Evaluation therapeutischer Effekte mittels fMRT bei ersterkrankten schizophrenen Patienten

Zusammenfassung

Im Rahmen des Teilprojektes “Hirnfunktionale Indikatoren des Rezidivrisikos” des Kompetenznetzes Schizophrenie konnten in einer multizentrischen fMRT-Untersuchung Minderaktivierungen ersterkrankter schizophrener Patienten während Arbeitsgedächtnisprozessen beschrieben werden. Hier waren insbesondere Hypoaktivierungen parietaler Areale sowie Hyperaktivierungen in inferior frontalen Hirnbereichen nachweisbar. Bei den Patienten war eine positive Korrelation zwischen der Güte der Leistung im verwendeten Paradigma und der Aktivierung des dorsolateralen Präfrontalkortex zu beobachten, einer Region, die immer wieder im Zentrum der bildgebenden Forschung zur Pathophysiologie der Schizophrenie steht und eng mit Arbeitsgedächtnisprozessen assoziiert ist. Wiederholungsmessungen weisen auf zerebrale Reorganisationsprozesse und eine Annäherung des Aktivierungsmusters der Patienten an das der Gesunden als Folge der mehrmonatigen Therapie hin. Weiterführende Analysen werden sich auf eine Prädiktion für den individuellen Erkrankungsverlauf fokussieren.

Summary

Within the multicenter fmri project “Cerebral indicators of relapse”, which is part of the German Competence Network on Schizophrenia, circumscribed hypoactivations in firstepisode schizophrenia patients during working memory demands emerged. These hypoactivations were predominately striking in parietal areas, while inferior frontal brain regions were hyperactivated compared to healthy controls. In patients, a positive correlation between performance quality and dorsolateral prefrontal activity could be observed,a region frequently focused at in imaging studies on schizophrenia and which is closely associated with working memory processes. Reassessments of patients point to cerebral reorganisation processes in that functional differences between patients and controls become less pronounced. Extended analyses will focus on the individual predictive value of cerebral dysfunctions present already at the onset of schizophrenia.

Schlüsselwörter

Ersterkrankung - Schizophrenie - fMRT - Arbeitsgedächtnis

Keywords

First-episode schizophrenia - fmri - working memory

• Literatur

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