Diffusion Tensor Imaging connectivity analysis: detecting structural alterations and their underlying substrates for Optic Ataxia in correlations with “How” stream Visual Pathways

Abstract

ABSTRACTOptic ataxia is a neurological condition that shows clinical manifestations of disturbances in visual guided hand movements on reaching for a target object. Previous studies failed to provide substantial evidences for the neural structural pathway damaged by this condition. Therefore, this study was aimed to identify the neural structural connectivity between “Visual cortex with Superior Parietal Lobule” and to correlate its functional importance, using “Diffusion Imaging fiber Tractography. The fibers were traced, and we confirmed its extension from “Visual cortex (Brodmann’s Areas 18 and 19) to Superior Parietal Lobule (Brodmann’s Area 7)”. This new observation gives an insight to understand the structural existence and functional correlations between “Visual cortex with Superior Parietal Lobule” which is involved in targeting the grasping hand movements towards a visually perceived object, called visuo-motor coordination pathway or “how” stream pathways in visual perception. The observational analysis used thirty-two healthy adults, ultra-high b-value, diffusion MRI datasets from an Open access research platform. The datasets range between 20–49 years, in both sexes, with mean age of 31.1 years. The confirmatory observational analysis process includes, datasets acquisition, pre-processing, processing, reconstruction, fiber tractography and analysis using software tools. All the datasets confirmed that the fiber structural extension between, Visual cortex to superior parietal lobe in both the sexes may be responsible for the visual spatial recognition of objects. These new fiber connectivity evidences justify the structural relevance of visual spatial recognition impairments, such as optic ataxia.