Showing papers by "George Paxinos published in 2022"
TL;DR: A comprehensive dataset of two healthy male volunteers reconstructed to a 0.25 mm3 isotropic resolution for T1w, T2w and DWI contrasts serves as an illustration on what features contrasts and relations can be used to interpret MRI datasets, in research, clinical and education settings.
Abstract: We introduce HumanBrainAtlas, an initiative to construct a highly detailed, open-access atlas of the living human brain that combines high-resolution in vivo MR imaging and detailed segmentations previously possible only in histological preparations. Here, we present and evaluate the first step of this initiative: a comprehensive dataset of two healthy male volunteers reconstructed to a 0.25 mm3 isotropic resolution for T1w, T2w and DWI contrasts. Multiple high-resolution acquisitions were collected for each contrast and each participant, followed by averaging using symmetric group-wise normalisation (Advanced Normalisation Tools). The resulting image quality permits structural parcellations rivalling histology-based atlases, while maintaining the advantages of in vivo MRI. For example, components of the thalamus, hypothalamus, and hippocampus - difficult or often impossible to identify using standard MRI protocols, can be identified within the present data. Our data are virtually distortion free, fully 3D, and compatible with existing in vivo Neuroimaging analysis tools. The dataset is suitable for teaching and is publicly available via our website (www.hba.neura.edu.au), which also provides data processing scripts. Instead of focusing on coordinates in an averaged brain space, our approach focuses on providing an example segmentation at great detail in the high quality individual brain, this serves as an illustration on what features contrasts and relations can be used to interpret MRI datasets, in research, clinical and education settings.
2 citations
TL;DR: A new whole-brain map of the rhesus macaque based on the anatomical connectivity profile provided by high-resolution angular and spatial diffusion MRI data is created to provide a backbone of the mesoscopic connectivity and a multi-omics atlas to facilitate translational medicine, cross-species comparisons, and computational modelling, enriching the collaborative resource platform of nonhuman primate data.
Abstract: The rhesus macaque ( Macaca mulatta ) is a crucial experimental animal that shares many genetic, brain 44 organizational, and behavioral characteristics with humans. A macaque brain atlas that identifies anatomically 45 and functionally distinct regions is fundamental to biomedical and evolutionary research. However, even though connectivity information is vital for understanding brain functions, a connectivity-based whole-brain atlas of 47 the macaque has not previously been made. In this study, we created a new whole-brain map, the Macaque 48 Brainnetome Atlas, based on the anatomical connectivity profile provided by high-resolution angular and spatial 49 diffusion MRI data. The new atlas consists of 248 cortical and 56 subcortical regions as well as their structural and resting-state functional connections. We systematically evaluated the parcellations and connections using multi-site and multi-modal datasets to ensure reproducibility and reliability. The resulting resource, which is 52 downloadable from http://atlas.brainnetome.org, includes (1) the thoroughly delineated Macaque Brainnetome 53 Atlas (MacBNA), (2) the multi-modal connections, (3) the largest postmortem high resolution macaque dMRI 54 dataset, and (4) ex vivo MRI, block-face, and Nissl-stained images obtained from a different macaque. We 55 provide an exemplar use of the resource with a joint multi-modal and multi-scale utilization of MRI and Nissl 56 data with our atlas as a reference system. The goals of the resource are not only to provide a backbone of the 57 mesoscopic connectivity and a multi-omics (such as transcriptomes and proteomes) atlas but also to facilitate 58 translational medicine, cross-species comparisons, and computational modelling, enriching the collaborative 59 resource platform of nonhuman primate data. In the current study, we present a fine-grained anatomical connectivity-based brain atlas of macaques, the Macaque Brainnetome Atlas (MacBNA), using high spatial and angular resolution dMRI images of 8 postmortem monkeys acquired with an ultra-high field 9.4T MRI scanner. We replicated the Macaque Brainnetome Atlas parcellation using an independent open public ex vivo macaque brain dataset. The anatomical connections from the postmortem dMRI data were validated by comparisons with invasive tracer data, the gold standard for connections. We also present a set of Nissl-stained sections from another monkey The Macaque based on which various profiles of brain regions were characterized at different levels using multi-modal and multi-scale data integrated into a unifying map 10,43–45 . The MacBNA consists of 248 cortical and 56 subcortical subregions identified by anatomical connectivity obtained from acquired high angular and spatial resolution dMRI data from an extensive ex vivo cohort of 8 macaques. The independent validation with open-access dMRI and tracer data of macaques revealed the reproducibility and validity of our parcellations and their connections. The regional boundaries based on the connectivity were found to be consistent with the cytoarchitectonic boundaries, which were drawn using the Nissl-stained histological images. The new atlas, multi-modal connectomes, and the acquired dMRI and Nissl data will be released as a resource to provide new opportunities for linking multi-modal data such as MRI, tracers and histological images at micro-, meso-, and macroscopic scales 46 with MacBNA as a reference system and to promote progress in translational medicine, cross-species comparative investigations, and computational models.
TL;DR: In this paper , the authors used cross-species prefrontal-subcortical cytoarchitectonic homologies to parse anatomical abnormalities in people with OCD into higher resolution areas and neuronal networks.
Abstract: OCD has been characterized by recent data as a disorder of cognition. Recent data also show pathology in prefrontal-subcortical networks. We leveraged cross-species prefrontal-subcortical cytoarchitectonic homologies in order to parse anatomical abnormalities in people with OCD into higher resolution areas and neuronal networks. We established that the anatomical abnormalities associated with OCD predominantly reside in a neuronal network associated with emotional processing. We further provide evidence that current tests do not accurately dissociate emotion from cognition and so relying on them risks mis-stating the role of prefrontal-subcortical networks. Taken together, these findings reveal the neglect of the role of emotion in the pathophysiology of OCD.