Search

Abstract: Although delusions are quite common symptoms among psychiatric patients, few neuroimaging studies have explored the neural correlates of delusions. In this study we used magnetoencephalography (MEG) to directly image brain activity associated with delusions in acute psychosis of epilepsy patients. Two female patients aged 65 and 68 years with temporal lobe epilepsy were studied. We obtained topographic images of the excess kurtosis (g2), the statistical index of spiky activities, from unaveraged MEG measurements using an analysis called “synthetic aperture magnetometry” (SAM). In both patients, the excess kurtosis (g2) images showed spiky activity over the right inferior parietal cortex during the delusional state. A second MEG measurement after delusions were resolved with antipsychotic medication showed no excess kurtosis image in the right parietal cortex. Our results indicate association of the right inferior parietal region with the experience of delusions in these patients. We suggest that MEG with SAM analysis is useful in the identification of abnormal activity in acute psychotic disorders. [Copyright &y& Elsevier]

Abstract: Magnetoencephalography (MEG) was used to image brain activity associated with delusions in episodic interictal psychosis of epilepsy. Two female patients aged 65 and 68 with temporal lobe epilepsy were studied during and after a delusional state. Topographic images of the excess kurtosis (g2), the statistical index of spikelike activity, were obtained from unaveraged MEG recordings using an analysis called “synthetic aperture magnetometry” (SAM). For both patients, MEG waveforms and excess kurtosis images revealed spiky activity in the right inferior parietal region during the delusional state. A second MEG measurement after delusions were resolved with antipsychotic therapy revealed no excess kurtosis in the right parietal area. Likewise, the sharp waves on MEG recordings disappeared as well. Our results suggest association of the right inferior parietal cortex, including the supramarginal gyrus, with the delusional state of episodic interictal psychosis of epilepsy. [Copyright &y& Elsevier]