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What Does White Matter In The Brain Do

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Wanted: A Behavioral Neurology Of White Matter

What Is White Matter and Why Does It Matter? – Science Ambassador Scholarship

The study of higher functions in humans requires consideration of all the brains neural tissues. Long neglected as a contributor to the organization of cognitive and emotional operations, white matter is the object of intense, intriguing, and increasingly fruitful efforts to improve our understanding. Studying people with white matter disorders to correlate their brain lesions with specic behavior changes promises a wealth of insights. Increasingly, this method will be complemented by sophisticated neuroimaging techniques that yield detailed visualization of white matter tracts as they participate in the cognitive and emotional operations of distributed neural networks.

In practical terms, an appreciation of the brain-behavioral importance of white matter disorders can greatly benet patients, especially as early recognition and treatment often determine an outcome. In theoretical terms, further study of white matter and its disorders expands our knowledge of the brain as an extraordinarily complex structure in which the connectivity provided by white matter is central to cognition, emotion, and consciousness itself.

Comparison Of Microglia Activation Upon Systemic Inflammation And Load

To evaluate the neuroinflammation status in aging and AD, we first investigated brain sections from people who died of acute inflammatory diseases, which were used as positive controls for the further study. In addition, we compared a young non-demented control group and a group of LOAD tissue samples . For each group, we compared the expression of IBA1, HLA-DR, and CD68 between the patients who died of acute inflammatory disease and those who died without systemic inflammation . In the non-demented group, white-matter microglia of samples with acute infection showed deramified morphology and expressed significantly higher levels of IBA1 and CD68. However, the expression of HLA-DR did not change significantly in the white matter between acute-inflammation- and non-inflammation groups . In the LOAD group, the expression of IBA1, HLA-DR, and CD68 was not significantly different between inflammation- and non-inflammation groups . In conclusion, these data indicate that acute inflammation in addition to neurodegeneration did not further alter microglial morphology.

White Matter Consists Mainly Of Nerve Fibers

White matter appears white because the protective wrapping around nerve fibers, or axons, is a pale, fatty tissue called myelin.

Axons are like the electric wires of the brain,” says;Rhonda Voskuhl, MD, professor of neurology at the UCLA Brain Research Institute and director of the UCLA Multiple Sclerosis Program in Los Angeles.

In MS, the immune system attacks the myelin in the brain, spinal cord, and optic nerves. The attack causes inflammation that eventually leads to sclerosis, which is the medical term for scarring.

“When MS attacks these parts of the brain, it’s like stripping the rubber off the wires. That slows down conduction speed and causes the types of MS symptoms that come and go, says Dr. Voskuhl. An attack may last for weeks or months, but then the inflammation cools off, and the area recovers completely or partially.

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Why The White Brain Matters

If you set out to understand a buildings lighting system but examined only the xtures, switches, and outlets, never the wiring in the walls and basement, you might be pretty puzzled. Something like that has happened in the study of the brain, suggests behavioral neurologist Christopher Filley. Scientists now beginning to probe the long-neglected half of the brain called the white matter arediscovering how it specializes in connectivity, with bundles of insulated wiring that link neurons within and between gray matter areas into ensembles that may produce the light of conscious mental functioning. A pioneer of research on white matter, Filley proposes a new eld of study that would bring the other half of the brain into the mainstream of neuroscience.

Acute Isolation Of Microglia From Adult Mouse Brain

White matter fibres of the human brain

Animals were sacrificed by means of saline perfusion under inhalation anesthesia with 4% isoflurane in oxygen. The brains were isolated and kept in ice-cold dissection solution . For the isolation of microglia from white and gray matter regions, the forebrain and cerebellum were cut into approximately 1.5 mm thick coronal sections. Dissection was performed under magnifying glass with the tissue wet with medium A. Corpus callosum, cerebellar white matter were pooled from 2 to 3 animals of a particular age group and considered as one sample from that age group. From the collected tissue, microglia were isolated at high purity using a discontinuous Percoll gradient . All steps of the isolation and staining procedure were performed at 4°C. Briefly, the tissue was transferred to a tissue homogenizer , and mechanically dissociated. The brain homogenate was then filtered through a 70 m cell strainer, washed with medium A, and pelleted by centrifugation . The density gradient separation was done using Percoll solutions with different densities . To obtain a stock isotonic Percoll solution , nine volume parts of Percoll were mixed with one volume part of 10x HBSS. Percoll solutions with the appropriate concentration were prepared via dilution of 100% Percoll with 1x PBS.

