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Identification of the central sulcus. Superior panel (a, b): the inferior part of the central sulcus (Central S) can be identified by two sets of rules on a sagittal slice passing through the anterior part of the lateral fissure (a) or on a lateral right semi-inflated representation of the cortical surface (b): from anterior to posterior (a, b) after identifying the anterior segment of the lateral fissure (Lat Fiss ant, see ), search for the inferior frontal sulcus (Inf Front S), a horizontal sulcus running just dorsal to it. The latter branches at right angles with the inferior part of the precentral sulcus (PreC S), located just anterior to the central sulcus. The inferior frontal sulcus dorsally limits the inferior frontal gyrus, made of parts orbital (or), triangular (tr) and opercular (op); from posterior to anterior (a, b) first identify the posterior tip of the lateral fissure (Lat Fiss post), surrounded by the supramarginal gyrus (Supra Marg G). The anterior limit of the supramarginal gyrus is the postcentral sulcus (PostC S), which posteriorly parallels the central sulcus. Middle panel (c, d) identification of the middle segment of the central sulcus on an axial slice (c) and semi-inflated supero-lateral view of the right hemisphere (d). The superior frontal sulcus (Sup Front S) is easily recognized as a longitudinal, continuous sulcus, which parallels the superior edge of the hemisphere. It posteriorly joins the precentral sulcus (PreC S) at a right angle. The central sulcus is located just posterior. NB: The Omega sign and increased thickness of the cortex are other signs helping the identification of the middle segment of the central sulcus. Inferior panel (e–g) identification of the superior aspect of the central sulcus. On a parasagittal slice (e) or a semi-inflated reconstruction of the surface of the right hemisphere (f, supero-medial view), the marginal part (Pars Margin) of the cingulate sulcus (Cingul S) is first identified as the ascending posterior part of the cingulate sulcus; on an axial slice (g), both marginal parts of the cingulate sulci form an anteriorly concave curve. The superior tip of the central sulcus lies just anterior to this bracket sign. Yellow indices show interlobar sulci, whereas white ones show intralobar sulci/gyri
Source publication
The precise sulcogyral localization of cortical lesions is mandatory to improve communication between practitioners and to predict and prevent post-operative deficits. This process, which assumes a good knowledge of the cortex anatomy and a systematic analysis of images, is, nevertheless, sometimes neglected in the neurological and neurosurgical tr...
Citations
... Research has even links central nervous system lesions in the GR to epilepsy seizures [44]. Located on the basal surface of the frontal lobe [45], the GR plays a critical role in memory, decision-making, and executive functions [39]. ...
Background
Distinguishing untreated major depressive disorder without medication (MDD) from schizophrenia with depressed mood (SZDM) poses a clinical challenge. This study aims to investigate differences in fractional amplitude of low-frequency fluctuations (fALFF) and cognition in untreated MDD and SZDM patients.
Methods
The study included 42 untreated MDD cases, 30 SZDM patients, and 46 healthy controls (HC). Cognitive assessment utilized the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Resting-state functional magnetic resonance imaging (rs-fMRI) scans were conducted, and data were processed using fALFF in slow-4 and slow-5 bands.
Results
Significant fALFF changes were observed in four brain regions across MDD, SZDM, and HC groups for both slow-4 and slow-5 fALFF. Compared to SZDM, the MDD group showed increased slow-5 fALFF in the right gyrus rectus (RGR). Relative to HC, SZDM exhibited decreased slow-5 fALFF in the left gyrus rectus (LGR) and increased slow-5 fALFF in the right putamen. Changes in slow-5 fALFF in both RGR and LGR were negatively correlated with RBANS scores. No significant correlations were found between remaining fALFF (slow-4 and slow-5 bands) and RBANS scores in MDD or SZDM groups.
Conclusions
Alterations in slow-5 fALFF in RGR may serve as potential biomarkers for distinguishing MDD from SZDM, providing preliminary insights into the neural mechanisms of cognitive function in schizophrenia.
... All researchers were trained in the dissection protocol before data acquisition. The sulci-gyral configuration of each cerebral hemisphere was studied before dissection to identify cortical landmarks for optimal navigation and to assess individual anatomical variations based on the reference atlases (Destrieux et al., 2017;Ono et al., 1990). ...
