DOI: 10.5061/dryad.6wwpzgn4x
title: The superior frontal sulcus in the human brain – Morphology and probability maps

description: The superior frontal sulcus (SFS) is a major sulcus on the dorsolateral
 frontal cortex that defines the lateral limit of the superior frontal
 gyrus. Caudally, it originates near the superior precentral sulcus (SPRS)
 and rostrally, it terminates near the frontal pole. The advent of
 structural neuroimaging has revealed that this primary sulcus shows
 significant variability below the surface which is not captured by the
 classic sulcal maps. The present investigation examined the morphological
 variability of the SFS in 50 individual magnetic resonance imaging (MRI)
 scans of the human brain that were registered to the Montreal Neurological
 Institute (MNI) standard stereotaxic space. Two primary morphological
 patterns were identified: i) the SFS was classified as either a continuous
 sulcus or ii) the SFS was a complex of sulcal segments. Further, the SFS
 showed a high probability of merging with neighboring sulci on the
 superior and middle frontal gyri, and these patterns were documented. In
 addition, the morphological variability and spatial extent of the SFS were
 quantified using volumetric and surface spatial probability maps. The
 results from the current investigation provide an anatomical framework for
 understanding the sulcal morphology of the SFS, which is critical for the
 interpretation of structural and functional neuroimaging data in the
 dorsolateral frontal region, as well as for improving the accuracy of
 neurosurgical interventions.  
description: Volumetric and Surface Spatial Probability Maps for the Superior Frontal
 Sulcus of the Human Brain K. Drudik, M. Petrides Spatial probability maps
 can be used by researchers to superimpose individual subject functional
 activity peaks on the probability maps to faciliate the identification of
 sulci found within the dorsolateral frontal cortex. The volumetric
 probability maps should be overlaid onto the recent Montreal Neurological
 Institute average stereotaxic template (MNI152 2009c asymmetric template).
 The software pacakage, DISPLAY (MacDonald 1996; Vincent et al. 2016), can
 be used for visualization. The surface probability maps should visualized
 using the open-access pipeline FreeSurfer (Dale et al. 1999; Fischl et al.
 1999a, b). The surface probability mapps should be overlaid onto the pial
 surface of FreeSurfer's average surface template, fsaverage. Files
 included: * surface\_type1\_lh.mgz: Surface probability map for Type I
 superior frontal sulcus in the left hemisphere * surface\_type1\_rh.mgz:
 Surface probability map for Type I superior frontal sulcus in the right
 hemisphere * surface\_type2\_lh.mgz: Surface probability map for Type II
 superior frontal sulcus in the left hemisphere * surface\_type2\_rh.mgz:
 Surface probability map for Type II superior frontal sulcus in the right
 hemisphere * volume\_type1\_lh.mnc: Volumetric probability map for Type I
 superior frontal sulcus in the left hemisphere * volume\_type1\_rh.mnc:
 Volumetric probability map for Type I superior frontal sulcus in the right
 hemisphere * volume\_type2\_lh.mnc: Volumetric probability map for Type II
 superior frontal sulcus in the left hemisphere * volume\_type2\_rh.mnc:
 Volumetric probability map for Type II superior frontal sulcus in the
 right hemisphere