Electrophysiological Imaging Evaluation of Schizophrenia and Treatment Response

Abstract

Neuroimaging data provide various insights into altered functions and structures in the brain of subjects with schizophrenia. While some blood flow measures, e.g. functional magnetic resonance imaging and positron emission tomography, are characterized by high spatial resolutions, their time resolutions are in the range of second order. In contrast, electromagnetic recordings, e.g. electroencephalography (EEG) and magnetoencephalography, directly detect neural activity that occurs in the range of milli-second order. In spite of its feasibility, analysis with traditional EEG methods has been associated with the limited ability to localize aberrant signals. However, the recent development of imaging technique, such as low resolution electromagnetic tomography (LORETA) and its modified versions (e.g. sLORETA), improves the spatial resolution of EEG at rest and event-related potentials (ERPs), such as P300 and mismatch negativity by providing three-dimensional distribution pattern of these electrophysiological activities. In this chapter, the authors present recent findings from electrical neuroimaging studies of schizophrenia in relation to the neural basis of psychotic symptoms and cognitive deficits of the illness, as well as treatment response. These research areas are likely to facilitate the development of practical and reliable biomarkers to predict symptom severity, improve long-term outcome, and pave a new avenue to early intervention of schizophrenia.