65 research outputs found

    Common Fronto-temporal Effective Connectivity in Humans and Monkeys

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    Cognitive pathways supporting human language and declarative memory are thought to have uniquely evolutionarily differentiated in our species. However, cross-species comparisons are missing on site-specific effective connectivity between regions important for cognition. We harnessed a new approach using functional imaging to visualize the impact of direct electrical brain stimulation in human neurosurgery patients. Applying the same approach with macaque monkeys, we found remarkably comparable patterns of effective connectivity between auditory cortex and ventro-lateral prefrontal cortex (vlPFC) and parahippocampal cortex in both species. Moreover, in humans electrical tractography revealed rapid evoked potentials in vlPFC from stimulating auditory cortex and speech sounds drove vlPFC, consistent with prior evidence in monkeys of direct projections from auditory cortex to vocalization responsive regions in vlPFC. The results identify a common effective connectivity signature that from auditory cortex is equally direct to vlPFC and indirect to the hippocampus (via parahippocampal cortex) in human and nonhuman primates

    Common Fronto-temporal Effective Connectivity in Humans and Monkeys

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    Human brain pathways supporting language and declarative memory are thought to have differentiated substantially during evolution. However, cross-species comparisons are missing on site-specific effective connectivity between regions important for cognition. We harnessed functional imaging to visualize the effects of direct electrical brain stimulation in macaque monkeys and human neurosurgery patients. We discovered comparable effective connectivity between caudal auditory cortex and both ventro-lateral prefrontal cortex (VLPFC, including area 44) and parahippocampal cortex in both species. Human-specific differences were clearest in the form of stronger hemispheric lateralization effects. In humans, electrical tractography revealed remarkably rapid evoked potentials in VLPFC following auditory cortex stimulation and speech sounds drove VLPFC, consistent with prior evidence in monkeys of direct auditory cortex projections to homologous vocalization-responsive regions. The results identify a common effective connectivity signature in human and nonhuman primates, which from auditory cortex appears equally direct to VLPFC and indirect to the hippocampus

    The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe

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    The preponderance of matter over antimatter in the early Universe, the dynamics of the supernova bursts that produced the heavy elements necessary for life and whether protons eventually decay --- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our Universe, its current state and its eventual fate. The Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed plan for a world-class experiment dedicated to addressing these questions. LBNE is conceived around three central components: (1) a new, high-intensity neutrino source generated from a megawatt-class proton accelerator at Fermi National Accelerator Laboratory, (2) a near neutrino detector just downstream of the source, and (3) a massive liquid argon time-projection chamber deployed as a far detector deep underground at the Sanford Underground Research Facility. This facility, located at the site of the former Homestake Mine in Lead, South Dakota, is approximately 1,300 km from the neutrino source at Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino charge-parity symmetry violation and mass ordering effects. This ambitious yet cost-effective design incorporates scalability and flexibility and can accommodate a variety of upgrades and contributions. With its exceptional combination of experimental configuration, technical capabilities, and potential for transformative discoveries, LBNE promises to be a vital facility for the field of particle physics worldwide, providing physicists from around the globe with opportunities to collaborate in a twenty to thirty year program of exciting science. In this document we provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess.Comment: Major update of previous version. This is the reference document for LBNE science program and current status. Chapters 1, 3, and 9 provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess. 288 pages, 116 figure

    Human Auditory Cortical Activation during Self-Vocalization

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    During speaking, auditory feedback is used to adjust vocalizations. The brain systems mediating this integrative ability have been investigated using a wide range of experimental strategies. In this report we examined how vocalization alters speech-sound processing within auditory cortex by directly recording evoked responses to vocalizations and playback stimuli using intracranial electrodes implanted in neurosurgery patients. Several new findings resulted from these high-resolution invasive recordings in human subjects. Suppressive effects of vocalization were found to occur only within circumscribed areas of auditory cortex. In addition, at a smaller number of sites, the opposite pattern was seen; cortical responses were enhanced during vocalization. This increase in activity was reflected in high gamma power changes, but was not evident in the averaged evoked potential waveforms. These new findings support forward models for vocal control in which efference copies of premotor cortex activity modulate sub-regions of auditory cortex

    A2ML1 and otitis media : novel variants, differential expression, and relevant pathways