Despite advances in the study of the human cerebral white matter, short association fibers remain underexplored, as furthering the understanding of their anatomy has been hindered by their compact and juxtacortical character. Both magnetic resonance-based diffusion imaging and post-mortem post-cortex removal dissection meet significant difficulties in addressing the superficial white matter. In this study, we present an inside-out fiber dissection technique to assess short-association fiber anatomy in the human brain. The deep aspect of these fibers is dissectible from adjacent fasciculi, which provides a unique opportunity to characterize the human superficial structural connectivity through direct observation. This technique adds to the neuroscience armamentarium, circumventing a severe methodological obstacle, providing the anatomical substrate necessary for modeling neural circuits, and validating diffusion imaging of the superficial white matter.
Available at: https://www.liebertpub.com/doi/abs/10.1089/brain.2023.0050?af=R
Posprint: https://hal.science/hal-04539109
... The ROIs were organized into 8 ROI groups ( Fig. 2; see also Table 1). ROI assignment was based on automated parcellation of cortical gyri, implemented in the FreeSurfer software package (Destrieux et al., 2010(Destrieux et al., , 2017 and then confirmed by visual inspection of anatomical reconstruction data. For recording sites in Heschl's gyrus, delineation of the border between core auditory cortex and adjacent non-core areas [posteromedial (HGPM) and anterolateral (HGAL) portions of Heschl's gyrus, respectively] was performed in each participant using physiological criteria (Brugge et al., 2009;Nourski et al., 2016). ...
... Each recording site was assigned to one of 50 regions of interest (ROIs) based on anatomical reconstructions of electrode locations in each participant (Supplementary Figure 2). ROI assignment was based on automated cortical parcellation as implemented in the FreeSurfer software package (Destrieux et al., 2010(Destrieux et al., , 2017 and refined based on visual inspection of anatomical reconstruction data. For recording sites in Heschl's gyrus, delineation of the border between core auditory cortex and adjacent non-core areas [posteromedial (HGPM) and anterolateral (HGAL) portions, respectively] was performed in each participant using multiple physiological criteria. ...
Introduction
Cochlear implants (CIs) are the treatment of choice for severe to profound hearing loss. Variability in CI outcomes remains despite advances in technology and is attributed in part to differences in cortical processing. Studying these differences in CI users is technically challenging. Spectrally degraded stimuli presented to normal-hearing individuals approximate input to the central auditory system in CI users. This study used intracranial electroencephalography (iEEG) to investigate cortical processing of spectrally degraded speech.
Methods
Participants were adult neurosurgical epilepsy patients. Stimuli were utterances /aba/ and /ada/, spectrally degraded using a noise vocoder (1–4 bands) or presented without vocoding. The stimuli were presented in a two-alternative forced choice task. Cortical activity was recorded using depth and subdural iEEG electrodes. Electrode coverage included auditory core in posteromedial Heschl’s gyrus (HGPM), superior temporal gyrus (STG), ventral and dorsal auditory-related areas, and prefrontal and sensorimotor cortex. Analysis focused on high gamma (70–150 Hz) power augmentation and alpha (8–14 Hz) suppression.
Results
Chance task performance occurred with 1–2 spectral bands and was near-ceiling for clear stimuli. Performance was variable with 3–4 bands, permitting identification of good and poor performers. There was no relationship between task performance and participants demographic, audiometric, neuropsychological, or clinical profiles. Several response patterns were identified based on magnitude and differences between stimulus conditions. HGPM responded strongly to all stimuli. A preference for clear speech emerged within non-core auditory cortex. Good performers typically had strong responses to all stimuli along the dorsal stream, including posterior STG, supramarginal, and precentral gyrus; a minority of sites in STG and supramarginal gyrus had a preference for vocoded stimuli. In poor performers, responses were typically restricted to clear speech. Alpha suppression was more pronounced in good performers. In contrast, poor performers exhibited a greater involvement of posterior middle temporal gyrus when listening to clear speech.
Discussion
Responses to noise-vocoded speech provide insights into potential factors underlying CI outcome variability. The results emphasize differences in the balance of neural processing along the dorsal and ventral stream between good and poor performers, identify specific cortical regions that may have diagnostic and prognostic utility, and suggest potential targets for neuromodulation-based CI rehabilitation strategies.
... Automated identification and parcellation of the cortical surface within T1-weighted images were carried out with FreeSurfer [154,155]. Electrodes were assigned anatomical labels within the parcellation scheme of Destrieux and colleaguesAU : Pleasenotethatallinstancesof }etal:}inthemaintexthavebeenchangedto}andcol [156,157], according to the label of the nearest vertex (within the T1 image space) of the cortical surface mesh generated by FreeSurfer. Labeling was visually inspected and corrected whenever the automated parcellation did not conform to expected gyral boundaries. ...
