Disruptions of Hierarchical Cortical Organisation in Early Psychosis and Schizophrenia

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: May 2, 2023

Abstract Background The cerebral cortex is organised hierarchically along an axis that spans unimodal sensorimotor to transmodal association areas. This hierarchy often characterised using low-dimensional embeddings, termed gradients, of inter-regional functional coupling estimates measured with resting-state magnetic resonance imaging (fMRI). Such analyses may offer insights into the pathophysiology schizophrenia, which frequently linked dysfunctional interactions between and Methods To examine disruptions hierarchical cortical function across distinct stages psychosis, we applied diffusion map embedding two independent fMRI datasets: one comprised 114 patients early psychosis 48 controls, other comprising 50 established schizophrenia 121 controls. We then analysed primary sensory-fugal secondary visual-to-sensorimotor gradients each participant in both datasets. Results There were no significant differences regional gradient scores Patients showed secondary, but not primary, relative Gradient by lower within-network dispersion Dorsal Attention (p FDR <.001), Visual (pFDR=.003), Frontoparietal (pFDR=.018), Limbic (pFDR=.020) networks between-network network (pFDR<.001). Conclusions These findings indicate occur rather than axis, as previously thought. absence suggests visual-sensorimotor abnormalities emerge illness progresses.

Language: Английский

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Spatial profiles provide sensitive MRI measures of the midbrain micro- and macrostructure

NeuroImage, Journal Year: 2022, Volume and Issue: 264, P. 119660 - 119660

Published: Oct. 8, 2022

The midbrain is the rostral-most part of brainstem. It contains numerous nuclei and white matter tracts, which are involved in motor, auditory visual processing, changes their structure function have been associated with aging, as well neurodegenerative disorders. Current tools for estimating subregions MRI require high resolution multi-parametric quantitative measures. We propose an approach that relies on morphology to calculate profiles along show these sensitive underlying macrostructure midbrain. First, we can be sampled, within subject space, three main axes left right midbrain, producing similar across subjects. use two data sets different field strengths, contain R1, R2* QSM maps highly correlated both subjects between datasets. Next, compare sample ROIs, first a way reliably separates structures, i.e., substantia nigra, red nucleus, periaqueductal gray. further age differences localized specific nuclei, reflected profiles. Finally, generalize same third clinically relevant dataset using HCP subjects, metrics such diffusion tensor semi-quantitative T1w/T2w maps. Our results suggest profiles, estimates calculated native rely simple measurements. it robust easily expanded datasets, hope will great community study particular.

Language: Английский

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Multiparametric quantitative MRI uncovers putamen microstructural changes in Parkinson's Disease

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: May 31, 2024

Abstract Parkinson’s disease (PD) is a progressive neurodegenerative disorder dominated by motor and non-motor dysfunction. Despite extensive research, the in vivo characterization of PD-related microstructural brain changes remains an ongoing challenge, limiting advancements diagnostic therapeutic strategies. The putamen, critical structure within basal ganglia, plays key role regulating movement profoundly affected early neurodegeneration. In this study, we collected multiparametric quantitative MRI (qMRI) data PD patients healthy controls, to investigate alterations putamen PD. We utilized gradient analysis technique analyze spatial variations various qMRI parameters, including relaxation rates (R1, R2, R2*), water fraction (WF), susceptibility, magnetization transfer saturation (MTsat), diffusion metrics (MD, FA). Our findings reveal significant gradients interhemispheric asymmetries these biophysical properties along anterior-posterior axis putamen. Notably, exhibited increased altered transverse rate R2*, particularly posterior correlated with symptom laterality. These suggest underlying tissue atrophy or neuroinflammatory processes associated study underscores importance as focal point for pathology highlights potential localized detecting subtle yet clinically changes. new dataset provides valuable insights into pathology, potentially aiding development more precise tools targeted therapies.

Language: Английский

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Normative trajectories of R1, R2* and magnetic susceptibility in basal ganglia on healthy ageing

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: July 22, 2024

Abstract Quantitative MRI techniques, including R 1 , 2 *, and magnetic susceptibility mapping, have emerged as promising tools for generating surrogate imaging markers of brain tissue microstructure, enabling non-invasive in vivo measurements associated with myelination iron deposition. Gaining insights into how these quantitative evolve throughout a normal lifespan can enhance our understanding maturation processes facilitate the study disease-related microstructural changes by distinguishing pathological alterations from development. In this study, we established normative trajectories basal ganglia at 3T. We used healthy ageing cohort comprising 260 subjects an evenly distributed age range sex ratio adulthood. Utilizing non-parametric Gaussian Process Regression model to derive trajectories, found that structures predominantly exhibit quadratic shape over age, while * are primarily linear. validated using independent cohort. Additionally, demonstrated spatial distributions parameters also change putamen caudate nucleus. This not only reinforces existing findings on association between qMRI but provides valuable resources studying cognitive ageing, conjunction behavioural data available same collection.

Language: Английский

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Transcriptomic profiles link corticostriatal microarchitecture to genetics of neurodevelopment and neuropsychiatric risks

Research Square (Research Square), Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 26, 2024

Many studies on macroscale organization have focused only the cerebral cortex or striatum, leaving a large gap in hierarchy of corticostriatal microstructural covariance. Here, we partitioned striatum into seven distinct parcels and computed covariance between each parcel using T1-weighted/T2-weighted mapping. We found that exhibited hierarchical gradient along anterior-posterior axis striatum. The patterns are linked to geodesic distance cell type-specific gene expression profiles, revealing gradually attenuated relationship Linking profile showed transcriptional variations genes different anterior posterior suggested more enriched psychiatric disorders. Moreover, at genetic level, microarchitecture spatiotemporal trait during neurodevelopment. Finally, identified neural circuits from limbic medial frontal contributes common neuropsychiatric Collectively, our findings reveal spatially covarying specializations architectures covariance, highlighting mechanisms underlying neurodevelopmental may be involved

Language: Английский

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