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What Increases White Matter

Researchers have also demonstrated that using our brains in a specific way can change the structure of white matter. For instance, one experiment found that regularly practicing a musical instrument increases the level of organization within white matter in the areas important for musical performance.

The Clinical Importance Of White Matter Hyperintensities On Brain Magnetic Resonance Imaging: Systematic Review And Meta

  • Stéphanie Debette, neurologist and research fellow123,
  • H S Markus, professor of neurology1
  • 1Clinical Neuroscience, St Georges University of London, London
  • 2Department of Neurology, Boston University School of Medicine, B601, 72 East Concord Street, Boston, MA 02118, USA
  • 3Department of Neurology, EA2691, Lille University Hospital, Lille, France
  • Correspondence to: S Debette sdebettebu.edu
    • Accepted 20 May 2010

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  • aInstituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, 21941-909, Brazil;
  • bDepartment of Psychology, Vanderbilt University, Nashville, TN 37203;
  • cInstituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, 21941-901, Brazil;
  • dDepartment of Psychology, University of Sheffield, Reading RG6 6AH, United Kingdom;
  • eDepartment of Psychiatry and Behavioral Sciences, University of California, Davis, CA 95616;
  • fDepartment of Psychology, University of Richmond, Richmond, VA 23173;
  • gCenter for Zoo and Wild Animal Health, Copenhagen Zoo, 2000 Copenhagen, Denmark;
  • hSchool of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Braamfontein 2000, Johannesburg, South Africa;
  • iDepartment of Anthropology, The George Washington University, Washington, DC 20052;
  • jCenter for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052;
  • kDepartment of Biological Sciences, Vanderbilt University, Nashville, TN 37212;
  • lVanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232
  • See allHide authors and affiliations

      White Matter And Cognition: Making The Connection

      Grey and White Matter of the Brain â Spinal Cord | Lecturio

      Behavioral Neurology Section, Departments of Neurology and Psychiatry, University of Colorado School of Medicine, Aurora, Colorado;

      Denver Department of Veterans Affairs Medical Center, Denver, Colorado; and

      Address for reprint requests and other correspondence: C. M. Filley, Behavioral Neurology Section, 12631 East 17th Ave., B-185, Aurora, CO 80045 .

    • Email
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      White Matter In The Brain

      Think of the brain as a computer system, and it might be easier to understand. According to the UC Davis Health System, the gray matter of our brain is the computer and the white matter is the cables that connect everything together and transmit signals.

      Want more of a biological explanation? White matter is tissue in the brain composed of nerve fibers. The fibers connect nerve cells and are covered by myelin . The myelin is what gives white matter its white color.

      Myelin speeds up the signals between the cells, enabling the brain cells to quickly send and receive messages. It also provides insulation for the fibers, preventing the brain from short-circuiting.

      White matter makes up about half of the brain, with gray matter making up the other half.

      Key Takeaways: What Is White Matter

      • White matter of the brain is situated beneath the outer cortex layer, also known as gray matter. Most of the brain is composed of white matter.
      • White brain matter appears white because of myelin that is wrapped around the nerve axons of white matter. Myelin helps to facilitate nerve impulse transmission.
      • White matter nerve fibers connect the cerebrum with the spinal cord and other areas of the brain.
      • There are three main types of white matter nerve fiber tracts: commissural fibers, association fibers, and projection fibers.
      • Commissural fibers connect corresponding regions of the left and right hemispheres of the brain.
      • Association fibers connect brain regions within the same hemisphere.
      • Projection fibers connect the cerebral cortex to the brainstem and spinal cord.

