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Sir Henry Dale was a renowned medical scientist known for his discoveries in physiology and pharmacology. Born in London in 1875, Dale attended Tollington Park College and later won a scholarship to Trinity College. He made significant contributions to the field of physiology, including the isolation of acetylcholine and the identification of chemical transmission of nerve impulses. Dale held various leadership roles and received numerous honors throughout his career. He passed away in 1968. [Extracted from the article]

The ratio of T1-weighted/T2-weighted magnetic resonance images (T1w/T2w MRI) has been successfully applied at the cortical level since 2011 and is now one of the most used myelin mapping methods. However, no reports have explored the histological validity of T1w/T2w myelin mapping in white matter. Here we compare T1w/T2w with ex vivo postmortem histology and in vivo MRI methods, namely quantitative susceptibility mapping (QSM) and multi-echo T2 myelin water fraction (MWF) mapping techniques. We report a discrepancy between T1w/T2w myelin maps of the human corpus callosum and the histology and analyse the putative causes behind such discrepancy. T1w/T2w does not positively correlate with Luxol Fast Blue (LFB)-Optical Density but shows a weak to moderate, yet significant, negative correlation. On the contrary, MWF is strongly and positively correlated with LFB, whereas T1w/T2w and MWF maps are weakly negatively correlated. The discrepancy between T1w/T2w MRI maps, MWF and histological myelin maps suggests caution in using T1w/T2w as a white matter mapping method at the callosal level. While T1w/T2w imaging may correlate with myelin content at the cortical level, it is not a specific method to map myelin density in white matter. [ABSTRACT FROM AUTHOR]

The COVID-19 global pandemic has forced the higher education sector to transition to an uncharted remote-learning format. This offers an opportunity to adopt active learning, which increases students' performance compared to lectures, narrows achievement gaps for underrepresented students, and promotes equity and inclusivity, as the basis of STEM education. [ABSTRACT FROM AUTHOR]

Nowadays, the "flipped classroom" approach is taking the center stage within medical education. However, very few reports on the implementation of the flipped classroom in neurology have been published to date, and this educational model still represents a challenge for students and educators alike. In this article, neurology educators from the American Academy of Neurology's A. B. Baker Section on Neurological Education analyze reports of flipped classroom in other medical/surgical subspecialties, review the current implementation in neurology, and discuss future strategies to flip the neurology curriculum through contextualization of the benefits and the consequences. ANN NEUROL 2020;87:4–9 [ABSTRACT FROM AUTHOR]

Throughout her career, Ungerleider explored the functional organization of the visual cortex in humans and non-human primates with neuroanatomical, neurophysiological, neuroimaging and behavioural methods [[2], [7]]. She was approached by Mortimer Mishkin, a scientific adversary of Pribram, as they had distinct views on the role of "pre-striate cortex [...] of the inferior temporal cortex" and "their contributions to perception" [[1]]. Together they published her first I Science i paper entitled 'A behavioral measure of homosynaptic and heterosynaptic temporal summation in the self-stimulation system of rats' in 1970, the same year she earned her Ph.D. Graph: Fig. [Extracted from the article]

Sperry and his PhD student Ronald Myers assessed visual deficits following the resection of the corpus callosum in cats [[7]]. Roger Wolcott Sperry made titanic contributions to neurobiology [[1]]. He won an Amos C. Miller Scholarship to join Oberlin College, where a Sperry Neuroscience Wing in the Kettering Hall building was inaugurated in 1990. [Extracted from the article]

David Hunter Hubel was one of the most outstanding neuroscientists of the twentieth century (Fig. References 1 David H Hubel - Biographical. Hubel married Ruth Izzard, a graduate of Donald Hebb's psychology department [[2]], and was ready to start a new job as an assistant resident in neurology at Johns Hopkins. [Extracted from the article]

