INTRODUCTION: Contextual processing is often strongly deteriorated in schizophrenic patients as found, for example, in higher cognitive as well as lower visual paradigms. In visual detection tasks, impoverished contextual facilitation was attributed to aberrant excitatory neural circuits. On the other hand, we found contextual suppression, possibly related to neural inhibition, to be fast and intact in a visual backward masking task. Here, we combine a suppressive with a "protective" paradigm to further our understanding of the contextual deficiencies of schizophrenic patients in visual information processing. METHODS: Twenty three schizophrenic patients and 18 healthy controls were asked to discriminate the offset direction of a vernier target, which was followed by one of a variety of masks for several stimulus onset asynchronies (SOAs). RESULTS: As in previous studies, patients needed clearly longer SOAs than controls. However, when longer SOAs were taken into account, increases as well as decreases in backward mask strength had comparable effects in patients and controls. CONCLUSIONS: From these results, we suggest that complex spatial processing is fast and intact in schizophrenic patients.
INTRODUCTION: Contextual processing is often strongly deteriorated in schizophrenicpatients as found, for example, in higher cognitive as well as lower visual paradigms. In visual detection tasks, impoverished contextual facilitation was attributed to aberrant excitatory neural circuits. On the other hand, we found contextual suppression, possibly related to neural inhibition, to be fast and intact in a visual backward masking task. Here, we combine a suppressive with a "protective" paradigm to further our understanding of the contextual deficiencies of schizophrenicpatients in visual information processing. METHODS: Twenty three schizophrenicpatients and 18 healthy controls were asked to discriminate the offset direction of a vernier target, which was followed by one of a variety of masks for several stimulus onset asynchronies (SOAs). RESULTS: As in previous studies, patients needed clearly longer SOAs than controls. However, when longer SOAs were taken into account, increases as well as decreases in backward mask strength had comparable effects in patients and controls. CONCLUSIONS: From these results, we suggest that complex spatial processing is fast and intact in schizophrenicpatients.
Authors: Eka Chkonia; Maya Roinishvili; Natia Makhatadze; Lidia Tsverava; Andrea Stroux; Konrad Neumann; Michael H Herzog; Andreas Brand Journal: PLoS One Date: 2010-12-09 Impact factor: 3.240
Authors: George Bakanidze; Maya Roinishvili; Eka Chkonia; Werner Kitzrow; Sarina Richter; Konrad Neumann; Michael H Herzog; Andreas Brand; Imke Puls Journal: Front Psychiatry Date: 2013-10-22 Impact factor: 4.157