... To pool data across participants, the dimensionality of connectivity matrices was reduced by assigning electrodes to one of 58 ROIs organized into 6 ROI groups (see Fig 1; S2 and S3 Tables) based upon anatomical reconstructions of electrode locations in each participant. For subdural arrays, ROI assignment was informed by automated parcellation of cortical gyri [156,157] as implemented in the FreeSurfer software package. For depth arrays, ROI assignment was informed by MRI sections along sagittal, coronal, and axial planes. ...
Understanding central auditory processing critically depends on defining underlying auditory cortical networks and their relationship to the rest of the brain. We addressed these questions using resting state functional connectivity derived from human intracranial electroencephalography. Mapping recording sites into a low-dimensional space where proximity represents functional similarity revealed a hierarchical organization. At a fine scale, a group of auditory cortical regions excluded several higher-order auditory areas and segregated maximally from the prefrontal cortex. On mesoscale, the proximity of limbic structures to the auditory cortex suggested a limbic stream that parallels the classically described ventral and dorsal auditory processing streams. Identities of global hubs in anterior temporal and cingulate cortex depended on frequency band, consistent with diverse roles in semantic and cognitive processing. On a macroscale, observed hemispheric asymmetries were not specific for speech and language networks. This approach can be applied to multivariate brain data with respect to development, behavior, and disorders.
... All recording sites were assigned an anatomical label based on the Destrieux atlas implemented as individualized and automated parcellation of cortical gyri using the Freesurfer software package (52,53). Further, all cortical recording sites were assigned a brain network label based on the Yeo7 network parcellation available in standard MNI space (22). ...
Physical exercise acutely improves hippocampal-based learning and memory in rodents and humans. While animal studies have mainly offered cellular- and synaptic-level accounts of these effects, human neuroimaging studies show that exercise improves hippocampal-cortical connectivity at the macroscale level. However, the neurophysiological basis for exercise-induced effects on human hippocampal-cortical circuits remains unknown. A growing body of evidence supports the critical role of hippocampal sharp wave-ripples (SWRs) in learning and memory. Moreover, recent studies suggest that the coupling between ripples in the hippocampus and neocortex reflect acute modulations in inter-regional connectivity required by mnemonic processes. Here, we examine the hypothesis that exercise modulates hippocampal SWR events and their coupling with ripples in other cortical areas. We performed intracranial recordings in neurosurgery patients during awake resting state, before and after one session of aerobic exercise. Exercise elicited an increase in ripple rate and duration in mesio-temporal areas (hippocampus, amygdala and parahippocampal gyrus). These changes in ripple features were also observed in the limbic and the default mode (DMN) networks. Furthermore, after exercise, we observed an increase in coupling and phase synchrony between ripples in these two networks and hippocampal SWRs. Our results elucidate the potential mechanisms by which aerobic exercise elicits its reported short-term effects in cognition. Further investigations are needed to explore how these exercise-induced acute modulations contribute to long-term changes in neural plasticity.
Significance Statement
Physical activity is a modifiable lifestyle factor that improves cognitive function and prevents age-related cognitive decline. Even one session of exercise can enhance hippocampal-based memory and learning. However, the neurophysiological mechanisms by which exercise acutely affects human cognition remain unknown. Using intracranial recordings in neurosurgical patients we show that the hippocampus and neocortex often synchronize their activities via high-frequency neural synchrony events known as ripples. After exercise, hippocampal and neocortical ripples were prolonged and emerged more frequently. Moreover, hippocampal and neocortical ripples exhibited increased coupling and phase synchrony. These effects were neocortical region-specific, favoring structures of the limbic and default mode networks. Ultimately, our results shed light on the mechanisms behind the preventive and therapeutic potential of exercise interventions.
... Near the connection between the isthmus of the cingulate gyrus and splenium of the corpus callosum, the marginal branch of the cingulate sulcus reaches the superior end of the hemisphere [33]. According to Terminologia Neuroanatomica [34], we did delineation of the ventral and dorsal borders of the CS in the Cartesian coordinate plane with the center at the level of Monro's interventricular foramen. ...