Neuroimaging techniques, such as positron emission tomography and functional magnetic resonance imaging are essential tools for the analysis of organized neural systems in working and resting states, both in physiological and pathological conditions. They provide evidence of coupled metabolic and cerebral local blood flow changes that strictly depend upon cellular activity. In 1890, Charles Smart Roy and Charles Scott Sherrington suggested a link between brain circulation and metabolism. In the same year William James, in his introduction of the concept of brain blood flow variations during mental activities, briefly reported the studies of the Italian physiologist Angelo Mosso, a multifaceted researcher interested in the human circulatory system. James focused on Mosso's recordings of brain pulsations in patients with skull breaches, and in the process only briefly referred to another invention of Mosso's, the 'human circulation balance', which could non-invasively measure the redistribution of blood during emotional and intellectual activity. However, the details and precise workings of this instrument and the experiments Mosso performed with it have remained largely unknown. Having found Mosso's original manuscripts in the archives, we remind the scientific community of his experiments with the 'human circulation balance' and of his establishment of the conceptual basis of non-invasive functional neuroimaging techniques. Mosso unearthed and investigated several critical variables that are still relevant in modern neuroimaging such as the 'signal-to-noise ratio', the appropriate choice of the experimental paradigm and the need for the simultaneous recording of differing physiological parameters. [ABSTRACT FROM AUTHOR]

In the 1880s, the Italian physiologist Angelo Mosso claimed to have invented a ‘human circulation balance’ that measured the redistribution of blood during intellectual activity. Sandrone et al. have now unearthed Mosso’s original manuscripts in a rediscovery that tilts the balance of the history of neuroimaging.Neuroimaging techniques, such as positron emission tomography and functional magnetic resonance imaging are essential tools for the analysis of organized neural systems in working and resting states, both in physiological and pathological conditions. They provide evidence of coupled metabolic and cerebral local blood flow changes that strictly depend upon cellular activity. In 1890, Charles Smart Roy and Charles Scott Sherrington suggested a link between brain circulation and metabolism. In the same year William James, in his introduction of the concept of brain blood flow variations during mental activities, briefly reported the studies of the Italian physiologist Angelo Mosso, a multifaceted researcher interested in the human circulatory system. James focused on Mosso’s recordings of brain pulsations in patients with skull breaches, and in the process only briefly referred to another invention of Mosso’s, the ‘human circulation balance’, which could non-invasively measure the redistribution of blood during emotional and intellectual activity. However, the details and precise workings of this instrument and the experiments Mosso performed with it have remained largely unknown. Having found Mosso’s original manuscripts in the archives, we remind the scientific community of his experiments with the ‘human circulation balance’ and of his establishment of the conceptual basis of non-invasive functional neuroimaging techniques. Mosso unearthed and investigated several critical variables that are still relevant in modern neuroimaging such as the ‘signal-to-noise ratio’, the appropriate choice of the experimental paradigm and the need for the simultaneous recording of differing physiological parameters. [ABSTRACT FROM AUTHOR]

Decision making is a crucial part of our life: we sense information from the environment and perform our motor response. However, "whether" and "when" decisions are embodied still needs to be fully elucidated. Neuroimaging data obtained by the disentanglement of perceptual decision from motor preparation revealed an increase in connectivity between inferior frontal cortex and sensory regions, and the important role played by intraparietal sulcus in motor decisions. The results obtained as well as the new research questions prompted by this work are carefully discussed herein. [ABSTRACT FROM AUTHOR]

The article focuses on the injury caused to brain due to cognitive tasks. It is stated that Angelo Mosso, Italian physiologist has carried an experiment in which he hypothesized that cerebral blood flow increases with the cognitive work. It is further stated that the techniques like magnetic resonance imaging and positron emission tomography helps in studying pathological and physiological condition and enables the quantification and imaging of neural system in resting and working states.

