Neural correlates of reality filtering in schizophrenia spectrum disorder.

BACKGROUND: A false sense of reality is a characteristic of schizophrenia spectrum disorders (SSD). Reality confusion may also emanate from posterior orbitofrontal cortex (OFC) lesions, as evident in confabulations that patients act upon and disorientation. This confusion can be measured by repeated runs of a continuous recognition task (CRT): patients increase their false positive rate from the second run on, failing to realize that an item is not a repetition within the current run. Correct handling of these stimuli, a faculty called orbitofrontal reality filtering (ORFi), induces a distinct frontal potential at 200-300 ms, the "ORFi potential". Patients with schizophrenia have been reported to fail in this task, too. Here, we explored the electrophysiology of ORFi in SSD. METHODS: Evoked potentials, source, and connectivity analyses derived from high-density electroencephalograms of 17 patients with SSD and 15 age-matched healthy controls performing two runs of a CRT. RESULTS: Although the patients obtained normal performance, they did not normally express the frontal potential typical of ORFi between 200 and 300 ms. Coherence analysis demonstrated virtually absent functional connectivity in the theta band within the memory network in this period. Source analysis showed increased activity in left medial temporal and prefrontal regions in patients. CONCLUSIONS: SSD patients appear to invoke compensatory resources to handle the challenges of reality filtering. An abnormal ORFi potential may be an early biomarker of SSD.

A New Perspective on Delusional States - Evidence for Claustrum Involvement.

Delusions are a hallmark positive symptom of schizophrenia, although they are also associated with a wide variety of other psychiatric and neurological disorders. The heterogeneity of clinical presentation and underlying disease, along with a lack of experimental animal models, make delusions exceptionally difficult to study in isolation, either in schizophrenia or other diseases. To date, no detailed studies have focused specifically on the neural mechanisms of delusion, although some studies have reported characteristic activation of specific brain areas or networks associated with them. Here, we present a novel hypothesis and extant supporting evidence implicating the claustrum, a relatively poorly understood forebrain nucleus, as a potential common center for delusional states.

Oncological patterns of care and outcome for 952 patients with newly diagnosed glioblastoma in 2004.

This report, an audit requested by the French government, describes oncological patterns of care, prognostic factors, and survival for patients with newly diagnosed and histologically confirmed glioblastoma multiforme (GBM) in France. The French Brain Tumor DataBase, which is a national multidisciplinary (neurosurgeons, neuropathologists, radiotherapists, neurooncologists, epidemiologists, and biostatisticians) network, prospectively collected initial data for the cases of GBM in 2004, and a specific data card was used to retrospectively collect data on the management and follow-up care of these patients between January 1, 2004, and December 1, 2006. We recorded 952 cases of GBM (male/female ratio 1.6, median age 63.9 years, mean preoperative Karnofsky performance status [KPS] 79). Surgery consisted of resection (RS; n = 541) and biopsy (n = 411); 180 patients did not have subsequent oncological treatment. After surgery, first-line treatment (n = 772) consisted of radiotherapy (RT) and temozolomide (TMZ) concomitant +/- adjuvant in 314 patients, RT alone in 236 patients, chemotherapy (CT) alone in 157 patients, and other treatment modalities in 65 patients. Median overall survival was 286 days (95% CI, 266-314) and was significantly affected by age, KPS, and tumor location. Median survival (days, 95% CI) associated with these main strategies, when analyzed by a surgical group, were as follows: RS + RT-TMZ((n=224)): 476 (441-506), biopsy + RT-TMZ((n=90)): 329 (301-413), RS + RT((n=147)): 363 (331-431), biopsy + RT((n=89)): 178 (153-237), RS + CT((n=61)): 245 (190-361), biopsy + CT((n=96)): 244 (198-280), and biopsy only((n=118)): 55 (46-71). This study illustrates the usefulness of a national brain tumor database. To our knowledge, this work is the largest report of recent GBM management in Europe.