Cortical folding of the anterior cingulate cortex (ACC), particularly the cingulate (CS) and the paracingulate (PCS) sulci, represents a neurodevelopmental marker. Deviations in in utero development in schizophrenia can be traced using CS and PCS morphometry. In the present study, we measured the length of CS, PCS, and their segments on T1 MRI scans in 93 patients with first- episode schizophrenia and 42 healthy controls. Besides the length, the frequency and the left-right asymmetry of CS/PCS were compared in patients and controls. Distribution of the CS and PCS morphotypes in patients was different from controls. Parcellated sulcal pattern CS3a in the left hemisphere was longer in patients (53.8 ± 25.7 mm vs. 32.7 ± 19.4 mm in controls, p < 0.05), while in CS3c it was reversed—longer in controls (52.5 ± 22.5 mm as opposed to 36.2 ± 12.9 mm, n.s. in patients). Non parcellated PCS in the right hemisphere were longer in patients compared to controls (19.4 ± 10.2 mm vs. 12.1 ± 12.4 mm, p < 0.001). Therefore, concurrent presence of PCS1 and CS1 in the left hemisphere and to some extent in the right hemisphere may be suggestive of a higher probability of schizophrenia.
... In addition, the risk of PTSD and ability to handle psychological trauma can be questioned [114] [115]. [76,77]. d Desikan-Killiany Atlas, DKTatlas [78]. ...
Brain injury — the younger the patient — the more plagued and trouble from neglect anddifficulties with logical separation of physical and psychological trauma.Whereof intelligence is assumed to involve good—general neurological health—unless savan-tism is involved. Here we expose to what extreme extents psychopathology is clinged to.Risks of toxic neurological reactions from medications ignored in support of activity thatcan halt, prevent and damage stages of rehabilitation and reparation of injuries for patientswith expected—irregular—cognitive and psychosocial development.**Result**: Traumatic Brain Injury must always be documented with burden to respect, followup and suspect it — to counteract hopes, dreams and wishes on behalf of nurturing andpersonal experiences of those supposed to help and document, so society actually have aright to be considerate and give preferential treatment and exceptions. For a patient groupespecially vulnerable to maltreatment and malpractice, good intentions rarely leading to anawakening of unhealthy patient relations with risk of creating them.
... We focused, in particular, on anatomical and laboratory papers assessing the orientation of FAT fibers and their cortical origins/terminations through both fiber dissection and DTI studies on humans only. Cortical connections were assessed as described by Destrieux et al. (2017) according to the Terminologia Anatomica. We identified 343 articles by database screening, 77 of which were retained after filtering (Figure 1). ...
Knowledge of both the spatial organization and functions of white-matter fiber tracts is steadily increasing. We report here the anatomy and functions of the frontal aslant tract (FAT) in the non-dominant hemisphere (usually the right hemisphere). Despite the structural symmetry between the right and left FAT, these two tracts seem to display functional asymmetry, with several brain functions in common, but others, such as visuospatial and social cognition, music processing, shifting attention or working memory, more exclusively associated with the right FAT. Further studies are required to determine whether damage to the right FAT causes permanent cognitive impairment. Such studies will constitute the best means of testing whether this tract is a critical pathway that must be taken into account during neurosurgical procedures and the essential tasks to be incorporated into intraoperative monitoring during awake craniotomy.
... Distance between OSP of horizontal portion of the lateral sulcus and the tragus was measured in a coronal cut showing both structures (Fig. 1). Central sulcus was delimitated by the Superior Rolandic Point (SRoP) cranially in front of the marginal part according to Destrieux et al. and the Inferior Rolandic Point (IRoP) caudally, according to Reis et al. [6,13]. Distance between OSP of the nasion and OSP of the SRoP was measured on a MIP sagittal cut showing both structures. ...
Purpose
In a previous cadaveric work, we identified and described useful and reproducible surface skin landmarks to lateral sulcus, central sulcus and preoccipital notch. Potential limitations of this cadaveric study have been raised. Thus, the objective of this study was to confirm radiologically the accuracy of these previously described surface skin landmarks on brain magnetic resonance imaging (MRI) of healthy subjects.
Methods
Healthy adult volunteers underwent a high-resolution brain MRI and measurements of the orthogonal skin projection (OSP) of the anterior sylvian point (AsyP), the superior Rolandic point (SroP) and the parietooccipital sulcus were made from nasion, zygomatic bone and inion, respectively. These measures were compared to our previous cadaveric findings.
Results
Thirty-one healthy volunteers were included. ASyP was 33 ± 2 mm above the zygomatic arch, and 32.3 ± 3 mm behind the orbital rim. The lateral sulcus was 63.5 ± 4 mm above the tragus. The SRoP was 196.9 ± 6 mm behind the nasion. The superior point of the parietooccipital sulcus was 76.0 ± 4 mm above the inion. These measurements are comparable to our previously described cadaveric findings.
Conclusion
We here described three useful, simple and reproducible surface skin landmarks to lateral, central and parietooccipital sulci. Knowledge of these major landmarks is mandatory for Neurosurgical practice, especially in an emergency setting.
