Herbert Major on the insula: An early depiction of von Economo neurones?

Herbert Major (1850-1921) undertook histopathological studies of human and non-human primate brains at the West Riding Lunatic Asylum in Wakefield, England, during the 1870s. Two of his papers specifically investigated the structure of the island of Reil, or insula, "with the view of ascertaining its exact structure". In addition to describing and illustrating its lamination as six-layered, Major also identified "spindle-shaped" cells in the lower layers of human brains, but not in non-human primates. His written description, including measurements of cell body size, and illustration are suggestive that these were the neurones later described in the frontoinsular and anterior cingulate cortex by Constantin von Economo and Georg N. Koskinas and which were subsequently given the eponym "von Economo neurones". von Economo noted that this special neuronal type had been previously seen by Betz (1881), Hammarberg (1895), and Ramón y Cajal (1899-1904), but he did not mention Major's works. Major also ascribed linguistic functions to the insula. Hence, with respect to both anatomical and physiological features, Major may have pre-empted the findings of later research on this structure.

User acceptance of neuroanatomy virtual reality course: Contrasting views between undergraduate and postgraduate students.

Virtual Reality (VR) offers cost-efficient and effective tools for spatial 3-dimensional neuroanatomy learning. Enhancing users-system relationship is necessary for successful adoption of the system. The current study aimed to evaluate students' acceptance of VR for neuroanatomy. An exploratory qualitative case study based on Unified Theory of Acceptance and Use of Technology (UTAUT) framework carried out at [details omitted for double-anonymized peer review]. Participants in this study were students participating in a VR session, followed by a semi-structured interview. Deductive framework analysis employed to retrieve students' perspective and experience. A total of six undergraduate and 13 postgraduate students participated in this study. The following UTAUT constructs validated to be significant: Performance Expectancy, Effort Expectancy and Facilitating Conditions. System usability, depth of lesson and hardware optimizations are among concern for further improvements. In conclusion, students are accepting VR as a neuroanatomy learning resource. The findings of this research highlight the importance of system performance and user-centred approach in technology development for educational purposes.

[Sir Charles Bell (1774-1842) and his contribution to neurology (the 250th anniversary of the birth)]. / Ser Charl'z Bell (1774­1842) i ego vklad v nevrologiyu (k 250-letiyu so dnya rozhdeniya).

Sir Charles Bell (1774-1842) is Scottish physiologist, surgeon, artist, philosopher and anatomist. Throughout his professional career, Charles Bell made a number of important discoveries and published a large number of scientific papers. Bell first presented a detailed description of the clinical picture of facial palsy (later named after him) and a number of other neurological disorders, as well as important information about referred pain and reciprocal inhibition. Exploring the physical expression of emotions, Bell described the anatomical basis of facial expressions, which became the basis and incentive for Charles Darwin's work in this direction. Being a talented artist, the scientist himself illustrated his publications. Bell was one of the first to integrate scientific research in neuroanatomy with clinical practice. His most significant discoveries are collected in the book «The Nervous System of the Human Body¼ (1830). A number of neurological conditions and patterns were named after him.

Neuroanatomical, transcriptomic, and molecular correlates of math ability and their prognostic value for predicting learning outcomes.

Foundational mathematical abilities, acquired in early childhood, are essential for success in our technology-driven society. Yet, the neurobiological mechanisms underlying individual differences in children's mathematical abilities and learning outcomes remain largely unexplored. Leveraging one of the largest multicohort datasets from children at a pivotal stage of knowledge acquisition, we first establish a replicable mathematical ability-related imaging phenotype (MAIP). We then show that brain gene expression profiles enriched for candidate math ability-related genes, neuronal signaling, synaptic transmission, and voltage-gated potassium channel activity contributed to the MAIP. Furthermore, the similarity between MAIP gene expression signatures and brain structure, acquired before intervention, predicted learning outcomes in two independent math tutoring cohorts. These findings advance our knowledge of the interplay between neuroanatomical, transcriptomic, and molecular mechanisms underlying mathematical ability and reveal predictive biomarkers of learning. Our findings have implications for the development of personalized education and interventions.

Evolution of understanding.

