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Structural relationships between white matter tracts and positive mapping points anatomically concordant with the superior fronto-occipital fascicle. Specific tracts reconstructed by diffusion spectrum imaging were confirmed to contribute to the functions of eight positive mapping points in three-dimensional brain images. Motor positive points (white and cyan) are related with Pyramidal tract (red) (A), and sensory positive points (two yellow and one cyan) are related with somatosensory tract (green) (B). Language positive points (magenta, green, and yellow) are related with arcuate fascicle (red) and inferior fronto-occipital fascicle (cyan) (C). Each upper image is lateral view and lower is medial view.
Source publication
The presence of the superior fronto-occipital fascicle (SFOF) has been reported in the Rhesus monkey; however, it is a subject of controversy in humans. The aim of this study is to identify the SFOF using both in vitro and in vivo anatomo-functional analyses. This study consisted of two approaches. First, one acallosal brain and 12 normal postmorte...
Contexts in source publication
Context 1
... SFOF and all the points underwent left to right flip (L-R flip) (Table 3, Fig. 4, and Supplementary Fig. 4). The positive mapping sites on the SFOF included 3 language points, 3 sensory points, 1 motor point, and 1 combined motor and sensory point. None were symptoms of disconnection of the tract, but of other networks such as the pyramidal tract (Fig. 5A), somatosensory tract (Fig. 5B), and languagerelated tracts including left arcuate fascicle and left inferior fronto-occipital fascicle (Fig. 5C). Especially in language disorders induced by DES, the distribution of anomia and semantic paraphasia could explain the language networks in detail. The positive mapping points involving The ...
Context 2
... left to right flip (L-R flip) (Table 3, Fig. 4, and Supplementary Fig. 4). The positive mapping sites on the SFOF included 3 language points, 3 sensory points, 1 motor point, and 1 combined motor and sensory point. None were symptoms of disconnection of the tract, but of other networks such as the pyramidal tract (Fig. 5A), somatosensory tract (Fig. 5B), and languagerelated tracts including left arcuate fascicle and left inferior fronto-occipital fascicle (Fig. 5C). Especially in language disorders induced by DES, the distribution of anomia and semantic paraphasia could explain the language networks in detail. The positive mapping points involving The Muratoff bundle (MB) and thalamus ...
Context 3
... included 3 language points, 3 sensory points, 1 motor point, and 1 combined motor and sensory point. None were symptoms of disconnection of the tract, but of other networks such as the pyramidal tract (Fig. 5A), somatosensory tract (Fig. 5B), and languagerelated tracts including left arcuate fascicle and left inferior fronto-occipital fascicle (Fig. 5C). Especially in language disorders induced by DES, the distribution of anomia and semantic paraphasia could explain the language networks in detail. The positive mapping points involving The Muratoff bundle (MB) and thalamus peduncles (TP) fibers ran anteroposteriorly in the solid line square, while the MB, TP, and corpus callosum (CC) ...
Citations
... The IFOF connects the parietal and occipital lobes to the frontal lobe [58], and damage to this tract has been linked to language deficits and previous studies suggest that it is an essential contributor to the language network and plays a role in the visual recognition system [35,59]. The SFOF connects the frontal, parietal and occipital lobes and plays a role in spatial awareness and visual processing and the SLF connects the parietal, occipital and temporal lobes with ipsilateral frontal cortices and damage to this tract has also been linked to language deficits [60][61][62]. The ILF connects the occipital and temporal-occipital regions of the brain to the anterior temporal regions [56,63]. ...
Background
Magnetic Resonance Imaging (MRI)-based imaging techniques are useful for assessing white matter (WM) structural and microstructural integrity in the context of infection and inflammation. The purpose of this scoping review was to assess the range of work on the use of WM neuroimaging approaches to understand the impact of congenital and perinatal viral infections or exposures on the developing brain.
Methods
This scoping review was conducted according to the Arksey and O’ Malley framework. A literature search was performed in Web of Science, Scopus and PubMed for primary research articles published from database conception up to January 2022. Studies evaluating the use of MRI-based WM imaging techniques in congenital and perinatal viral infections or exposures were included. Results were grouped by age and infection.