Nowadays, the "flipped classroom" approach is taking the center stage within medical education. However, very few reports on the implementation of the flipped classroom in neurology have been published to date, and this educational model still represents a challenge for students and educators alike. In this article, neurology educators from the American Academy of Neurology's A. B. Baker Section on Neurological Education analyze reports of flipped classroom in other medical/surgical subspecialties, review the current implementation in neurology, and discuss future strategies to flip the neurology curriculum through contextualization of the benefits and the consequences. ANN NEUROL 2020;87:4-9. [ABSTRACT FROM AUTHOR]

The article offers information on Macdonald Critchley who was appointed as Goulstonian Lecture of the Fellows at the Royal College of Physicians. It mentions that Macdonald Critchley qualified with first class honors at the age of twenty one and remained as a house physician at his medical school in Bristol. It states that Macdonald Critchley followed in the footsteps of the great clinicians from Victorian and Edwardian ages.

The article offers information on neurologist Ugo Cerletti and his contribution to the field of neurology. Topics discussed include the development of electroconvulsive therapy (ECT) by Cerletti in the 1930s; his description of congenital syphilis and study of the effect of pituitary gland on skeletal development; and his work in the field of psychiatric illness.

An interview with neurophysiologist Torsten Wiesel is presented. On being asked about his relationship with neurophysiologist David Hubel, he comments on the rapport he shares with him. He discusses about mechanisms of hearing and voice recognition. He shares tips on scientific research for young scientists.

The article presents a biography of Robert Bartholow, a pioneer in the study of the effects of electrical current stimulation to the cortex in conscious human beings. He was born on November 28, 1931 in New Windsor, Maryland to Jeremiah and Pleasant Bartholow. Also discussed are his educational background, his stint as a medical staff in the U.S. Army, and his contributions to neurology.

The article features Italian neurophysiologist Giuseppe Moruzzi and his major achievements. It discusses his personal and academic background, his work as professor of physiology at various Italian universities in the 1940s, and his role as Head of the Institute of Human Physiology in Pisa in 1949. His research concerning conditioned reflexes and the neural mechanisms underlying the sleep-waking cycle, the awards and honorary degrees he received, and his death in March 1986 are also cited.

A biography of David Ferrier, a psychologist and neurologist, is presented. It offers information on his birth date and birthplace, his educational and career background, and his awards. Topics of his medical research works include brain stimulation, motor and sensory functions, cerebral physiology and pathology.

A biography of Italian anatomist Bartolomeo Panizza is presented. It offers information on his birth date and birthplace, and his educational and career background. Topics of his medical research works include pathways and cortical localizations of the visual system and anatomo-physiology of cranial nerves.

A biography of Sir Francis Martin Rouse Walshe, one of the pioneers in neurology, is presented. Walshe was born in London, England on September 19, 1885. He graduated from Church school, Prior Park College, and the University College School in London. Topics discussed include his achievements as a physician and neurologist, and information on papers and books that he has written.

The article presents an obituary for neurologist Dr. Norman Gerschwind.

An obituary for the neurologist Rita Levi-Montalcini is presented.

An obituary for an Italian physiologist Angelo Mosso is presented.

