Autor:innen:
Frederike Stein, Marburg (Germany)
Katharina Brosch, Marburg (Germany)
Kai Gustav Ringwald, Marburg (Germany)
Julia Pfarr, Marburg (Germany)
Susanne Meinert, Münster (Germany)
Alexandra Winter, Münster (Germany)
Udo Dannlowski, Münster (Germany)
Igor Nenadic, Marburg (Germany)
Axel Krug, Bonn (Germany)
Tilo T. J. Kircher, Marburg (Germany)
Objective:
Factorial dimensions and neurobiological underpinnings of formal thought disorders (FTD) have been extensively investigated in schizophrenia spectrum disorders (SSD). However, FTD are also highly prevalent in other disorders. Still, there is a lack of knowledge about transdiagnostic, structural brain correlates of FTD.
Method:
In N=1,071 patients suffering from DSM-IV major depressive disorder, bipolar disorder, or SSD, we calculated a psychopathological factor model of FTD based on the SAPS and SANS scales. We tested the association of FTD dimensions with 3 T MRI measured gray matter volume (GMV) and DTI white matter fractional anisotropy (FA) using regression and interaction models in SPM12. We performed post hoc confirmatory analyses in diagnostically equally distributed, age- and sex-matched sub-samples to test whether results were driven by diagnostic categories.
Results:
Cross-validation (explorative and confirmatory) factor analyses revealed three psychopathological FTD factors: verbosity, emptiness and disorganization. The verbosity dimension was negatively correlated with a GMV cluster comprising parts of the middle occipital and angular gyri and positively with FA in the right posterior cingulum bundle and inferior longitudinal fascicle. Emptiness was negatively associated with left hippocampus and thalamus GMV. Disorganization was negatively associated with FA in bilateral anterior thalamic radiation, and positively with the hippocampal part of the right cingulum bundle. None of the gray or white matter associations interacted with diagnosis.
Conclusion:
Our results provide a refined mapping of FTD phenotype dimensions and neuroanatomical signatures, pointing to language associated gray and white matter structures that are involved in FTD domains, independent of DSM-IV disorder.