Anatomy and White Matter Connections of the Superior Parietal Lobule

Abstract

BACKGROUND The superior parietal lobule (SPL) is involved in somatosensory and visuospatial integration with additional roles in attention, written language, and working memory. A detailed understanding of the exact location and nature of associated white matter tracts could improve surgical decisions and subsequent postoperative morbidity related to surgery in and around this gyrus. OBJECTIVE To characterize the fiber tracts of the SPL based on relationships to other well-known neuroanatomic structures through diffusion spectrum imaging (DSI)-based fiber tracking validated by gross anatomical dissection as ground truth. METHODS Neuroimaging data of 10 healthy, adult control subjects was obtained from a publicly accessible database published in Human Connectome Project for subsequent tractographic analyses. White matter tracts were mapped between both cerebral hemispheres, and a lateralization index was calculated based on resultant tract volumes. Post-mortem dissections of 10 cadavers identified the location of major tracts and validated our tractography results based on qualitative visual agreement. RESULTS We identified 9 major connections of the SPL: U-fiber, superior longitudinal fasciculus, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, middle longitudinal fasciculus, extreme capsule, vertical occipital fasciculus, cingulum, and corpus callosum. There was no significant fiber lateralization detected. CONCLUSION The SPL is an important region implicated in a variety of tasks involving visuomotor and visuospatial integration. Improved understanding of the fiber bundle anatomy elucidated in this study can provide invaluable information for surgical treatment decisions related to this region.

A connectivity model of the anatomic substrates underlying Gerstmann syndrome

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Recent-onset and persistent tinnitus: Uncovering the differences in brain activities using resting-state functional magnetic resonance imaging technologies

“…As a critical component of the VAN, the right MFG serves as a convergence center for the DAN and VAN by working as a circuit breaker to interrupt ongoing endogenous attentional processes in the DAN and reorient attention to exogenous stimuli (Japee et al, 2015;Briggs et al, 2021). Furthermore, the right MFG actively engages in reorienting distinctive signals from unexpected locations (Carter et al, 2006).…”

Recent-Onset and Persistent Tinnitus: Uncover the Differences in Brain Activities using Resting-State Functional Magnetic Resonance Imaging Technologies

“…Since the SFG acts as a critical component of the superior parietal lobule (SPL), the SPG demonstrates a strong connection with the occipital lobe and involves somatosensory and visuospatial stimuli integration, written language, and working memory (Berlucchi & Vallar, 2018). Existing literature also reported SPG’s implications in shifting attention between visual targets and spatial-related attention shifts state (Lin et al, 2021). Our findings revealed no significant difference between the functional connectivity level between the ROT and PT group.…”