Executive functions are high-level cognitive processes involving abilities such as working memory/updating, set-shifting and inhibition. These complex cognitive functions are enabled by interactions among widely distributed cognitive networks, supported by white matter tracts. Executive impairment is frequent in neurological conditions affecting white matter; however, whether specific tracts are crucial for normal executive functions is unclear.
View Article and Find Full Text PDFObjective: To infer the face-based mentalizing network from resting-state functional MRI (rsfMRI) using a seed-based correlation analysis with regions of interest identified during intraoperative cortical electrostimulation.
Methods: We retrospectively included 23 patients in whom cortical electrostimulation induced transient face-based mentalizing impairment during 'awake' craniotomy for resection of a right-sided diffuse low-grade glioma. Positive stimulation sites were recorded and transferred to the patients' preoperative normalized MRI, and then used as seeds for subsequent seed-to-voxel functional connectivity analyses.
Recent evidence from axonal stimulation mapping studies suggests that at least two white matter connectivities in the right hemisphere may be involved in face-based mentalizing, i.e. the ability to infer complex cognitive and affective states from human faces: the inferior fronto-occipital (IFOF) and the superior longitudinal/arcuate (SLF/AF) fasciculi.
View Article and Find Full Text PDFLeft spatial neglect is a debilitating condition that may occur after lesion of many cortical territories in the right hemisphere. At the subcortical level, the second and third branches of the right superior longitudinal fasciculus has emerged as strong candidates in conveying information exchanges within the attention networks as their damage has been repeatedly associated to spatial neglect in neuromodulation and neuropsychological studies. Yet, a few cases of spatial neglect have also been observed after damage to the right inferior fronto-occipital fasciculus (IFOF), suggesting an involvement of this associative connectivity in spatial attention.
View Article and Find Full Text PDFOver the past few years, considerable progress has been done in clarifying the neural networks underlying mentalizing. However, although the cortical architecture of this function is relatively well understood, the white matter pathways that may be involved in conveying neural signals within the mentalizing network remain to be elucidated. To gain insight into this matter, a detailed stimulation mapping of face-based mentalizing was performed in 27 patients undergoing awake surgery for a right-sided diffuse low-grade glioma (DLGG).
View Article and Find Full Text PDFObject: Multicentric diffuse low-grade gliomas (DLGGs) are defined as widely separated lesions in different lobes or hemispheres where there is no anatomical continuity between lesions. This condition is rare and its clinicopathological characteristics have been scarcely described in the literature. Here, the authors report the first consecutive surgical series of multicentric DLGGs with functional and oncological outcomes.
View Article and Find Full Text PDFObject: It has been demonstrated that an extensive resection (total or subtotal) may significantly increase the overall survival in patients with WHO Grade II gliomas (low-grade gliomas [LGGs]). Yet, recent data have shown that conventional MR imaging underestimates the spatial extent of LGG, since tumor cells were found up to 20 mm around MR imaging abnormalities. Thus, it was hypothesized that an extended resection with a margin beyond MR imaging-defined abnormalities-a "supratotal" resection-might improve the outcome of LGG.
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