Results
A total of 826 articles were identified for screening and 28 final articles were included. Congenital and perinatal infections represented in the included studies were cytomegalovirus (CMV) infection (n = 12), human immunodeficiency virus (HIV) infection (n = 11) or exposure (n = 2) or combined (n = 2), and herpes simplex virus (HSV) infection (n = 1). The represented MRI-based WM imaging methods included structural MRI and diffusion-weighted and diffusion tensor MRI (DWI/ DTI). Regions with the most frequently reported diffusion metric group differences included the cerebellar region, corticospinal tract and association fibre WM tracts in both children with HIV infection and children who are HIV-exposed uninfected. In qualitative imaging studies, WM hyperintensities were the most frequently reported brain abnormality in children with CMV infection and children with HSV infection.
Conclusion
There was evidence that WM imaging techniques can play a role as diagnostic and evaluation tools assessing the impact of congenital infections and perinatal viral exposures on the developing brain. The high sensitivity for identifying WM hyperintensities suggests structural brain MRI is a useful neurodiagnostic modality in assessing children with congenital CMV infection, while the DTI changes associated with HIV suggest metrics such as fractional anisotropy have the potential to be specific markers of subtle impairment or WM damage in neuroHIV.
... Traditional neuroanatomists such as the Dejerines (Dejerine & Dejerine-Klumpke, 1895), Zilles (Bürgel et al., 2006), and Pandya (Makris et al., 2007;Petrides & Pandya, 2006;Schmahmann & Pandya, 2006;Yeterian & Pandya, 2010) have endorsed the existence of the sFOF in the monkey and human brain without reservation. By contrast, fiber microdissection and dMRI-based tractographic studies have not consistently demonstrated this fiber tract in humans (Bao et al., 2017;Catani et al., 2002;Decramer et al., 2018;Forkel et al., 2014;Liu et al., 2020;Ludwig & Klingler, 1956;Meola et al., 2015;Mori, 2002;Türe et al., 1997;Wakana et al., 2004). It is clear that this remains an unresolved issue. ...
A key set of connections necessary for the most complex brain functions are the long association cortico‐cortical fiber tracts. These pathways have been described by the Dejerines and others using post mortem histological or brain dissection techniques. Given methodological limitations, these fiber connections have not been delineated completely in humans. Although the stem portions of fiber tracts have been identified in humans, their precise origins and terminations remain to be determined. By contrast, the origins and terminations as well as the stems of long cortico‐cortical association fiber pathways in monkeys have been detailed in the macaque monkey brain using experimental tract tracing methods. Deepak Pandya made major contributions to the delineation of fiber tracts in the monkey brain. In the early 1990s, he compared his observations in monkeys with the original descriptions in humans by the Dejerines. With the advent of diffusion‐weighted imaging, Dr. Pandya extended this line of investigation to the human brain with Dr. Nikos Makris. In this translational analysis of long association cortico‐cortical fiber tracts, they applied a principle of extrapolation from monkey to human. In the present study, we addressed the reasoning and the complex methodology in translating brain structural connectivity from monkey to human in one cortico‐cortical fiber tract, namely the superior fronto‐occipital fascicle, which was delineated in both species by Dr. Pandya and colleagues. Furthermore, we represented this information in the form of connectional matrices in the context of the HOA2.0‐ComPaRe framework, a homological monkey‐to‐human translational system used in neuroimaging.
... Even though this label is still available in some atlases (e.g. John Hopkins University JHU atlas (Mori et al., 2005)), several studies using different methods reject its existence Liu et al., 2020;Meola et al., 2015). ...
The brain is the most magnificent structure, and we are only at the cusp of unravelling some of its complexity. Neuroanatomy is the best tool for mapping the brain’s structural complexity. As such, neuroanatomy is not just an academic exercise; it serves our fundamental understanding of the neurobiology of cognition and improves clinical practice. A deepened anatomical understanding has advanced our conceptual grasp of the evolution of the brain, interindividual variability of cognition in health and disease, and the conceptual shift toward the emergence of cognition. For the past 20 years, diffusion imaging tractography has dramatically facilitated these advances by enabling the study of the delicate networks that orchestrate brain processes (for review, see (Thiebaut de Schotten and Forkel, 2022).
... The superior occipito-frontal fascicle is a long association white matter tract that connects the frontal and occipital cortices ( Figure 2I). The tract travels parallel to the corticospinal tracts and corpus callosum between the corticospinal tracts and the lateral ventricles, and inferiorly to the corpus callosum (294,295). Anterior and posterior to the corpus callosum, the superior occipito-frontal fascicle projects superiorly (295). ...
... The tract travels parallel to the corticospinal tracts and corpus callosum between the corticospinal tracts and the lateral ventricles, and inferiorly to the corpus callosum (294,295). Anterior and posterior to the corpus callosum, the superior occipito-frontal fascicle projects superiorly (295). ...
