Functional human brain mapping is commonly performed during invasive monitoring with intracranial electroencephalographic electrodes prior to resective surgery for drug­ resistant epilepsy. The current gold standard, electrocortical stimulation mapping, is time ­consuming, sometimes elicits pain, and often induces after discharges or seizures. Moreover, there is a risk of overestimating eloquent areas due to propagation of the effects of stimulation to a broader network of language cortex. Passive iEEG spatial-temporal functional mapping has recently emerged as a potential alternative to ESM. However, (...) investigators have observed less correspondence between STFM and ESM maps of language than between their maps of motor function. We hypothesized that incongruities between ESM and STFM of language function may arise due to propagation of the effects of ESM to cortical areas having strong effective connectivity with the site of stimulation. We evaluated five patients who underwent invasive monitoring for seizure localization, whose language areas were identified using ESM. All patients performed a battery of language tasks during passive iEEG recordings. To estimate the effective connectivity of stimulation sites with a broader network of task-activated cortical sites, we measured cortico-cortical evoked potentials elicited across all recording sites by single-pulse electrical stimulation at sites where ESM was performed at other times. With the combination of high gamma power as well as CCEPs results, we trained a logistic regression model to predict ESM results at individual electrode pairs. The average accuracy of the classifier using both STFM and CCEPs results combined was 87.7%, significantly higher than the one using STFM alone, indicating that the correspondence between STFM and ESM results is greater when effective connectivity between ESM stimulation sites and task-activated sites is taken into consideration. These findings, though based on a small number of subjects to date, provide preliminary support for the hypothesis that incongruities between ESM and STFM may arise in part from propagation of stimulation effects to a broader network of cortical language sites activated by language tasks, and suggest that more studies, with larger numbers of patients, are needed to understand the utility of both mapping techniques in clinical practice. (shrink)

The precise relationship between Hobbes's political philosophy and his late history of the English Civil War remains something of a puzzle. Given his well known doubts about the epistemological status of history, Behemoth or the Long Parliament is often treated as little more than a procrustean effort at forcing complex historical events into the bed of abstract theory that he had developed earlier. On this view, even Noam Flinker, who offers one of the few studies devoted to a close (...) reading of Behemoth, argues that Hobbes intended the work to be self repudiating, and that the dialogue form and the apparent confusions of one of the participants were meant to point readers to �the less rhetorical logic of the Leviathan�. Others, more impressed by Hobbes�s pragmatic intentions than his methodological pretensions, note that a primary motive for his political arguments was a horror at first of the prospect and then of the reality of civil war. They thus emphasize the significance of Behemoth for Hobbes and his interpreters. Robert Kraynak, for example, argues that it �is a work of primary importance� in completing the �history of civilization which is the logical beginning point of Hobbes's thought�, and that a complete understanding of his political theory is impossible without his analysis of the way in which �doctrinal politics and disputative science� had created political chaos in England. This interpretation correctly emphasizes the role of ideas, as opposed to economic interests, in his explanation of civil conflict. It also rightly notes didactic continuities between Behemoth and his earlier work. However, I argue below that it overestimates the extent to which Hobbes treats the general idea of opinion as an eliminable product of �artificial� historical relations rather than as a permanent feature of human psychology and action. Thus, it discounts the extent to which his understanding of the relationship between opinion and civil war was a product of his philosophy rather than of a 'history of civilization'. (shrink)