From the time of Hippocrates to the early 19th century, knowledge advanced but that was an uneven process. Anatomy was basically defined by Galen and remained cast in stone until the early 16th century. Neuroanatomy was described by Galen but had little practical value, as brain surgery was not possible. The anatomy of the cranium was known and was largely correct. Care was taken to avoid the frontal air sinuses and the venous sinuses and the temporal region. The role of the brain in consciousness was not understood. It was considered the seat of the soul but there was a lack of understanding that damage to it could induce clinical symptoms such as stupor or paralysis. These were variously attributed to injuries to the meninges or the bone. This error was finally corrected in the 18th century when the brain was identified as responsible for much of the clinical disturbance following cranial trauma. All awareness that post traumatic neurological deficit was contralateral was ignored until the late 18th century, although several authors noted it. Likewise, the presence of CSF had to wait until the 18th century until it was recognized. Fissures were treated with trepanation, because of a perceived risk of infection developing between the bone and the dura. Depressed fracture fragments were elevated, replaced, or removed according to the details of the injury. Finally, for centuries surgeons blocked patients ears to reduce the sound of drilling, despite the fact that such a blocking would amplify the noise.

GRAVEN: a database of teaching method that applies gestures to represent the neurosurgical approach's blood vessels and nerves.

BACKGROUND: In this era of rapid technological development, medical schools have had to use modern technology to enhance traditional teaching. Online teaching was preferred by many medical schools. However due to the complexity of intracranial anatomy, it was challenging for the students to study this part online, and the students were likely to be tired of neurosurgery, which is disadvantageous to the development of neurosurgery. Therefore, we developed this database to help students learn better neuroanatomy. MAIN BODY: The data were sourced from Rhoton's Cranial Anatomy and Surgical Approaches and Neurosurgery Tricks of the Trade in this database. Then we designed many hand gesture figures connected with the atlas of anatomy. Our database was divided into three parts: intracranial arteries, intracranial veins, and neurosurgery approaches. Each section below contains an atlas of anatomy, and gestures represent vessels and nerves. Pictures of hand gestures and atlas of anatomy are available to view on GRAVEN ( www.graven.cn ) without restrictions for all teachers and students. We recruited 50 undergraduate students and randomly divided them into two groups: using traditional teaching methods or GRAVEN database combined with above traditional teaching methods. Results revealed a significant improvement in academic performance in using GRAVEN database combined with traditional teaching methods compared to the traditional teaching methods. CONCLUSION: This database was vital to help students learn about intracranial anatomy and neurosurgical approaches. Gesture teaching can effectively simulate the relationship between human organs and tissues through the flexibility of hands and fingers, improving anatomy interest and education.

Illustrated Neuroanatomy of Ctenophores: Immunohistochemistry.

Ctenophores or comb jellies are representatives of an enigmatic lineage of early branching metazoans with complex tissue and organ organization. Their biology and even microanatomy are not well known for most of these fragile pelagic and deep-water species. Here, we present immunohistochemical protocols successfully tested on more than a dozen ctenophores. This chapter also illustrates neural organization in several reference species of the phylum (Pleurobrachia bachei, P. pileus, Mnemiopsis leidyi, Bolinopsis microptera, Beroe ovata, and B. abyssicola) as well as numerous ciliated structures in different functional systems. The applications of these protocols illuminate a very complex diversification of cell types comparable to many bilaterian lineages.

Investigating the impact of remote neuroanatomy education during the COVID-19 pandemic using online examination performance in a National Undergraduate Neuroanatomy Competition.

Neuroanatomy is a notoriously challenging subject for medical students to learn. Due to the coronavirus disease-19 (COVID-19) pandemic, anatomical education transitioned to an online format. We assessed student performance in, and attitudes toward, an online neuroanatomy assessment compared to an in-person equivalent, as a marker of the efficacy of remote neuroanatomy education. Participants in the National Undergraduate Neuroanatomy Competition (NUNC) 2021 undertook two online examinations: a neuroanatomically themed multiple-choice question paper and anatomy spotter. Students completed pre- and post-examination questionnaires to gauge their attitudes toward the online competition and prior experience of online anatomical teaching/assessment. To evaluate performance, we compared scores of students who sat the online (2021) and in-person (2017) examinations, using 12 identical neuroradiology questions present in both years. Forty-six percent of NUNC 2021 participants had taken an online anatomy examination in the previous 12 months, but this did not impact examination performance significantly (p > 0.05). There was no significant difference in examination scores between in-person and online examinations using the 12 neuroradiology questions (p = 0.69). Fifty percent of participants found the online format less enjoyable, with 63% citing significantly fewer networking opportunities. The online competition was less stressful for 55% of participants. This study provides some evidence to suggest that student performance is not affected when undertaking online examinations and proposes that online neuroanatomy teaching methods, particularly for neuroradiology, may be equally as effective as in-person approaches within this context. Participants perceived online examinations as less stressful but raised concerns surrounding the networking potential and enjoyment of online events.