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    A genetic basis for otitis media is established, however, the role of rare variants in disease etiology is largely unknown. Previously a duplication variant within A2ML1 was identified as a significant risk factor for otitis media in an indigenous Filipino population and in US children. In this report exome and Sanger sequencing was performed using DNA samples from the indigenous Filipino population, Filipino cochlear implantees, US probands, Finnish, and Pakistani families with otitis media. Sixteen novel, damaging A2ML1 variants identified in otitis media patients were rare or low-frequency in population-matched controls. In the indigenous population, both gingivitis and A2ML1 variants including the known duplication variant and the novel splice variant c.4061 + 1 G>C were independently associated with otitis media. Sequencing of salivary RNA samples from indigenous Filipinos demonstrated lower A2ML1 expression according to the carriage of A2ML1 variants. Sequencing of additional salivary RNA samples from US patients with otitis media revealed differentially expressed genes that are highly correlated with A2ML1 expression levels. In particular, RND3 is upregulated in both A2ML1 variant carriers and high-A2ML1 expressors. These findings support a role for A2ML1 in keratinocyte differentiation within the middle ear as part of otitis media pathology and the potential application of ROCK inhibition in otitis media.Peer reviewe

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    New Developments in Understanding the Complexity of Human Speech Production

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    Speech is one of the most unique features of human communication. Our ability to articulate our thoughts by means of speech production depends critically on the integrity of the motor cortex. Long thought to be a low-order brain region, exciting work in the past years is overturning this notion. Here, we highlight some of major experimental advances in speech motor control research and discuss the emerging findings about the complexity of speech motocortical organization and its large-scale networks. This review summarizes the talks presented at a symposium at the Annual Meeting of the Society of Neuroscience; it does not represent a comprehensive review of contemporary literature in the broader field of speech motor control

    Metastatic Involvement of the Pituitary Gland: a systematic review with Pooled Individual Patient Data Analysis.

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    PURPOSE: To report a rare case of pituitary metastasis (PM) from hepatocellular carcinoma (HCC) and help better understand the incidence of PM and its most common presenting symptoms through a pooled individual patient data analysis. METHODS: Literature regarding PM was systematically reviewed with a pooled individual patient data analysis conducted. Pooled individual data analysis result is also compared with the result in a most recent systematic review. RESULTS: Our results demonstrate that the incidence of PM among all intracranial metastases is 0.87% (95% CI 0.56, 1.18); it is 1.9% (95% CI 1.46, 2.34) among all autopsied cancer cases; it is 11.56% (95% CI 7.08, 16.04) among all breast cancer patients who had hypophysectomies and 12.83% (95% CI 10.5, 15.16) among all autopsied breast cancer patients. The fixed effect model showed that the incidence of PM in breast cancer patients group is significantly higher (p \u3c 0.001) with an odds ratio of 6.71 (95% CI 4.24, 10.61). Breast and lung cancer are the most common primary cancer of PM with a percentage of 37.2 and 24.2 respectively. The next most common primary sites are prostate and kidney respectively, although the percentages for each are only about 5. Diabetes insipidus (DI) remains the most common symptom among all reported PM cases with a pooled incidence of 42.34% (95% CI 36.15, 48.53). Although not significant (χ(2) = 2.846, df = 1, p = 0.061), it is less common in the most recent reported cases which has a pooled incidence of 32.76% (95% CI 20.31, 45.21). DI is extremely rare in the reported PM cases from HCC (none of the eight cases presented with DI). The symptoms of anterior hypopituitarism (23.68 vs 39.66%, p = 0.015), visual deterioration (27.89 vs 41.38%, p = 0.039), cranial nerve palsies (21.58 vs 41.38%, p = 0.003) and headaches (15.79 vs 32.76%, p = 0.005) were reported significantly higher than previously described in the literature. CONCLUSIONS: Pituitary metastasis is rare in patients with cancer, and the pituitary gland is an uncommonly involved location in patients with intracranial metastases. With advanced diagnostic imaging techniques and increased awareness about the manifestation of sellar lesions, the incidence of cranial nerve palsies and anterior pituitarism are higher than reported. This information may allow earlier diagnosis of PM

    Hypertensive posterior reversible encephalopathy syndrome causing posterior fossa edema and hydrocephalus.

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    Posterior reversible encephalopathy syndrome (PRES) is a well characterized entity resulting from the inability of cerebral autoregulation to adequately protect the brain from uncontrolled hypertension. It primarily affects the occipital lobes, but can also involve the structures in the posterior fossa including the brainstem and cerebellum. Treatment usually consists of strict blood pressure control, but more aggressive management may be indicated with acutely worsening neurological status. We present a patient with hypertensive encephalopathy that resulted in hydrocephalus and brainstem compression necessitating surgical decompression requiring ventriculostomy and suboccipital craniectomy. In rare cases, PRES can present with severe brainstem compression requiring emergent posterior fossa decompression. When brainstem signs are present on exam, emergent posterior fossa decompression may be safer than ventriculostomy alone
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