Neuroimaging; Eloquent Cortex; Neurosurgery; Language; Brain Connectivity
Coito Ana, Genetti Melanie, Pittau Francesca, Iannotti Giannina, Thomschewski Aljoscha, Höller Yvonne, Trinka Eugen, Wiest Roland, Seeck Margitta, Michel Christoph, Plomp Gijs, Vulliemoz Serge (2016), Altered directed functional connectivity in temporal lobe epilepsy in the absence of interictal spikes: A high density EEG study, in
Epilepsia, 57(3), 402-411.
Genetti Melanie, Tyrand Remi, Grouiller Frederic, Lascano Agustina, Vulliemoz Serge, Spinelli Laurent, Seeck Margitta, Schaller Karl, Michel Christoph (2015), Comparison of high gamma electrocorticography and fMRI with electrocortical stimulation for localization of somatosensory and language cortex, in
Clinical Neurophysiology, 126(1), 121-130.
Coito Ana, Michel Christoph, Mierlo Peter, Vulliemoz Serge, Plomp Gijs, Directed Functional Brain Connectivity Based on EEG Source Imaging: Methodology and Application to Temporal Lobe Epilepsy, in
IEEE Trans Biomed Eng..
The present project refers to the continuation of a pluri-disciplinary collaboration between neurosurgeons, epileptologists, neurophysiologists, neuropsychologists, and neuroradiologists, and it aims at a better understanding of the spatial allocation of language function in humans. The project is based on a contemporary dynamic-network-concept for functional allocation in the brain, which postulates the existence of interdependent neural circuits throughout the cerebral white matter for cognitive functions such as language. According to this concept a particular region may hold multiple functions, or multiple regions may hold the same one, respectively. This is opposed to the traditional modular localizational concept, according to which particular functions are localized in rather fixed cortical regions. A cohort of patients suffering from pharmacoresistant epilepsy, as well as patients with intrinsic tumors of the brain, who will undergo resective surgery shall be studied prospectively: Non-invasive structural and functional imaging (3D morphological MRI, DTI, and fMRI) and electrical source imaging (ESI) based on 256-channel EEG shall be performed together with neuropsychological tests - prior to surgery, and postoperatively at determined intervals. Particular focus will be put on a new method to analyze the ESI data that will take full advantage of the high temporal resolution of the EEG: It is based on time-varying partial directed coherence (PDC). Rigorous validation in animal models have shown that this method allows to determine information flow in the network and to identify the most active drivers, i.e. the most important “hubs” of the network. This analysis method will be applied to data already recorded during the previous grant period. In addition, the future patients and a new set of healthy volunteers shall undergo additional language tasks. Due to more precise allocation and hierarchization of language function, this project should prepare the avenue towards safer resection of tumors or epileptogenic zones in the neighborhood of, or, within eloquent brain regions.