One-shot neuroanatomy segmentation through online data augmentation and confidence aware pseudo label.

Recently, deep learning-based brain segmentation methods have achieved great success. However, most approaches focus on supervised segmentation, which requires many high-quality labeled images. In this paper, we pay attention to one-shot segmentation, aiming to learn from one labeled image and a few unlabeled images. We propose an end-to-end unified network that joints deformation modeling and segmentation tasks. Our network consists of a shared encoder, a deformation modeling head, and a segmentation head. In the training phase, the atlas and unlabeled images are input to the encoder to get multi-scale features. The features are then fed to the multi-scale deformation modeling module to estimate the atlas-to-image deformation field. The deformation modeling module implements the estimation at the feature level in a coarse-to-fine manner. Then, we employ the field to generate the augmented image pair through online data augmentation. We do not apply any appearance transformations cause the shared encoder could capture appearance variations. Finally, we adopt supervised segmentation loss for the augmented image. Considering that the unlabeled images still contain rich information, we introduce confidence aware pseudo label for them to further boost the segmentation performance. We validate our network on three benchmark datasets. Experimental results demonstrate that our network significantly outperforms other deep single-atlas-based and traditional multi-atlas-based segmentation methods. Notably, the second dataset is collected from multi-center, and our network still achieves promising segmentation performance on both the seen and unseen test sets, revealing its robustness. The source code will be available at https://github.com/zhangliutong/brainseg.

The western giants of neuroanatomical past: an ode to yesterday - Part I.

"The only history is a mere question of one's struggle inside oneself. But that is the joy of it. One need neither discover Americas nor conquer nations, and yet one has as great a work as Columbus or Alexander to do," said David H. Lawrence. In this historical vignette, we look at the lives of certain western giants of neuroanatomy from the past. To understand the origin of today's advancements and successes in neurosurgery, a strong foothold on the path taken by anatomical greats is necessary. What curiosity inspired them to search the meaning of the human nervous system? Learning this from the paths of Herophilus, Galen, Franciscus Sylvius, Thomas Willis, Alexander Monro secundus, Luigi Rolando, François Magendie, and Martin Rathke, will propel us to create a better future for our successors.

The Historical Evolution of Topographical Mapping and Nomenclature of the Lateral Cervical and Lateral Spinal Nuclei.

The intricate organization of nuclei within the dorsolateral funiculus of the spinal cord has long been an area of interest in the field of neuroanatomy. Numerous researchers have endeavored to determine the morphology, neurochemistry, connections, and physiology of the lateral cervical nucleus and lateral spinal nucleus throughout history. This manuscript charts the historical progression in the mapping, naming, and comprehension of the lateral cervical nucleus and lateral spinal nucleus across a variety of species, such as rats, mice, marmosets, rhesus monkeys, and humans. It synthesizes significant research spanning decades, which together shed light on the nuanced topography of these nuclei, starting from Theodor Ziehen's foundational work in 1903, through Molander's precise mappings, to the detailed contemporary mappings by modern scholars. Despite the wealth of research elucidating the mappings of these nuclei, there remains a need for further investigation into their roles and neurochemical characteristics.

Unveiling the neuroanatomy of Josephoartigasia monesi and the evolution of encephalization in caviomorph rodents.

