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- Tønnesen, Siren, et al.
(författare)
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Brain Age Prediction Reveals Aberrant Brain White Matter in Schizophrenia and Bipolar Disorder : A Multisample Diffusion Tensor Imaging Study
- 2020
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Ingår i: Biological Psychiatry. - : Elsevier BV. - 2451-9022 .- 2451-9030. ; 5:12, s. 1095-1103
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Schizophrenia (SZ) and bipolar disorder (BD) share substantial neurodevelopmental components affecting brain maturation and architecture. This necessitates a dynamic lifespan perspective in which brain aberrations are inferred from deviations from expected lifespan trajectories. We applied machine learning to diffusion tensor imaging (DTI) indices of white matter structure and organization to estimate and compare brain age between patients with SZ, patients with BD, and healthy control (HC) subjects across 10 cohorts.METHODS: We trained 6 cross-validated models using different combinations of DTI data from 927 HC subjects (18-94 years of age) and applied the models to the test sets including 648 patients with SZ (18-66 years of age), 185 patients with BD (18-64 years of age), and 990 HC subjects (17-68 years of age), estimating the brain age for each participant. Group differences were assessed using linear models, accounting for age, sex, and scanner. A meta-analytic framework was applied to assess the heterogeneity and generalizability of the results.RESULTS: Tenfold cross-validation revealed high accuracy for all models. Compared with HC subjects, the model including all feature sets significantly overestimated the age of patients with SZ (Cohen's d = -0.29) and patients with BD (Cohen's d = 0.18), with similar effects for the other models. The meta-analysis converged on the same findings. Fractional anisotropy-based models showed larger group differences than the models based on other DTI-derived metrics.CONCLUSIONS: Brain age prediction based on DTI provides informative and robust proxies for brain white matter integrity. Our results further suggest that white matter aberrations in SZ and BD primarily consist of anatomically distributed deviations from expected lifespan trajectories that generalize across cohorts and scanners.
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| 2. |
- Visser, Renee M., et al.
(författare)
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A Naturalistic Paradigm to Investigate Postencoding Neural Activation Patterns in Relation to Subsequent Voluntary and Intrusive Recall of Distressing Events
- 2022
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Ingår i: Biological Psychiatry. - : Elsevier. - 2451-9022 .- 2451-9030. ; 7:10, s. 960-969
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: While neuroimaging has provided insights into the formation of episodic memories in relation to voluntary memory recall, less is known about neural mechanisms that cause memories to occur involuntarily, for example, as intrusive memories of trauma. Here, we investigated brain activity shortly after viewing distressing events as a function of whether memories for those events later intruded involuntarily. The postencoding period is particularly important because it is a period when clinical interventions could be applied. METHODS: A total of 32 healthy volunteers underwent functional magnetic resonance imaging while viewing distressing film clips, interspersed with 5 minutes of awake (postencoding) rest. Voluntary memories of the films were assessed using free recall and verbal and visual recognition tests after a week, while intrusive (involuntary) memories were recorded in a diary throughout that week. RESULTS: When analyzing functional magnetic resonance imaging responses related to watching the films, we replicated findings that those "hotspots " (salient moments within the films) that would later become intrusive memories elicited higher activation in parts of the brain's salience network. Surprisingly, while the postencoding persistence of multivoxel correlation structures associated with entire film clips predicted subsequent voluntary recall, there was no evidence that they predicted subsequent intrusions. CONCLUSIONS: Results replicate findings regarding the formation of intrusive memories during encoding and extend findings regarding the consolidation of information in postencoding rest in relation to voluntary memory. While we provided a first step using a naturalistic paradigm, further research is needed to elucidate the role of postencoding neural processes in the development of intrusive memories.
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| 3. |
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| 4. |
- Lindner, Philip, et al.
(författare)
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Associations of Psychopathic Traits With Local and Global Brain Network Topology in Young Adult Women
- 2018
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Ingår i: Biological Psychiatry. - : Elsevier BV. - 2451-9022 .- 2451-9030. ; 3:12, s. 1003-1012
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Tidskriftsartikel (refereegranskat)abstract
- Background: Psychopathic traits vary dimensionally in the population and are associated with multiple negative outcomes. The impaired integration theory (IIT) proposes that psychopathic traits are associated with abnormal neural network topology, such that disturbed integration of neural networks results in a self-perpetuating impairment in rapid integration and learning from multiple components of information. The IIT is based on findings from male offenders presenting high scores on all psychopathic traits. The present study investigated whether IIT predictions of topology abnormalities were associated with psychopathic traits, measured dimensionally, in young adult women with subsyndromal scores.Methods: Seventy-three women, with an average age of 25 years, were assessed using the Psychopathy Checklist–Revised and completed resting-state magnetic resonance imaging. Preprocessed time series from 90 anatomical regions were extracted to form connectivity matrices and used to calculate network topology based on graph theory. Correlations between total psychopathy and factor scores with both the raw connectivity matrix and global and local graph theory measures were computed.Results: Total psychopathy scores and behavioral factor scores were related to connectivity between several pairs of regions, primarily limbic/paralimbic. Psychopathic traits were not associated with global topology measures. Topology abnormalities, robust across network formation thresholds, were found in nodes of the default mode network and in hubs connecting several resting-state networks.Conclusions: IIT predictions of abnormal topology of hubs and default mode network nodes with dimensionally measured psychopathic traits were confirmed in a sample of young women. Regional abnormalities, accompanied by preserved global topology, may underlie context-specific abnormal information processing and integration.
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