ABSTRACT
BACKGROUND AND PURPOSE: The main challenge in assessing patients with epilepsy is the localization of neuronal networks involved in seizure generation and the lateralization of seizure onset. Electro encephalogram-functional magnetic resonance imaging (EEG-fMRI) is a noninvasive multimodal imaging technique for epilepsies where the data is acquired based on the interictal epileptiform discharges (IED). Since this is a new technique, the specificity for lateralizing epileptic focus is yet to be established. The peak blood oxygen level dependent (BOLD) signal in an interictal recording is known to correlate with seizure onset focus. In this study we are proposing a simple and practical method without the need for high end post processing techniques of fmri data. The peak BOLD signal derived from EEG-fMRI aids to lateralise seizure focus in a given cerebral lobe (region of interest, ROI). This is a very useful tool in a clinical setting on a given individual clinical case, when other modalities may be conflicting or inconclusive. METHODS: We analyzed simultaneous EEG-fMRI of 10 different types of refractory epilepsy. The lateralization index was calculated from the statistical significant clusters obtained between the different ROI and results were validated with other modalities. RESULTS: Lateralization of seizure focus corroborated well in temporal and extratemporal lobe epilepsy, reflex epilepsy and lesional epilepsy. The only drawback of EEG-fMRI in our study was if insignificant BOLD changes were associated with the given IED. CONCLUSIONS: EEG-fMRI can be helpful additional tool in the pre-surgical work-up of refractory epilepsy particularly when lateralization with other modalities is conflicting or inconclusive.
ABSTRACT
BACKGROUND: Emotion entails cognitive processes that may either be conscious or unconscious. Emotions influence all aspects of cognition. AIM: The aim of the following study was to study the effect of education on neural correlates of emotions in healthy normal volunteers. MATERIALS AND METHODS: Sample consisted total of 61 healthy young educated adults in the age range of 18-40 years. The volunteers were asked to view neutral, pleasant and unpleasant pictures from international affective picture system in a magnetic resonance imaging (MRI) scanner. STATISTICS ANALYSIS: Rest-active block design paradigm, functional MRI results analyzed in statistical parametric mapping 8. RESULTS AND CONCLUSION: Activations associated with emotions were present in cerebral and cerebellar regions. Education influences emotion.
