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Prior studies have used functional neuroimaging to demonstrate that the organization of the autistic brain is different from that of the non-autistic brain. Similarly, patients with epilepsy have also shown cortical reorganization. We present a case study that provides direct confirmation of disorganized sensorimotor distribution in a patient with autism spectrum disorder and epilepsy. To our knowledge, this is the first time cortical mapping directly showing abnormal cortical organization in a patient with autism spectrum disorder and epilepsy has been reported in the literature.

In this work, electrocorticographic temporal alteration mapping (ETAM) was proposed for motor cortex mapping by utilizing movement-related cortical potentials (MRCPs) within [0.05 3] Hz low frequency band. This MRCP waveform-based temporal domain approach was compared with the state-of-the-art electrocorticographic frequency alteration mapping (EFAM), which was based on high frequency spectrum dynamics. Five patients (2 epilepsy cases and 3 tumor cases) were enrolled in this study. Each patient had intraoperative direct electrocortical stimulation (DECS) procedure for motor cortex localization, and the patient was required to perform simple brisk wrist extension task during awake craniotomy surgery. Cross-validation results shown that the proposed ETAM method had a high performance in sensitivity (81.82%) and specificity (94.33%) for identifying sites which exhibited positive DECS motor responses. No significant difference in sensitivity was observed between ETAM and EFAM methods. However, the proposed ETAM was much higher in specificity as compared with EFAM (94.33% vs. 86.08%). Our results indicated that for the intraoperative functional brain mapping, ETAM was a promising novel approach for motor cortex localization and had a great potential to reduce the needs for cortical electrical stimulation.

Magnetoencephalography (MEG) is a novel functional brain mapping technique capable of non-invasively measuring neurophysiological activity based on direct measures of the magnetic flux at the head surface associated with the synchronized electrical activity of neuronal populations. Among the most actively sought applications of MEG has been localization of language-specific cortex. This is in part due to its practical application for pre-surgical evaluation of patients with epilepsy or brain tumors. Until recently, comprehensive language mapping during surgical planning has relied on the application of invasive diagnostic methods, namely the Wada procedure and direct electrocortical stimulation mapping, often considered as the "gold standard" techniques for identifying language-specific cortex. In this review, we evaluate the utility of MEG as a tool for functional mapping of language in both clinical and normal populations. In particular, we provide a general description of MEG, with emphasis on facets of the technique related to language mapping. Additionally, we discuss the application of appropriate MEG language-mapping protocols developed to reliably generate spatiotemporal profiles of language activity, and address the validity of the technique against the "gold standards" of the Wada and electrocortical mapping procedures.

Mapping functional areas of the brain is important for planning tumour resections. With the increased use of functional magnetic resonance imaging (fMRI) for presurgical planning, there is a need to validate that fMRI activation mapping is consistent with the mapping obtained during surgery using direct electrocortical stimulation (DECS).A quantitative comparison of DECS and fMRI mapping techniques was performed, using a patient-specific conductivity model to find the current distribution resulting from each stimulation site. The resulting DECS stimulation map was compared to the fMRI activation map, using the maximal Dice similarity coefficient (MDSC).Our results show some agreement between these two mapping techniques--the stimulation site with the largest MOSC was the only site that demonstrated intra-operative effect.There is a substantial effort to improve the techniques used to map functional areas, particularly using fMRI. It seems likely that fMRI will eventually provide a valid non-invasive means for functional mapping.