Caviomorph rodents are an exceptional model for studying the effects of ecological factors and size relations on brain evolution. These mammals are not only speciose and ecologically diverse but also present wide body size disparity, especially when considering their fossil relatives. Here, we described the brain anatomy of the largest known rodent, Josephoartigasia monesi, uncovering distinctive features within this species regarding other taxa. Albeit resembling extant pacarana Dinomys branickii, J. monesi stands out due to its longer olfactory tract and well-developed sagittal sinus. Challenging the previous hypothesis that giant rodents possessed comparatively smaller brains, we found that J. monesi and another giant extinct rodent, Neoepiblema acreensis, are within the encephalization range of extant caviomorphs. This was unraveled while developing the a Phylogenetic Encephalization Quotient (PEQ) for Caviomorpha. With PEQ, we were able to trace brain-size predictions more accurately, accounting for species-shared ancestry while adding the extinct taxa phenotypic diversity into the prediction model. According to our results, caviomorphs encephalization patterns are not the product of ecological adaptations, and brain allometry is highly conservative within the clade. We challenge future studies to investigate caviomorphs encephalization within different taxonomic ranks while increasing the sampled taxa diversity, especially of extinct forms, in order to fully comprehend the magnitude of this evolutionary stasis.

Decomposing cortical activity through neuronal tracing connectome-eigenmodes in marmosets.

Deciphering the complex relationship between neuroanatomical connections and functional activity in primate brains remains a daunting task, especially regarding the influence of monosynaptic connectivity on cortical activity. Here, we investigate the anatomical-functional relationship and decompose the neuronal-tracing connectome of marmoset brains into a series of eigenmodes using graph signal processing. These cellular connectome eigenmodes effectively constrain the cortical activity derived from resting-state functional MRI, and uncover a patterned cellular-functional decoupling. This pattern reveals a spatial gradient from coupled dorsal-posterior to decoupled ventral-anterior cortices, and recapitulates micro-structural profiles and macro-scale hierarchical cortical organization. Notably, these marmoset-derived eigenmodes may facilitate the inference of spontaneous cortical activity and functional connectivity of homologous areas in humans, highlighting the potential generalizing of the connectomic constraints across species. Collectively, our findings illuminate how neuronal-tracing connectome eigenmodes constrain cortical activity and improve our understanding of the brain's anatomical-functional relationship.

Functional neuroanatomy of basal forebrain projections to the basolateral amygdala: Transmitters, receptors, and neuronal subpopulations.

The projections of the basal forebrain (BF) to the hippocampus and neocortex have been extensively studied and shown to be important for higher cognitive functions, including attention, learning, and memory. Much less is known about the BF projections to the basolateral nuclear complex of the amygdala (BNC), although the cholinergic innervation of this region by the BF is actually far more robust than that of cortical areas. This review will focus on light and electron microscopic tract-tracing and immunohistochemical (IHC) studies, many of which were published in the last decade, that have analyzed the relationship of BF inputs and their receptors to specific neuronal subtypes in the BNC in order to better understand the anatomical substrates of BF-BNC circuitry. The results indicate that BF inputs to the BNC mainly target the basolateral nucleus of the BNC (BL) and arise from cholinergic, GABAergic, and perhaps glutamatergic BF neurons. Cholinergic inputs mainly target dendrites and spines of pyramidal neurons (PNs) that express muscarinic receptors (MRs). MRs are also expressed by cholinergic axons, as well as cortical and thalamic axons that synapse with PN dendrites and spines. BF GABAergic axons to the BL also express MRs and mainly target BL interneurons that contain parvalbumin. It is suggested that BF-BL circuitry could be very important for generating rhythmic oscillations known to be critical for emotional learning. BF cholinergic inputs to the BNC might also contribute to memory formation by activating M1 receptors located on PN dendritic shafts and spines that also express NMDA receptors.

Mode-based morphometry: A multiscale approach to mapping human neuroanatomy.

Voxel-based morphometry (VBM) and surface-based morphometry (SBM) are two widely used neuroimaging techniques for investigating brain anatomy. These techniques rely on statistical inferences at individual points (voxels or vertices), clusters of points, or a priori regions-of-interest. They are powerful tools for describing brain anatomy, but offer little insights into the generative processes that shape a particular set of findings. Moreover, they are restricted to a single spatial resolution scale, precluding the opportunity to distinguish anatomical variations that are expressed across multiple scales. Drawing on concepts from classical physics, here we develop an approach, called mode-based morphometry (MBM), that can describe any empirical map of anatomical variations in terms of the fundamental, resonant modes-eigenmodes-of brain anatomy, each tied to a specific spatial scale. Hence, MBM naturally yields a multiscale characterization of the empirical map, affording new opportunities for investigating the spatial frequency content of neuroanatomical variability. Using simulated and empirical data, we show that the validity and reliability of MBM are either comparable or superior to classical vertex-based SBM for capturing differences in cortical thickness maps between two experimental groups. Our approach thus offers a robust, accurate, and informative method for characterizing empirical maps of neuroanatomical variability that can be directly linked to a generative physical process.

