Search results
Found 21102 matches for
Human blindsight is mediated by an intact geniculo-extrastriate pathway
<jats:p>Although damage to the primary visual cortex (V1) causes hemianopia, many patients retain some residual vision; known as blindsight. We show that blindsight may be facilitated by an intact white-matter pathway between the lateral geniculate nucleus and motion area hMT+. Visual psychophysics, diffusion-weighted magnetic resonance imaging and fibre tractography were applied in 17 patients with V1 damage acquired during adulthood and 9 age-matched controls. Individuals with V1 damage were subdivided into blindsight positive (preserved residual vision) and negative (no residual vision) according to psychophysical performance. All blindsight positive individuals showed intact geniculo-hMT+ pathways, while this pathway was significantly impaired or not measurable in blindsight negative individuals. Two white matter pathways previously implicated in blindsight: (i) superior colliculus to hMT+ and (ii) between hMT+ in each hemisphere were not consistently present in blindsight positive cases. Understanding the visual pathways crucial for residual vision may direct future rehabilitation strategies for hemianopia patients.</jats:p>
PainNetworks: a web-based resource for the visualisation of pain-related genes in the context of their network associations.
Hundreds of genes are proposed to contribute to nociception and pain perception. Historically, most studies of pain-related genes have examined them in isolation or alongside a handful of other genes. More recently the use of systems biology techniques has enabled us to study genes in the context of the biological pathways and networks in which they operate. Here we describe a Web-based resource, available at http://www.PainNetworks.org. It integrates interaction data from various public databases with information on known pain genes taken from several sources (eg, The Pain Genes Database) and allows the user to examine a gene (or set of genes) of interest alongside known interaction partners. This information is displayed by the resource in the form of a network. The user can enrich these networks by using data from pain-focused gene expression studies to highlight genes that change expression in a given experiment or pairs of genes showing correlated expression patterns across different experiments. Genes in the networks are annotated in several ways including biological function and drug binding. The Web site can be used to find out more about a gene of interest by looking at the function of its interaction partners. It can also be used to interpret the results of a functional genomics experiment by revealing putative novel pain-related genes that have similar expression patterns to known pain-related genes and by ranking genes according to their network connections with known pain genes. We expect this resource to grow over time and become a valuable asset to the pain community.
Vascular Density and Retinal Function in patients with Retinitis Pigmentosa evaluated by swept-source OCT angiography and microperimetry.
PURPOSE: To determine the retinal and choroidal vessel density in the macular area with OCT angiography (SS-OCTA) in patients affected by retinitis pigmentosa (RP), to compare their data with healthy subjects, and to study a possible morphofunctional correlation by microperimetry (MP1). METHODS: 40 eyes of 40 patients affected by RP and 24 eyes of 24 healthy subjects were included in the study. Manually moving down the segmentation line of the SS-OCTA we have evaluated the vessel density for the superficial retinal plexus, deep retinal plexus, choriocapillaris and 3 levels of choroid. RESULTS: Linear regression analyses were performed of retinal structure and function. No significant correlation was detected in any case (R square = 0, p>0.05). A comparison between RP and healthy control revealed a significant reduction in SS-OCTA mean capillary density in the RP group (p=0.0011). This relationship was consistent across vascular layers (p=0.2413). A significant association between the capillary density of the various vascular complexes was detected within individual eyes (p<0.0001). CONCLUSIONS: This study represents the first study comparing MP1 and SS-OCTA data with the largest cohort of patients. RP patients showed a reduction in both the retinal and choroidal vascular network in the macular area compared to healthy subjects.
False discovery rate control for grouped or discretely supported p-values with application to a neuroimaging study
© 2019 Institut d'Estadistica de Catalunya. All rights reserved. False discovery rate (FDR) control is important in multiple testing scenarios that are common in neuroimaging experiments, and p-values from such experiments may often arise from some discretely supported distribution or may be grouped in some way. Two situations that may lead to discretely supported distributions are when the p-values arise from Monte Carlo or permutation tests are used. Grouped p-values may occur when p-values are quantized for storage. In the neuroimaging context, grouped p-values may occur when data are stored in an integer-encoded form. We present a method for FDR control that is applicable in cases where only p-values are available for inference, and when those p-values are discretely supported or grouped. We assess our method via a comprehensive set of simulation scenarios and find that our method can outperform commonly used FDR control schemes in various cases. An implementation to a mouse imaging data set is used as an example to demonstrate the applicability of our approach.