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Latreche, C.

Publications and source records attributed to Latreche, C..

2 recordsLinked to original sources

Claustrum Morphometry Reveals Spatially Heterogeneous Alterations in 22q11DS

The human claustrum is a small, irregular, and complexly positioned structure, yet it carries long range projections to most cortical regions responsible for executive functioning. Prior structural MRI research has largely relied on global volume as the metric of its morphology. Such measures may obscure regionally specific morphological changes relevant to developmental and pathological variation. We therefore addressed this limitation by applying longitudinal surface-based morphometry to 874 scans from 440 individuals aged 5-35 years, comparing typical development with 22q11.2 deletion syndrome (22q11DS), a genetic condition characterized by brain dysmaturation, and assessing associations with working memory performance. Our data show a significant age-related volumetric decline that is reduced in 22q11DS left claustra, while surface deformation and thickness analyses revealed spatial patterns unique to hemisphere, group, and developmental age. In controls, the claustrum surface deformed with age in clustered zones along a dorsoventral gradient, and the dorsal-anterior zone thinned across development while the ventral zone thickened. 22q11DS claustra showed less age-related deformation than controls, whose claustrum surface changes associated with verbal working memory. This structural correlate was statistically equivalent to zero in carriers, consistent with a disrupted claustral development to the working memory vulnerability of the syndrome. These findings show the value of surface-based morphometry over volume alone, highlight dysmaturation and regionally organized claustrum shape variation, and suggest that disrupted structural organization is accompanied by a weaker claustrum-working memory association.

neuroscience↗

Neural integration and segregation revealed by a joint time-vertex connectome spectral analysis

Brain oscillations are produced by the coordinated activity of large groups of neurons and different rhythms are thought to reflect different modes of information processing. These modes, in turn, are known to occur at different spatial scales. Nevertheless, how these rhythms support different modes of information processing at the brain scale is not yet fully understood. Here we present "Joint Time-Vertex Connectome Spectral Analysis", a framework for characterizing the spectral content of brain activity both in time (temporal frequencies) and in space (spatial connectome harmonics). This method allows us to estimate the contribution of integration (global communication) and segregation (functional specialization) mechanisms at different temporal frequency bands in source-reconstructed M/EEG signals, thus providing a better understanding of the complex interplay between different information processing modes. We validated our method on two different datasets, an auditory steady-state response (ASSR) and a visual grating task. Our results suggest that different information processing mechanisms are carried out at different frequency channels: while integration seems to be a specific mechanism occurring at low temporal frequencies (alpha and theta), segregation is only observed at higher temporal frequencies (high and low gamma). Crucially, the estimated contribution of the integration and segregation mechanisms predicts performance in a behavioral task, demonstrating the neurophysiological relevance of this new framework.

neuroscience↗