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Verb generation is among the most frequently used tasks in presurgical mapping. Because this task involves many processes, the overall brain effects are not specific. While it is necessary to identify the whole network involving noun comprehension or semantic retrieval and lexical selection to produce the verb, isolation of those components is also crucial. Here, we present data from four patients undergoing presurgical brain mapping. The study implied a reanalysis of magnetoencephalography data with a recategorization of the used items. It aimed to extract the task component that relies on the inferior frontal gyrus (IFG). The task could be applied with higher specificity when targeting frontal areas. For that, we based item classification on the selection demands imposed by the noun. It is a robust finding that the IFG carries out this selection and that a quantitative index can be calculated for each noun, which depends on the selection effort (Proceedings of the National Academy of Sciences of the United States of America, 1997; 94(26):14792–14797, Proceedings of the National Academy of Sciences of the United States of America, 1998; 95(26):15855–15860). Data showed focality and specificity, with a correlation between this derived index and source activations in the inferior frontal gyrus for all patients. Strikingly, we detected when the right‐hemisphere homologue area was involved in the selection process in two patients showing reorganization or language right lateralization. The present data are a step towards a dissection of broad specific tasks frequently used in presurgical protocols. [ABSTRACT FROM AUTHOR]

All electrostimulation studies on arithmetic have so far solely reported general errors. Nonetheless, a classification of the errors during stimulation can inform us about underlying arithmetic processes. The present electrostimulation study was performed in a case of left parietal glioma. The patient's erroneous responses suggested that calculation was mainly applied for addition and a combination of retrieval and calculation was mainly applied for multiplication. The findings of the present single-case study encourage follow up with further data collection with the same paradigm. [ABSTRACT FROM AUTHOR]

The article discusses the balance between the lexical and sublexical pathways of dual-route of reading. It cites on the complexity of reading ability which motivated neuropsychological models. The article also discusses the research that focused on reading abilities in a small series of patients operated in an awake conditions for a diffuse low-grade glioma of the posterior temporo-basal region.

Previous behavioural studies in Spanish have found a significant preference for attaching relative clauses preceded by a complex NP (N1 of N2 RC) to the first noun phrase. In the present study, we used event-related potentials (ERPs) to help identify the nature of these processes by directly comparing ERPs to temporary ambiguous sentences containing relative clauses that were finally consistent with either high or low attachment resolution. The larger amplitude of the P600 effect for the low attachment condition suggests that high attachment was the preferred strategy. The P600 effect was widely distributed in the 500-700 ms window, including frontal areas, while the distribution was mainly posterior in the 700-1000 ms window. The results indicate that high attachment is the parsing strategy Spanish readers use for this type of ambiguity and suggest that the P600 may not be a monolithic effect., (Copyright 2004 Elsevier B.V.)