| The aim of the project is to evaluate the neural substrate of meaning selection in healthy subjects and patients with schizophrenia, using functional magnetic resonance imaging (fMRI) and behavioral methods. The study will focus on homograph and idiom comprehension in sentence context. Test materials will be sentences containing either a homograph or an idiom. The homographs will be disambiguated either to the dominant or to the subordinate meaning in the sentence; while idioms will be biased toward their literal or idiomatic meaning. Non-ambiguous sentences will serve as controls. The primary method of the project will be functional fMRI in order to identify the neural activation patterns during the carrying out of the homograph and idiom comprehension tasks. Behavioral methods will complement the fMRI sessions. fMRI data will be analyzed by the SPM-99 statistical package. The lateral distribution of the activation pattern (Laterality Index) will be calculated on both the group and on the individual levels. The brain activation patterns will be compared to the behavioral data (idiom and homograph comprehension tasks). The main hypothesis of the project can be summarized as the following: The right hemisphere (RH) plays a role in meaning selection, therefore RH activation is expected to be found using fMRI in healthy subjects. Patients with schizophrenia are expected to show deviant neural activity during the meaning selection tasks. |