The neuroanatomy of visual extinction following right hemisphere brain damage: Insights from multivariate and Bayesian lesion analyses in acute stroke.

Multi-target attention, that is, the ability to attend and respond to multiple visual targets presented simultaneously on the horizontal meridian across both visual fields, is essential for everyday real-world behaviour. Given the close link between the neuropsychological deficit of extinction and attentional limits in healthy subjects, investigating the anatomy that underlies extinction is uniquely capable of providing important insights concerning the anatomy critical for normal multi-target attention. Previous studies into the brain areas critical for multi-target attention and its failure in extinction patients have, however, produced heterogeneous results. In the current study, we used multivariate and Bayesian lesion analysis approaches to investigate the anatomical substrate of visual extinction in a large sample of 108 acute right hemisphere stroke patients. The use of acute stroke patient data and multivariate/Bayesian lesion analysis approaches allowed us to address limitations associated with previous studies and so obtain a more complete picture of the functional network associated with visual extinction. Our results demonstrate that the right temporo-parietal junction (TPJ) is critically associated with visual extinction. The Bayesian lesion analysis additionally implicated the right intraparietal sulcus (IPS), in line with the results of studies in neurologically healthy participants that highlighted the IPS as the area critical for multi-target attention. Our findings resolve the seemingly conflicting previous findings, and emphasise the urgent need for further research to clarify the precise cognitive role of the right TPJ in multi-target attention and its failure in extinction patients.

Fractals in Neuroanatomy and Basic Neurosciences: An Overview.

The introduction of fractal geometry to the neurosciences has been a major paradigm shift over the last decades as it has helped overcome approximations and limitations that occur when Euclidean and reductionist approaches are used to analyze neurons or the entire brain. Fractal geometry allows for quantitative analysis and description of the geometric complexity of the brain, from its single units to the neuronal networks.As illustrated in the second section of this book, fractal analysis provides a quantitative tool for the study of the morphology of brain cells (i.e., neurons and microglia) and its components (e.g., dendritic trees, synapses), as well as the brain structure itself (cortex, functional modules, neuronal networks). The self-similar logic which generates and shapes the different hierarchical systems of the brain and even some structures related to its "container," that is, the cranial sutures on the skull, is widely discussed in the following chapters, with a link between the applications of fractal analysis to the neuroanatomy and basic neurosciences to the clinical applications discussed in the third section.

The neuroanatomy of developmental language disorder: a systematic review and meta-analysis.

Developmental language disorder (DLD) is a common neurodevelopmental disorder with adverse impacts that continue into adulthood. However, its neural bases remain unclear. Here we address this gap by systematically identifying and quantitatively synthesizing neuroanatomical studies of DLD using co-localization likelihood estimation, a recently developed neuroanatomical meta-analytic technique. Analyses of structural brain data (22 peer-reviewed papers, 577 participants) revealed highly consistent anomalies only in the basal ganglia (100% of participant groups in which this structure was examined, weighted by group sample sizes; 99.8% permutation-based likelihood the anomaly clustering was not due to chance). These anomalies were localized specifically to the anterior neostriatum (again 100% weighted proportion and 99.8% likelihood). As expected given the task dependence of activation, functional neuroimaging data (11 peer-reviewed papers, 414 participants) yielded less consistency, though anomalies again occurred primarily in the basal ganglia (79.0% and 95.1%). Multiple sensitivity analyses indicated that the patterns were robust. The meta-analyses elucidate the neuroanatomical signature of DLD, and implicate the basal ganglia in particular. The findings support the procedural circuit deficit hypothesis of DLD, have basic research and translational implications for the disorder, and advance our understanding of the neuroanatomy of language.