| In this research project we will study on emotional prosody discrimination which is impaired in patients with schizophrenia. We presume that this contributes to the debilitating social dysfunction characteristic of the disorder. Evidence is found that brain lateralization of left-hemisphere language functions is reduced in schizophrenia. We test the hypothesis whether not only typical left- hemisphere functions (e.g., semantic processing) are less lateralized in schizophrenia, but also right-hemisphere functions (emotional prosody discrimination). To this end, we use a brain mapping technique that allows for causal inference, Transcranial Magnetic Stimulation (TMS). In the TMS studies we will contrast performance on tasks of emotional semantics (what is said, conveying which emotion) and emotional prosody (how it is said, emotional tone of voice) in four TMS conditions involving stimulation of 1) the right fronto-parietal operculum; 2) the left fronto-parietal operculum; 3) the right superior parietal lobule; and 4) the left superior parietal lobule. In the task described by Vingerhoets (Vingerhoets, 2003), subjects are required to identify the emotion conveyed by prosody or semantics of a number of sentences. Of the 24 sentences in each task, 6 are happy, 6 are sad, 6 are angry and 6 are fearful. We will investigate this pattern in healthy subjects, in healthy relatives of schizophrenia patients, schizophrenia patients and in Klinefelter syndrome, which has a genetic etiology, and has been associated with abnormal cerebral lateralization. |