... Due to the location, length, and connection of the frontal and occipital cortices, the superior occipito-frontal fascicle is associated with several functions. A study of 90 awake glioma craniotomy patients found that the superior occipito-frontal fascicle had mapping points associated with specific characteristics for speech disorder (27.2%), motor disorder (24.7%), language disorder (16.1%), sensory disorder (15%), and several other functions with less distinction (295). The study also found that the superior occipito-frontal fascicle was positively associated with the visual field, visuospatial cognition, and spatial working memory (295). ...
The human brain is an exceptionally complex organ that is comprised of billions of neurons. Therefore, when a traumatic event such as a concussion occurs, somatic, cognitive, behavioral, and sleep impairments are the common outcome. Each concussion is unique in the sense that the magnitude of biomechanical forces and the direction, rotation, and source of those forces are different for each concussive event. This helps to explain the unpredictable nature of post-concussion symptoms that can arise and resolve. The purpose of this narrative review is to connect the anatomical location, healthy function, and associated post-concussion symptoms of some major cerebral gray and white matter brain regions and the cerebellum. As a non-exhaustive description of post-concussion symptoms nor comprehensive inclusion of all brain regions, we have aimed to amalgamate the research performed for specific brain regions into a single article to clarify and enhance clinical and research concussion assessment. The current status of concussion diagnosis is highly subjective and primarily based on self-report of symptoms, so this review may be able to provide a connection between brain anatomy and the clinical presentation of concussions to enhance medical imaging assessments. By explaining anatomical relevance in terms of clinical concussion symptom presentation, an increased understanding of concussions may also be achieved to improve concussion recognition and diagnosis.
... The IFOF connects the parietal and occipital lobes to the frontal lobe (51), and damage to this tract has been linked to language de cits and previous studies suggest that it is an essential contributor to the language network and plays a role in the visual recognition system (33,52). The SFOF connects the frontal, parietal and occipital lobes and plays a role in spatial awareness and visual processing and the SLF connects the parietal, occipital and temporal lobes with ipsilateral frontal cortices and damage to this tract has also been linked to language de cits (53,54,55). The ILF connects the occipital and temporal-occipital regions of the brain to the anterior temporal regions (49,56). ...
Background
Magnetic Resonance Imaging (MRI)-based imaging techniques are useful to assess white matter (WM) structural and microstructural integrity in the context of infection and inflammation. The purpose of this scoping review was to examine current existing published literature exploring WM neuroimaging approaches to understand the impact of congenital and perinatal viral infections or exposures on the developing brain.
Methods
This scoping review was conducted according to the Arksey and O’ Malley framework. A literature search was performed in Web of Science, Scopus and PubMed for primary research articles published from database conception up to January 2022. Studies evaluating the use of MRI-based WM imaging techniques in congenital and perinatal viral infections or exposures were included. Results were grouped by age and infection status.
Results
A total of 826 articles were identified for screening and 28 final articles were included. Congenital and perinatal infections represented in the included studies were cytomegalovirus (CMV) infection, human immunodeficiency virus (HIV) infection and exposure, and herpes simplex virus (HSV) infection. The MRI-based WM imaging methods represented in the included studies were structural MRI and diffusion-weighted and diffusion tensor MRI (DWI/ DTI). The most frequently reported regions with diffusion parameter group differences included the cerebellar region, corticospinal tract and association fibre WM tracts in both children with HIV infection and children who are HIV-exposed uninfected, although there were fewer studies in the latter group. In qualitative imaging studies, WM hyperintensities were the most frequently reported brain abnormality in children with CMV infection and children with HSV infection. Scoping review findings suggested that diffusion parameters have the potential to be specific markers of impairment or damage of WM in viral infections.
Conclusion
There was evidence to suggest that WM imaging techniques can play a role as diagnostic and evaluation tools, while metrics of quantitative WM imaging modalities have the potential to be specific markers of impairment or damage.
... 26 thalamic peduncles. [28][29][30][31][32][33][34][35][36][37][38][39][40][41] However, no article discussed the correlation of the superior thalamic radiation or TCT to sensory systems or its functional importance. ...
OBJECTIVE
Despite the disabling deficits of motor apraxia and sensory ataxia resulting from intraoperative injury of the superior thalamocortical tracts (TCTs), region-specific electrophysiological localization is currently lacking. Herein, the authors describe a novel TCT mapping paradigm.