Poor outcomes after traumatic brain injury (TBI) are common yet remain difficult to predict. Diffuse axonal injury is important for outcomes, but its assessment remains limited in the clinical setting. Currently, axonal injury is diagnosed based on clinical presentation, visible damage to the white matter or via surrogate markers of axonal injury such as microbleeds. These do not accurately quantify axonal injury leading to misdiagnosis in a proportion of patients. Diffusion tensor imaging provides a quantitative measure of axonal injury in vivo, with fractional anisotropy often used as a proxy for white matter damage. Diffusion imaging has been widely used in TBI but is not routinely applied clinically. This is in part because robust analysis methods to diagnose axonal injury at the individual level have not yet been developed. Here, we present a pipeline for diffusion imaging analysis designed to accurately assess the presence of axonal injury in large white matter tracts in individuals. Average fractional anisotropy is calculated from tracts selected on the basis of high test-retest reliability, good anatomical coverage and their association to cognitive and clinical impairments after TBI. We test our pipeline for common methodological issues such as the impact of varying control sample sizes, focal lesions and age-related changes to demonstrate high specificity, sensitivity and test-retest reliability. We assess 92 patients with moderate-severe TBI in the chronic phase (≥6 months post-injury), 25 patients in the subacute phase (10 days to 6 weeks post-injury) with 6-month follow-up and a large control cohort (n = 103). Evidence of axonal injury is identified in 52% of chronic and 28% of subacute patients. Those classified with axonal injury had significantly poorer cognitive and functional outcomes than those without, a difference not seen for focal lesions or microbleeds. Almost a third of patients with unremarkable standard MRIs had evidence of axonal injury, whilst 40% of patients with visible microbleeds had no diffusion evidence of axonal injury. More diffusion abnormality was seen with greater time since injury, across individuals at various chronic injury times and within individuals between subacute and 6-month scans. We provide evidence that this pipeline can be used to diagnose axonal injury in individual patients at subacute and chronic time points, and that diffusion MRI provides a sensitive and complementary measure when compared to susceptibility weighted imaging, which measures diffuse vascular injury. Guidelines for the implementation of this pipeline in a clinical setting are discussed. [ABSTRACT FROM AUTHOR]

Abstract Diverse cortical networks and striatal brain regions are implicated in instruction-based learning (IBL); however, their distinct contributions remain unclear. We use a modified fMRI paradigm to test two hypotheses regarding the brain mechanisms that underlie IBL. One hypothesis proposes that anterior caudate and frontoparietal regions transiently co-activate when new rules are being bound in working memory. The other proposes that they mediate the application of the rules at different stages of the consolidation process. In accordance with the former hypothesis, we report strong activation peaks within and increased connectivity between anterior caudate and frontoparietal regions when rule-instruction slides are presented. However, similar effects occur throughout a broader set of cortical and sub-cortical regions, indicating a metabolically costly reconfiguration of the global brain state. The distinct functional roles of cingulo-opercular, frontoparietal and default-mode networks are apparent from their activation throughout, early and late in the practice phase respectively. Furthermore, there is tentative evidence of a peak in anterior caudate activity mid-way through the practice stage. These results demonstrate how performance of the same simple task involves a steadily shifting balance of brain systems as learning progresses. They also highlight the importance of distinguishing between regional specialisation and global dynamics when studying the network mechanisms that underlie cognition and learning. Highlights • We examine regional brain activity at different stages of instruction based learning. • Widespread transient activity occurs in the brain when new rules are presented. • This is consistent with a metabolically costly reconfiguration of the global brain state. • Frontoparietal & default-mode networks activate early vs late in the practice phase. • A small peak in anterior-caudate activity occurs midway through the practice phase. [ABSTRACT FROM AUTHOR]

Ischemic stroke is the leading cause of disability, but effective therapies are currently widely lacking. Recovery from stroke is very much dependent on the possibility to develop treatments able to both halt the neurodegenerative process as well as to foster adaptive tissue plasticity. Here we show that ischemic mice treated with neural precursor cell (NPC) transplantation had on neurophysiological analysis, early after treatment, reduced presynaptic release of glutamate within the ipsilesional corticospinal tract (CST), and an enhancedNMDAmediated excitatory transmission in the contralesional CST. Concurrently, NPC-treated mice displayed a reduced CST degeneration, increased axonal rewiring, and augmented dendritic arborization, resulting in long-term functional amelioration persisting up to 60 d after ischemia. The enhanced functional and structural plasticity relied on the capacity of transplanted NPCs to localize in the periischemic and ischemic area, to promote the upregulation of the glial glutamate transporter 1 (GLT-1) on astrocytes and to reduce peri-ischemic extracellular glutamate. The upregulation of GLT-1 induced by transplanted NPCs was found to rely on the secretion of VEGF by NPCs. Blocking VEGF during the first week after stroke reduced GLT-1 upregulation as well as long-term behavioral recovery in NPC-treated mice. Our results show that NPC transplantation, by modulating the excitatory-inhibitory balance and stroke microenvironment, is a promising therapy to ameliorate disability, to promote tissue recovery and plasticity processes after stroke. [ABSTRACT FROM AUTHOR]