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      Rna Amplification Microarray And Analysis

      Microglia were sorted as a CD11bhi/CD45int/DAPIneg population in RNA lysis buffer, and RNA was extracted using the Qiagen RNeasy micro kit . RNA concentration and integrity were measured on the Experion RNA HighSens chip . Additional RNA amplification was performed with the Nugen Ovation RNA amplification kit. Subsequently, RNA was labeled and hybridized onto the Illumina mouseref-8 V2.0 expression beadchip containing 25,600 probes, coding for 19,100 genes. Genomestudio was used to generate expression values. Raw data were preprocessed and analyzed using project R and BioConductor package Limma . Background correction was done using infrared negative probes, and subsequently, quantile normalization and log2 transformation were applied. Probes were filtered out below a detection level of p< 0.05 in all samples as no expression cases. A linear model approach was used to perform differential gene expression analysis . For further GO and pathway analysis, DAVID were used. Heatmaps were generated using the heatmap.2 function of Bioconductor Package gplots.

      Immunohistochemistry For Human Brain Tissues

      White matter fibres of the human brain

      Paraffin-embedded tissue of human brains from AD and control groups were immunostained with IBA1 , CD68 and HLA-DR . Paraffin-embedded tissues from different age groups were immunostained with CD68 and HLA-DR . Sections were deparaffinized with xylene and rehydrated gradually from 100% ethanol to demi water. For antigen retrieval, the sections were placed in 10 mM sodium citrate buffer in a microwave for 12 min.

      After rinsing in PBS, sections were pre-incubated in 3% H2O2 for 30 min and then blocked with 10% normal horse serum in PBS with 0.3% Triton-X100 for 30 min. Sections were incubated overnight at 4°C with abovementioned primary antibodies in PBS with 0.3% Triton-X100 and 1% normal horse serum. Sections were incubated with horse anti-mouse biotinylated antibody for 1 h at room temperature, incubated in avidin-biotin-peroxidase complex for 30 min, and then visualized with DAB. Sections were counterstained with Cresyl Violet and mounted with DePeX.

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      What Is The Function Of The White Matter Of The Spinal Cord

      White matters primary job is to coordinate and send brain signals from one region of the cerebrum to another, and also from the cerebrum to the spinal cord and other areas of the brain. A few generations ago, doctors thought that white matter was passive tissue that merely insulated and protected gray matter.

      What Does White Matter On The Brain Indicate

      White matter disease is a disease that affects the nerves that link various parts of the brain to each other and to the spinal cord. These nerves are also called white matter. White matter disease causes these areas to decline in their functionality. This disease is also referred to as leukoaraiosis.

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      What Is The Function Of White Matter

      What is the function of white matter? The white fatty myelin that gives this tissue its name is also essential to its function myelin insulates axons, letting the signal within travel far faster, enabling the nerve cell function that is essential to normal motor and sensory function.

      What is the function of the white matter of the brain?;In the most general sense, the gray matter of the brain facilitates information processing, and the white matter facilitates information transfer; both are critical for efcient operation of the neural networks responsible for a specic mental domain.

      What is the function of white matter quizlet?;White matter in brain is known as the cerebral white matter. The white matter deep to the cortical gray matter is responsible for communication between cerebral areas and between the cerebral cortex and lower CNS.

      What is the function of GREY and white matter?;The grey matter also extends from the brain into the spinal cord. The grey matter creates a hornlike structure throughout the inside of the spinal cord while the white matter makes up the surrounding sections of the spinal cord. The grey matter does extend to the spinal cord to make signaling more effective.

