Influence of accessory sulci of the frontoparietal operculum on gray matter quantification

Abstract

Introduction: The perisylvian region is the cortical core of language and speech. Several accessory sulci have been described in this area, whose presence could modify the results of the automatic quantification of gray matter by popularly used software. This study aimed to assess the expression of accessory sulci in the frontoparietal operculum (FPO) and to evaluate their influence on the gray matter volume estimated by an automatic parcellation of cortical gyri and sulci.Methods: Brain MRI scans of 100 healthy adult volunteers were visually analyzed. The existence of the triangular and diagonal sulci, and the number of accessory sulci in the frontoparietal operculum, were assessed on T1 images. Also, the gray matter volume of gyri and sulci was quantified by an automatized parcellation method. Interhemispheric differences in accessory sulci were evaluated with Chi-square and Wilcoxon paired tests. The effects of the hemisphere, sex, age, total intracranial volume, and accessory sulci on morphometric variables were assessed by linear models.Results: These sulci were found in more than half of the subjects, mostly in the left hemisphere, and showed a significant effect on the gray matter content of the FPO. In particular, the volume of the inferior frontal sulcus, pars opercularis of the inferior frontal gyrus, horizontal ramus of the lateral sulcus, angular gyrus, and postcentral gyrus showed a significant influence on the presence of accessory sulci.Discussion: The prevalence of tertiary sulci in the FPO is high, although their meaning is not yet known. Therefore, they should be considered to reduce the risk of misclassifications of normal variation.

Hemispheric asymmetries in cortical grey matter of gyri and sulci in modern human populations from South America

“…A possible explanation for such discrepancies is that the longer left lateral sulcus is associated with a concomitant reduction of the angular gyrus in the inferior parietal lobe and the middle and superior occipital gyri in the left hemisphere. The preferential presence of additional sulci in one hemisphere could also contribute to an increase in the volume or surface area of the region (Keller et al., 2009; Vallejo‐Azar et al., 2023). In the parietal lobe, we also found different directions of asymmetry for the subparietal sulcus, with a rightward asymmetry, and the surrounding precuneus and posterior cingulate cortex that were larger in the left hemisphere (Kong et al., 2018).…”

Neuroanatomical and functional dissociations between variably present anterior lateral prefrontal sulci

“…Li et al, 2015;Lopez-Persem et al, 2019;Miller, Voorhies, et al, 2021;Sanides, 1964;Troiani et al, 2016Troiani et al, , 2020Weiner, 2019;Willbrand, Parker, et al, 2022). Intriguingly, some tertiary sulci are present in every brain, while others are not (Amiez et al, 2019;Hathaway et al, 2023;Malikovic et al, 2012;Miller et al, 2020;Miller, Voorhies, et al, 2021;Nakamura et al, 2020;Paus et al, 1996;Petrides, 2019;Vallejo-Azar et al, 2022;Willbrand, Parker, et al, 2022;. In the present study, we focus on the morphological, architectural, and functional features of variably present sulci in anterior LPFC-the dorsal (pimfs-d) and ventral (pimfs-v) components of the paraintermediate frontal sulcus (pimfs), respectively.…”

Neuroanatomical and Functional Dissociations between Variably Present Anterior Lateral Prefrontal Sulci

“…A growing body of recent work demonstrates the utility of studying small, shallow, and variable sulci (often referred to as tertiary sulci; Armstrong, Schleicher, Omran, Curtis, & Zilles, 1995;Welker, 1990;Chi, Dooling, & Gilles, 1977;Sanides, 1964) for understanding the anatomical and functional organization of association cortices, including LPFC ( Willbrand, Parker, et al, 2022;Amiez et al, 2013Amiez et al, , 2021Miller, Voorhies, Lurie, D'Esposito, & Weiner, 2021;Troiani, Patti, & Adamson, 2020;Lopez-Persem, Verhagen, Amiez, Petrides, & Sallet, 2019;Weiner, 2019;Troiani, Dougherty, Michael, & Olson, 2016;Li, Sescousse, Amiez, & Dreher, 2015;Amiez & Petrides, 2014;Sanides, 1964). Intriguingly, some tertiary sulci are present in every brain, whereas others are not (Hathaway et al, 2023;Vallejo-Azar et al, 2022;Willbrand, Parker, et al, 2022;Willbrand, Voorhies, Yao, Weiner, & Bunge, 2022;Miller, Voorhies, et al, 2021;Miller et al, 2020;Nakamura, Nestor, & Shenton, 2020;Amiez et al, 2019;Petrides, 2019;Malikovic et al, 2012;Paus et al, 1996). In the present study, we focus on the morphological, architectural, and functional features of variably present sulci in anterior LPFC-the dorsal (pimfs-d) and ventral (pimfs-v) components of the paraintermediate frontal sulcus (pimfs), respectively.…”