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Bae, H.-J.

Publications and source records attributed to Bae, H.-J..

3 recordsLinked to original sources

Bayesian stroke modeling details sex biases in the white matter substrates of aphasia

Ischemic cerebrovascular events often lead to aphasia. Previous work provided hints that such strokes may affect women and men in distinct ways. Women tend to suffer strokes with more disabling language impairment, even if the lesion size is comparable to men. In 1,401 patients, we isolated data-led representations of anatomical lesion patterns and hand-tailored a Bayesian analytical solution to carefully model the degree of sex divergence in predicting language outcomes [~]3 months after stroke. We located lesion-outcome effects in the left-dominant language network that highlight the ventral pathway as a core lesion focus across different tests of language performance. We provide newly detailed evidence for sex-specific brain-behavior associations in the domain-general networks associated with cortico-subcortical pathways, with unique contributions of the fornix in women and cingular fiber bundles in men. Our collective findings suggest diverging white matter substrates in how stroke causes language deficits in women and men. Clinically acknowledging such sex disparities has the potential to improve personalized treatment for stroke patients worldwide.

neuroscience↗

Strategic infarct locations for post-stroke depressive symptoms: a lesion- and disconnection-symptom mapping study

BackgroundDepression is the most common neuropsychiatric complication after stroke. Infarct location is associated with post-stroke depressive symptoms (PSDS), but it remains debated which brain structures are critically involved. We performed a large-scale lesion-symptom mapping study to identify infarct locations, and white matter disconnections, associated with PSDS. MethodsWe included 553 patients (age 69{+/-}11 years, 42% female) with acute ischemic stroke. PSDS were measured using the 30-item Geriatric Depression Scale (GDS-30). Multivariable support vector regression (SVR)-based analyses were performed both at the level of individual voxels (SVR-VLSM) and predefined regions of interest (SVR-ROI) to relate infarct location to PSDS. We externally validated our findings in an independent stroke cohort (N=459). Finally, disconnectome-based analyses were performed using SVR-VLSM, in which white matter fibers disconnected by the infarct were analyzed instead of the infarct itself. Results: Infarcts in the right amygdala, right hippocampus and right pallidum were consistently associated with PSDS (permutation-based p<0.05) in SVR-VLSM and SVR-ROI. External validation (N=459) confirmed the association between infarcts in the right amygdala and pallidum, but not the right hippocampus, and PSDS. Disconnectome-based analyses revealed that disconnections in the right parahippocampal white matter, right thalamus and pallidum, and right anterior thalamic radiation were significantly associated (permutation-based p<0.05) with PSDS. ConclusionsInfarcts in the right amygdala and pallidum, and disconnections of right limbic and frontal cortico-basal ganglia-thalamic circuits, are associated with PSDS. Our findings provide a comprehensive and integrative picture of strategic infarct locations for PSDS, and shed new light on pathophysiological mechanisms of depression after stroke.

neuroscience↗

Generative lesion pattern decomposition of cognitive impairment after stroke

Cognitive impairment is a frequent and disabling sequela of stroke. There is however incomplete understanding of how lesion topographies in the left and right cerebral hemisphere brain interact to cause distinct cognitive deficits. We integrated machine learning and Bayesian hierarchical modeling to enable hemisphere-aware analysis of 1080 subacute ischemic stroke patients with deep profiling [~]3 months after stroke. We show relevance of the left hemisphere in the prediction of language and memory assessments, while global cognitive impairments were equally well predicted by lesion topographies from both sides. Damage to the hippocampal and occipital regions on the left were particularly informative about lost naming and memory function. Global cognitive impairment was predominantly linked to lesioned tissue in supramarginal and angular gyrus, the postcentral gyrus as well as the lateral occipital and opercular cortices of the left hemisphere. Hence, our analysis strategy uncovered that lesion patterns with unique hemispheric distributions are characteristic of how cognitive capacity is lost due to ischemic brain tissue damage.

neuroscience↗