Biology subjects

Kronbichler, L.

Publications and source records attributed to Kronbichler, L..

3 recordsLinked to original sources

bioRxiv2026

Dimensional and Categorical Predictors of Theory of Mind Network Activation: A transdiagnostic fMRI Study in Psychiatric Inpatients

Socio-cognitive alterations are widely observed across different psychiatric conditions, yet it remains unclear whether these deficits map onto distinct diagnostic categories or represent a shared transdiagnostic phenotype, driven by dimensional psychopathological symptom severity.This study evaluates Theory of Mind (ToM) network activation during a naturalistic functional magnetic resonance imaging (fMRI) movie paradigm in 313 participants, including 91 healthy controls and 222 psychiatric inpatients across five distinct diagnostic clusters (substance use, schizophrenia spectrum, affective, anxiety, and personality disorders). Frequentist analyses revealed decreased ToM-selective activity in psychiatric patients, compared to controls across all ToM regions of interest (ROIs). No significant difference emerged between diagnostic groups, but ROI activation correlated negatively with Adult Self-Report (ASR) scales (Total Problems, Internalising, Externalising). Subsequent Bayesian analysis of covariance (ANCOVAs) consistently favoured models that excluded traditional categorical diagnoses, suggesting that dimensional measures, especially Total Problems and Internalising, provided substantially greater predictive utility for ToM-related regional brain activation. Our findings challenge traditional categorical classifications in neurobiological research as they suggest that atypical mentalising might reflect a shared transdiagnostic vulnerability.

neuroscience↗

bioRxiv2022

Evaluating the capabilities and challenges of layer-fMRI VASO at 3T

Sub-millimeter functional imaging has the potential to capture cortical layer-specific functional information flow within and across brain systems. Recent sequence advancements of fMRI signal readout and contrast generations resulted in wide adaptation of layer-fMRI protocols across the global ultra-high-field (UHF) neuroimaging community. However, most layer-fMRI applications are confined to one of {approx}100 privileged UHF imaging centers, and sequence contrasts with unwanted sensitivity to large draining veins. In this work, we propose the application of vein-signal free vascular space occupancy (VASO) layerfMRI sequences at widely accessible 3T scanners. Specifically, we implement, characterize, and apply a cerebral blood volume (CBV)-sensitive VASO fMRI at a 3T scanner setup, as it is typically used in the majority of cognitive neuroscience and clinical neuroscience fMRI studies. We find that the longer [Formula], and stronger relative T1 contrast at 3T can account for some of the lower z-magnetization in the inversion-recovery VASO sequence compared to 7T and 9.4T. In the main series of experiments (N=16), we test the utility of this setup for motor tasks and find that-while being limited by thermal noise-3T layer-fMRI VASO is feasible within conventional scan durations. In a series of auxiliary studies, we furthermore explore the generalizability of the developed layer-fMRI protocols for a larger range of study designs including: visual stimulation, whole brain movie watching paradigms, and cognitive tasks with weaker effect sizes. We hope that the developed imaging protocols will help to increase accessibility of vein-signal free layer-fMRI imaging tools to a wider community of neuroimaging centers. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=179 SRC="FIGDIR/small/501554v1_ufig1.gif" ALT="Figure 1"> View larger version (66K): org.highwire.dtl.DTLVardef@1b2c6b5org.highwire.dtl.DTLVardef@139b13org.highwire.dtl.DTLVardef@129ff82org.highwire.dtl.DTLVardef@45e9d8_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

bioRxiv2022

Intrinsic Neural Timescales in Autism Spectrum Disorder and Schizophrenia. A Replication and Direct Comparison Study

Intrinsic neural timescales (INT) reflect the duration for which brain areas store information. A posterior - anterior hierarchy of increasingly longer INT has been revealed in both typically developed individuals (TD), as well as patients diagnosed with autism spectrum disorder (ASD) and schizophrenia (SZ), though INT are, overall, shorter in both patient groups. In the present study, we attempted to replicate previously reported group differences by comparing INT of TD to ASD and SZ. We replicated the previously reported result showing reduced INT in the left lateral occipital gyrus and the right post-central gyrus in SZ compared to TD. For the first time, we also directly compared the INT of the two patient groups and found that these same two areas show significantly reduced INT in SZ compared to ASD. In ASD, significant correlations were found between INT and their clinical and phenotypic characteristics. Our results point to the left lateral occipital gyrus and the right post-central gyrus as holding potential for further diagnostic refinement of SZ.

neuroscience↗