METHODS
Three patients, 1 asleep and 2 awake, underwent glioma resection affecting primarily the somatosensory cortex and underlying TCT. Stimulation was performed at the median, ulnar, and posterior tibial nerves. Parameters comprised single anodal pulses (duration 200–500 μsec, 2.1–4.7 Hz) with a current ranging from 10 to 25 mA. Recordings were captured with a bipolar stimulation probe, avoiding the classic collision technique. Positive localization sites were used to tractographically reconstruct the TCT in the third case.
RESULTS
Employing one electrophysiological paradigm, the TCT was localized subcortically in all 3 cases by using a bipolar probe, peak range of 19.6–29.2 msec, trough of 23.3–34.8 msec, stimulation range of 10–25 mA. In the last case, tractographic reconstruction of the TCT validated a highly accurate TCT localization within a specific region of the posterior limb of the internal capsule.
CONCLUSIONS
The authors describe the first electrophysiological technique for intraoperative localization and protection of the TCT in both asleep and awake craniotomies with tractographic validation, while avoiding the collision paradigm. None of the above paradigms have been previously reported. More data are required to further validate this technique.
... Finally, the anatomical locations of the positive mapping sites on the 3D MNI template were reconfirmed. Each reconstruction was first constructed by R.N. and then systematically checked by a neurosurgeon (M.K.) (Liu et al. 2020). All VOIs were flipped to the left side and overlaid onto an MNI152 brain template that included the tracts of the optic radiation, the threshold of which was 0.5, based on the tractography-based white matter atlas, as reported by Rojkova et al. (Rojkova et al. 2016). ...
Brain mapping during awake craniotomy for gliomas can help preserve neurological functions, including maintenance of central and peripheral vision. However, the consecutive changes in the visual field remain unknown. We retrospectively assessed 14 patients who underwent awake craniotomy for gliomas infiltrating into the optic radiation. Cortico-subcortical direct electrical stimulation (DES) was intraoperatively applied until transient visual symptoms were elicited and recorded. The visual fields were examined consecutively in the preoperative period and postoperative subacute and chronic periods. To evaluate the anatomo-functional validity of the recordings, all DES-elicited points were overlaid onto a three-dimensional template that included the optic radiation, using voxel-based morphometry (VBM) mapping. All patients experienced visual symptoms that were classified as phosphenes, blurred vision, or hallucinations during DES, and surgical resection was limited to within the functional boundaries. In VBM, almost all the subcortical positive mapping points overlapped with the surface of the optic radiation, and the distribution of sites that induced visual phenomena in the upper or lower visual fields could be differentiated in the anatomical space. We observed no postoperative visual deficit in four patients (29%), time-dependent improvements in five out of eight patients that presented transient quadrantanopia or partial visual defect (36% out of 57%), and permanent hemianopsia (14%) in two patients with occipital lesions. Intraoperative DES that identifies and preserves optic radiation in awake craniotomy for gliomas is a reliable and effective technique to reduce risk of permanent deficits, but has a low success rate in patients with occipital involvement.
... Finally, the anatomical locations of the positive mapping sites on the 3D MNI template were recon rmed. Each reconstruction was rst constructed by R.N. and then systematically checked by a neurosurgeon (M.K.) (Liu et al. 2020). All VOIs were ipped to the left side and overlaid onto an MNI152 brain template that included the tracts of the optic radiation, the threshold of which was 0.5, based on the tractography-based white matter atlas, as reported by Rojkova et al (Rojkova et al. 2016). ...
Brain mapping during awake craniotomy for gliomas can help preserve neurological functions, including maintenance of central and peripheral vision. However, the consecutive changes in the visual field remain unknown. We retrospectively assessed 14 patients who underwent awake craniotomy for gliomas infiltrating into the optic radiation. Cortico-subcortical direct electrical stimulation (DES) was intraoperatively applied until transient visual symptoms were elicited and recorded. The visual fields were examined consecutively in the preoperative period and postoperative subacute and chronic periods. To evaluate the anatomo-functional validity of the recordings, all DES-elicited points were overlaid onto a three-dimensional template that included the optic radiation, using voxel-based morphometry (VBM) mapping. All patients experienced visual symptoms that were classified as phosphenes, blurred vision, or hallucinations during DES, and surgical resection was limited to within the functional boundaries. In VBM, almost all the subcortical positive mapping points overlapped with the surface of the optic radiation, and the distribution of sites that induced visual phenomena in the upper or lower visual fields could be differentiated in the anatomical space. We observed no postoperative visual deficit in four patients (29%), time-dependent improvements in five out of eight patients that presented transient quadrantanopia or partial visual defect (36% out of 57%), and permanent hemianopsia (14%) in two patients with occipital lesions. Intraoperative DES that identifies and preserves optic radiation in awake craniotomy for gliomas is a reliable and effective technique to avoid permanent deficit, but has a low success rate in patients with occipital involvement.
