Robust estimation of sulcal morphology

Abstract

12While it is well established that cortical morphology differs in relation to a variety of 13 inter-individual factors, it is often characterized using estimates of volume, thickness, 14 surface area, or gyrification. Here we developed a computational approach for 15 estimating sulcal width and depth that relies on cortical surface reconstructions output 16 by FreeSurfer. While other approaches for estimating sulcal morphology exist, studies 17 often require the use of multiple brain morphology programs that have been shown to 18 differ in their approaches to localize sulcal landmarks, yielding morphological 19 estimates based on inconsistent boundaries. To demonstrate the approach, sulcal 20 morphology was estimated in three large sample of adults across the lifespan, in 21 relation to aging. A fourth sample is additionally used to estimate test-retest reliability 22 of the approach. This toolbox is now made freely available as supplemental to this 23 paper: https://cmadan.github.io/calcSulc/. 24 25

Age‐related decrements in cortical gyrification: Evidence from an accelerated longitudinal dataset

“…Using current automated methods, sulcal morphology can also be quantitatively measured, where the width and depth of major sulci can be identified and estimated (e.g., Kochunov et al, 2005; Madan, 2019a). Across a number of studies and samples (albeit generally with much smaller samples), sulcal morphology has been reliably associated with age‐related differences (Jin et al., 2018; Kochunov et al, 2005; Li et al., 2011; Liu et al., 2010, 2013; Madan, 2019a; Rettmann et al., 2006; Shen et al., 2018). The work presented here provides additional specificity in how gyrification appears to decrease with age, a step toward understanding the underlying mechanism.…”

“…Sulcal morphology, width, and depth were estimated for 16 major sulci, using the calcSulc toolbox (Madan, 2019a). The sulci are the central, post‐central, superior frontal, inferior frontal, parieto‐occipital, occipito‐temporal, middle occipital and lunate, and marginal part of the cingulate sulci, in both the left and right hemispheres.…”

Overlooked tertiary sulci serve as a meso-scale link between microstructural and functional properties of human lateral prefrontal cortex

“…The three pmfs sulci have the smallest surface area of all sulci in LPFC. Bottom: Same layout as above, but for sulcal depth (mm), as calculated from a recent algorithm(Madan, 2019) . The three pmfs sulci are the shallowest of the LPFC sulci measured here.The pmfs-p, pmfs-i, and pmfs-a are anatomically dissociable and reflect a larger rostro-caudal myelination gradient in LPFCWhile the pmfs-p, pmfs-i, and pmfs-a are morphologically distinct from surrounding sulci…”

Fast uncertainty quantification of tracer distribution in the brain interstitial fluid with multilevel and quasi Monte Carlo

“…Consequently, brain surface regions such as the different gyri that are closer to each other than the field correlation length, become correlated even if separated by a sulcus. Since the average sulcal width is estimated to range between 1.5 and 3 mm in humans, 44,74 this aspect does not play a role for the velocity field ( λ ≈ 1 mm), but for the diffusion coefficient it may ( λ = 1 cm). We expect global quantities (eg, Q g and Q w ) and local quantities depending on white matter regions which are far from the brain surface (eg, q w ) to be largely unaffected by this modeling choice.…”