Kedves Kollégák! Ezúton szeretném meghívni Önöket az MTA TTK Agyi Képalkotó Központ szervezésében megrendezésre kerülő előadásra, amelyet Prof. Kovács Gyula tart *Intact repetition probability effects in Schizophrenia *címmel. Az előadás időpontja: 2015. május 19. (kedd) 14 óra Helyszín: MTA TTK, 1117 Budapest, Magyar tudósok körútja 2. Az előadás kivonata alább olvasható. Tisztelettel, Hermann Petra *Intact repetition probability effects in Schizophrenia* Gyula Kovács1,2,4, Mareike Grotheer1,2, Lisa Münke3, Szabolcs Kéri4, Igor Nenadic3 1 Institute of Psychology, Friedrich Schiller University Jena, 07743 Jena, Germany 2 DFG Research Unit Person Perception, Friedrich Schiller University Jena, 07743 Jena, Germany 3 Department of Psychiatry and Psychotherapy, Jena University Hospital, 07743 Jena, Germany 4 Department of Cognitive Science, Budapest University of Technology and Economics, 1111 Budapest, Hungary Abstract A growing body of evidences suggests that the comparison of expected and incoming sensory stimuli (the predictive error (ε) processing) is impaired in schizophrenia patients (SZ). For example in studies of mismatch negativity, an ERP component that signals ε, SZ patients show deficits in both the auditory and visual modalities. In order to test the role of impaired ε processing further in SZ, using neuroimaging methods, we applied a repetition suppression (RS) paradigm. Patients diagnosed with SZ (n=17) as well as age and gender matched healthy control subjects (HC, n=17) were presented with pairs of faces, which could either repeat or alternate. Additionally, the likelihood of repetition/alternation trials was modulated in individual blocks of fMRI recordings, testing the effects of repetition probability (P(rep)) on RS. We found a significant RS in the fusiform and occipital face areas, as well as in the lateral occipital cortex that was similar in both subject groups. More importantly, we observed similar P(rep) effects (larger RS in blocks with high frequency of repetitions than in blocks with low repetition likelihood) in both subject groups as well. Crucially, this suggests that repetition reduces the top-down ε for expected, compared to unexpected stimuli in patients with Schizophrenia as well.