      Increased White Matter Inflammation In Aging

      White Matter Abnormalities, Neurodegeneration And Migraines
      • 1Department of Neuroscience, Section Medical Physiology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
      • 2Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
      • 3Department of Pathology, VU University Medical Center, Amsterdam, Netherlands
      • 4Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
      • 5Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Wilrijk, Belgium
      • 6Department of Neurology and Alzheimer Research Center, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
      • 7Biobank, Institute Born-Bunge, Wilrijk, Belgium
      • 8Department of Pathology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
      • 9Neuroimmunology Unit, Blizard Institute of Cell and Molecular Science, Barts and The London School of Medicine and Dentistry, London, United Kingdom

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      How Are White Matter Lesions Treated

      There is no specific treatment for white matter lesions. It is sensible to make sure that treatable conditions such as high blood pressure are recognised and treated in case the white matter lesions are due to this. It is sensible to make sure conditions such as diabetes mellitus and high cholesterol are under control. If you smoke, it is sensible to stop.

      Contact Professor Emsley;to learn how he can help you with the diagnosis and management of a wide variety of neurological conditions.

      Gray Matter Is Made Of Nerve Cell Bodies Or Neurons

      Gray matter, made up of the cells of the central nervous system called neurons, is thickly located in the outer areas of the brain, called the cortex. If you look at the outside of the brain, it looks gray.

      The white matter carries messages from point A to point B,” Stone says. “The gray matter is point A and point B.”

      As MS progresses, changes occur in the gray matter that are different from those occurring in the white matter.

      If you cut off the connections between nerve cells, they eventually die,” Voskuhl explains. “This causes a shrinking of brain tissue, called gray matter atrophy. MS causes inflammation in white matter and atrophy in gray matter. You can measure atrophy by actual loss of brain volume.”

      But demyelination and lesions can also happen in gray matter, even if this isnt visible using conventional magnetic resonance imaging scans, according to;Léorah Freeman, MD, PhD, a neurologist and assistant professor at Dell Medical School at the University of Texas at Austin.

      In fact, Dr. Freeman says, We know from postmortem studies that in the most severe cases, up to 70 percent of the gray matter can be demyelinated in people with MS.

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      White Matter Density Changes With Age

      Within the regions of interest derived from the FA analysis results, there were prominent white matter density increases with age in the internal capsule, in inter-thalamic pathways, and in the corpus callosum. Additional white matter density increases with age were observed in prefrontal regions, in the arcuate fasciculus, and in visual pathways .

      The Role Of White Matter In Distributed Neural Networks

      White matter fibres of the human brain

      In general, white matter can be seen as providing for the transfer of information within distributed neural networks, while gray matter subserves information processing . Accordingly, primary white matter damage results most prominently in cognitive slowing, whereas primary gray matter disease leads to more specific cognitive deficits, most apparent in the cortical dementia AD, which features amnesia, aphasia, apraxia, and amnesia related to regional neuronal and synaptic loss . However, as discussed below, suboptimal conduction velocity can also impair information processing; a good example of this phenomenon is optic nerve demyelination in acute optic neuritis that impairs visual acuity in multiple sclerosis . Neurons are the fundamental units of all networks, and distinctions between the operations of white and gray matter are not absolute. Disease may begin in the white matter or the gray, or progress from one tissue to the other, and complex interactions between the two are typical. As myelocentrism can be as limiting as corticocentrism, a balanced view of the representation of cognitive function is crucial. In this section, we consider physiological aspects of white matter underlying both information transfer and processing as a basis for appreciating the effects of myelin and axonal dysfunction.

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      Incident Dementia And Cognitive Decline

      White matter hyperintensities were associated with an increased risk of dementia in the general population, but not in studies on high risk populations . When subtypes of dementia were assessed, the three studies that investigated the relation of white matter hyperintensities with incident vascular dementia found a significant association, both in the general population and in patients with mild cognitive impairment.313341 Conversely, although the meta-analysis testing the relation of white matter hyperintensities with incident Alzheimers disease yielded an overall significant association, this association was driven by the large population based study,31 whereas the two smaller studies on patients with mild cognitive impairment did not identify any association.4149 Finally, our systematic review suggests that, in most studies looking at the association of white matter hyperintensities with decline in cognitive performance, white matter hyperintensities were associated with a faster decline in global cognitive performance as well as in executive function and processing speed. This was true both in the general population and in high risk patients with mild cognitive impairment, memory problem, or cerebrovascular disease.

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