Overview
The purpose of this study is to compare organization of normal brain function as detected using Functional magnetic resonance imaging (fMRI) in normal subjects as opposed to patients with epilepsy or brain tumors, to ascribe precise anatomic labels (including Brodmann Areas) and functional significance to each region involved in cognitive processes as detected by cortical stimulation mapping (CSM) in patients with implanted subdural electrodes (SDE) or depth (sEEG) electrodes, to describe the locations of these regions in Talairach space, for a population of patients without overt structural abnormalities in these regions, to generate a spatial probability map of locations of cortical regions "essential" for these processes, to compare the loci of "crucial" language, visual, motor and cognitive sites as determined by CSM with the loci determined by a battery of tasks using fMRI for each individual and to use these data in patients undergoing intracranial electro-corticographyto determine the loci of essential, involved and uninvolved brain areas, and use sophisticated mathematical analyses of these intracranial recordings to study information flow between these areas.
Eligibility
Inclusion Criteria:
- patients with medically refractory epilepsy who are scheduled to undergo or have previously undergone placement of sub-dural electrodes (including depth electrodes) to localize the site of seizure onset and to map the locations of critical language and motor regions
- patients with epilepsy, brain tumors or cortically based vascular malformations (cavernous malformations or arterio-venous malformations) with lesions that are/were proximate to crucial brain regions, and who are scheduled to undergo or have previously undergone intra-op mapping of motor, visual or language function, or a Wada test, or maybe part of an awake craniotomy.
- proficiency in English
Exclusion Criteria:
- Gross structural abnormalities (large hamartomata, tumors, large vascular malformations, very large diffuse malformations of cortical development) that may have impacted upon the location of critical brain areas.
- Unable to participate in testing due to impaired cognition or mental retardation.
- Cardiac pacemakers, intracranial aneurysm clips, or other potentially mobile implanted metallic devices
- Patients with claustrophobia who cannot undergo an MRI scan without sedation