization of the epileptogenic tuber. Simultaneous electroencephalography (EEG) was also performed. MEG data, as analyzed by SAM(g2), were superimposed on the patient's MRIs. In the fluid attenuated inversion recovery MRIs, several tubers and subependymal nodules could be identified, with the largest tubers being located in the right frontal and left anteriotemporal regions. Despite multiple cortical lesions existing, the SAM(g2) images showed a single large tuber and surrounding epileptogenic tissue in the left temporal cortex. We suggest that MEG with SAM(g2) analysis may be clinically useful for the accurate identification of epileptogenic tubers in patients with tuberous sclerosis.

Although a nonspecific cephalic sensation, the so-called "cephalic aura," is a common sensory aura, particularly in frontal lobe seizures, but is rarely is the entire sensory seizure event. The unusual presentation of cephalic sensations in isolation representing supplementary motor area (SMA) seizures, which are commonly unaccompanied by ictal electroencephalography (EEG) changes, can easily lead to misdiagnosis of nonepileptic psychogenic seizures. We illustrate the case of a 36-year-old male patient with frontal lobe epilepsy who presented with isolated cephalic auras described as a nonvertiginous sense of head movement without observable clinical signs after his habitual partial motor seizures were controlled with pharmacotherapy. Video/EEG recordings showed no recognizable epileptic discharges time-locked to the onset of the isolated cephalic auras. Ictal magnetoencephalography (MEG) with synthetic aperture magnetometry-kurtosis (SAM(g(2))) analysis demonstrated the SMA onset of the cephalic auras; thus, MEG was essential in differentiating these isolated auras from nonepileptic psychogenic events.