It has been postulated that autism spectrum disorder is underpinned by an 'atypical connectivity' involving higher-order association brain regions. To test this hypothesis in a large cohort of adults with autism spectrum disorder we compared the white matter networks of 61 adult males with autism spectrum disorder and 61 neurotypical controls, using two complementary approaches to diffusion tensor magnetic resonance imaging. First, we applied tract-based spatial statistics, a 'whole brain' non-hypothesis driven method, to identify differences in white matter networks in adults with autism spectrum disorder. Following this we used a tract-specific analysis, based on tractography, to carry out a more detailed analysis of individual tracts identified by tract-based spatial statistics. Finally, within the autism spectrum disorder group, we studied the relationship between diffusion measures and autistic symptom severity. Tract-based spatial statistics revealed that autism spectrum disorder was associated with significantly reduced fractional anisotropy in regions that included frontal lobe pathways. Tractography analysis of these specific pathways showed increased mean and perpendicular diffusivity, and reduced number of streamlines in the anterior and long segments of the arcuate fasciculus, cingulum and uncinate--predominantly in the left hemisphere. Abnormalities were also evident in the anterior portions of the corpus callosum connecting left and right frontal lobes. The degree of microstructural alteration of the arcuate and uncinate fasciculi was associated with severity of symptoms in language and social reciprocity in childhood. Our results indicated that autism spectrum disorder is a developmental condition associated with abnormal connectivity of the frontal lobes. Furthermore our findings showed that male adults with autism spectrum disorder have regional differences in brain anatomy, which correlate with specific aspects of autistic symptoms. Overall these results suggest that autism spectrum disorder is a condition linked to aberrant developmental trajectories of the frontal networks that persist in adult life. [ABSTRACT FROM AUTHOR]

Neural oscillations and their association with brain states and cognitive functions have been object of extensive investigation over the last decades. Several electroencephalography (EEG) and magnetoencephalography (MEG) analysis approaches have been explored and oscillatory properties have been identified, in parallel with the technical and computational advancement. This review provides an up-to-date account of how EEG/MEG oscillations have contributed to the understanding of cognition. Methodological challenges, recent developments and translational potential, along with future research avenues, are discussed. [ABSTRACT FROM AUTHOR]

This study aimed to investigate if two weeks of working memory (WM) training on a progressive N-back task can generate changes in the activity of the underlying WM neural network. Forty-six healthy volunteers (23 training and 23 controls) were asked to perform the N-back task during three fMRI scanning sessions: (1) before training, (2) after the half of training sessions, and (3) at the end. Between the scanning sessions, the experimental group underwent a 10-session training of working memory with the use of an adaptive version of the N-back task, while the control group did not train anything. The N-back task in the scanning sessions was relatively easy (n = 2) in order to ensure high accuracy and a lack of between-group differences at the behavioral level. Such training-induced differences in neural efficiency were expected. Behavioral analyses revealed improved performance of both groups on the N-back task. However, these improvements resulted from the test-retest effect, not the training outside scanner. Performance on the non-trained stop-signal task did not demonstrate any transfer effect. Imaging analysis showed changes in activation in several significant clusters, with overlapping regions of interest in the frontal and parietal lobes. However, patterns of between-session changes of activation did not show any effect of training. The only finding that can be linked with training consists in strengthening the correlation between task performance accuracy and activation of the parietal regions of the neural network subserving working memory (left superior parietal lobule and right supramarginal gyrus posterior). These results suggest that the effects of WM training consist in learning that, in order to ensure high accuracy in the criterion task, activation of the parietal regions implicated in working memory updating must rise. [ABSTRACT FROM AUTHOR]