... As there is no superior fof in humans, we used this pathway, previously called the inferior fof (ifof), as the fof. 11,37 The role of the superior longitudinal fasciculus-arcuate fasciculus complex, one of the largest white matter pathways in the region connecting all sections of the opercula, is lexical, semantic, and phonological language processing in the dominant hemisphere, while perception and nonlinguistic communication occurs in the nondominant hemisphere. UF, which has a role in the ventral limbic pathway, is effective in reward-and punishment-based behaviors and decision-making. ...
Objective:
Radiological, anatomical, and electrophysiological studies have shown the insula and cerebral opercula to have extremely high functionality. Because of this complexity, interventions in this region cause higher morbidity compared to those in other areas of the brain. In most early studies of the insula and white matter pathways, insular dissection was begun after the opercula were removed. In this study, the authors examined the insula and deep white matter pathways to evaluate the insula as a whole with the surrounding opercula.
Methods:
Twenty formalin-fixed adult cerebral hemispheres were studied using fiber microdissection techniques and examination of sectional anatomy. Dissections were performed from lateral to medial, medial to lateral, inferior to superior, and superior to inferior. A silicone brain model was used to show the normal gyral anatomy. Sections and fibers found at every stage of dissection were photographed with a professional camera. MRI tractography studies were used to aid understanding of the dissections.
Results:
The relationships between the insula and cerebral opercula were investigated in detail through multiple dissections and sections. The relationship of the extreme and external capsules with the surrounding opercula and the fronto-occipital fasciculus with the fronto-orbital operculum was demonstrated. These findings were correlated with the tractography studies. Fibers of the extreme capsule connect the medial aspect of the opercula with the insula through the peri-insular sulcus. Medial to lateral dissections were followed with the removal of the central core structures, and in the last step, the medial surface of the cerebral opercula was evaluated in detail.
Conclusions:
This anatomical study clarifies our understanding of the insula and cerebral opercula, which have complex anatomical and functional networks. This study also brings a new perspective to the connection of the insula and cerebral opercula via the extreme and external capsules.
... Older dissection studies on human brains were mixed in their descriptions of this bundle (Forel 1881;Dejerine and Dejerine-Klumpke 1895;Schröder 1901). Importantly, modern human investigations, using both tractography and Klingler dissections (Türe et al. 1997;Forkel et al. 2014;Meola et al. 2015;Liu et al. 2020), have failed to replicate this structure. Instead, a structure consistent with descriptions of the SFOF can be found in individuals with agenesis of the corpus callosum, but this observation may not apply to white matter architecture more broadly Pandya 2006, 2007a;Forkel et al. 2014). ...
... Furthermore, even Schmahmann and Pandya (2006) do not identify occipital connections of SFOF; instead, the connectivity of their bundle appears quite similar to that of SLF II. Even in cases where a structure resembling accounts of SFOF can be reconstructed in humans via tratographic approaches (Makris et al. 2007;Uddin et al. 2010;Liu et al. 2020), the posterior connectivity observed is with the parietal lobe (and thus more consistent with accounts of SLF II), and not with the occipital lobe as would presumably be required of a fronto-occipital fasciculus (Mandonnet et al. 2018). One possibility is that SLF II extends more medially in the monkey than in humans, thus generating the observed tract-tracing results. ...
The functional and computational properties of brain areas are determined, in large part, by their connectivity profiles. Advances in neuroimaging and network neuroscience allow us to characterize the human brain noninvasively, but a comprehensive understanding of the human brain demands an account of the anatomy of brain connections. Long-range anatomical connections are instantiated by white matter, which itself is organized into tracts. These tracts are often disrupted by central nervous system disorders, and they can be targeted by neuromodulatory interventions, such as deep brain stimulation. Here, we characterized the connections, morphology, traversal, and functions of the major white matter tracts in the brain. There are major discrepancies across different accounts of white matter tract anatomy, hindering our attempts to accurately map the connectivity of the human brain. However, we are often able to clarify the source(s) of these discrepancies through careful consideration of both histological tract-tracing and diffusion-weighted tractography studies. In combination, the advantages and disadvantages of each method permit novel insights into brain connectivity. Ultimately, our synthesis provides an essential reference for neuroscientists and clinicians interested in brain connectivity and anatomy, allowing for the study of the association of white matter's properties with behavior, development, and disorders.
