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Fan, Y.-S.

Publications and source records attributed to Fan, Y.-S..

3 recordsLinked to original sources

Contracted anterior-posterior systematic covariance of cortical thickness in early-onset schizophrenia

Background and HypothesisSchizophrenia is a neurodevelopmental condition with alterations in both sensory and association cortical areas. These alterations have been reported to follow structural connectivity patterning, and to occur in a system-level fashion. Here, we investigated whether pathological alterations of schizophrenia originated from an early disruption of cortical organization by using 7-17-years-old individuals with early-onset schizophrenia (EOS). Study DesignWe estimated cortical thickness using T1-weighted structural MRI data from 95 patients with antipsychotic-naive first-episode EOS and 99 typically developing (TD) controls. We then computed structural covariance of cortical thickness and estimated system-level organizational axes by performing nonlinear dimensionality reduction techniques on covariance matrices for the EOS and TD groups. Finally, we tested for group differences between EOS and TD individuals in terms of both structural covariance and covariance distances along the systematic axis. Study ResultsThe first covariance gradient differentiated motor regions from other cortical areas. Similar to the macrostructural axis in adults, the second gradient axis in young TD discriminated anterior from posterior regions and was compressed in EOS patients relative to TD controls. In addition, patients showed increased structural covariance between two ends of the systematic axis, with increased geodesic distance of covarying regions between two ends. ConclusionOur findings revealed a contracted organizational axis of cortical thickness in EOS patients, which was attributed to excessive distally coordinated changes between anterior and posterior regions of the cortex. Taken together, our study suggests a possible early disruption of system-level neurodevelopment in schizophrenia.

pathology↗

Neurodevelopmentally rooted epicenters in schizophrenia: sensorimotor-association spatial axis of cortical thickness alterations

Pathologic perturbations in schizophrenia have been suggested to propagate via the functional and structural connectome across the lifespan. Yet how the connectome guides early cortical reorganization of developing schizophrenia remains unknown. Here, we used early-onset schizophrenia (EOS) as a neurodevelopmental disease model to investigate putative early pathologic origins that propagate through the functional and structural connectome. We compared 95 patients with antipsychotic-naive first-episode EOS and 99 typically developing controls (7-17 years of age, 120 females). Whereas patients showed widespread cortical thickness reductions, thickness increases were observed in primary cortical areas. Using normative connectomics models, we found that epicenters of thickness reductions were situated in association regions linked to language, affective, and cognitive functions, while epicenters of increased thickness in EOS were located in sensorimotor regions subserving visual, somatosensory, and motor functions. Using post-mortem transcriptomic data of six donors, we observed that the epicenter map differentiated oligodendrocyte-related transcriptional changes at its sensory apex and the association end was related to expression of excitatory/inhibitory neurons. More generally, we observed that the epicenter map was associated with neurodevelopmental disease gene dysregulation and human accelerated region genes, suggesting potential shared genetic determinants across various neurodevelopmental disorders. Taken together, our results underscore the developmentally rooted pathologic origins of schizophrenia and their transcriptomic overlap with other neurodevelopmental diseases.

neuroscience↗

Macroscale Thalamic Functional Organization Disturbances And Underlying Core Cytoarchitecture In Early-Onset Schizophrenia

Schizophrenia is a polygenetic mental disorder with heterogeneous positive and negative symptom constellations, and is associated with abnormal cortical connectivity. The thalamus has a coordinative role in cortical function and is key to the development of the cerebral cortex. Conversely, altered functional organization of the thalamus might relate to overarching cortical disruptions in schizophrenia, anchored in development. Here, we contrasted resting-state fMRI in 99 antipsychotic-naive first-episode early-onset schizophrenia (EOS) patients and 100 typically developing controls to study whether macroscale thalamic organization is altered in EOS. Employing dimensional reduction techniques on thalamocortical functional connectome, we derived lateral-medial and anterior-posterior thalamic functional axes. We observed increased segregation of macroscale thalamic functional organization in EOS patients, which was related to altered thalamocortical interactions both in unimodal and transmodal networks. Using an ex vivo approximation of core-matrix cell distribution, we found that core cells particularly underlie the macroscale abnormalities in EOS patients. Moreover, the disruptions were associated with schizophrenia-related gene expression maps. Behavioral and disorder decoding analyses indicated that the macroscale hierarchy disturbances might perturb both perceptual and abstract cognitive functions and contribute to negative syndromes in schizophrenia, suggesting a unitary pathophysiological framework of schizophrenia.

neuroscience↗