Decreased glomerular filtration rate (GFR) and albuminuria may be accompanied by brain pathology. Here we investigated whether changes in these kidney measures are linked to development of new MRI-detected infarcts and microbleeds, and progression of white matter hyperintensity volume. The study included 2671 participants from the population-based AGES-Reykjavik Study (mean age 75, 58.7% women). GFR was estimated from serum creatinine, and albuminuria was assessed by urinary albumin-to-creatinine ratio. Brain MRI was acquired at baseline (2002-2006) and 5 years later (2007-2011). New MRI-detected infarcts and microbleeds were counted on the follow-up scans. White matter hyperintensity progression was estimated as percent change in white matter hyperintensity volumes between the two exams. Participants with a large eGFR decline (over 3 ml/min/1.73m2 per year) had more incident subcortical infarcts (odds ratio 1.53; 95% confidence interval 1.05, 2.22), and more marked progression of white matter ...
The Framingham Offspring Cohort were recruited in 1971 and consisted of 5124 children and spouses of children of the original Framingham Cohort.28 Offspring subjects have been examined 7 times since 1971, and between 1999 and 2001, they were invited to undergo a brain MRI using a standard protocol. For the current analysis, only subjects attending examination 5 were included, and risk factor data from this examination were related to findings from brain MRI examinations. Data from examination 5 were used because a larger number of subjects had risk factor and MRI data available than from exam 6 or 7. Subjects were excluded from MRI examination if they had metal in the eyes or central nervous system, claustrophobia, valvular prosthesis, cardiac pacemaker, vascular clip, cochlear implant or other implantable device, or if they refused.. Of those offspring who attended examination 5, 3562 were alive as of September 2001, the cutoff for the analysis. Of them, 1939 had an MRI examination of the brain ...
PURPOSE OF REVIEW: There has been a rapid increase in studies using diffusion-weighted magnetic resonance imaging (DWI) to interrogate white matter structure in the human brain. This review considers the evidence that interindividual variation in white matter structure is behaviourally relevant. RECENT FINDINGS: Maturation or deterioration of white matter throughout the lifespan relates to development or decline in specific cognitive skills. In addition, age-independent relationships between white matter anatomy and ability are found in healthy adult populations. Such relationships may in part be determined by genetics but can also be driven by experience. SUMMARY: Individual differences in white matter anatomy, visible using DWI, have consequences for behaviour. The discovery of such relationships highlights the potential for identification of imaging biomarkers that could predict how well patients will respond to specific interventions.
S. Mori, S. Wakana, L.M. Nagae-Poetscher, and P.C.M. van Zijl. Amsterdam: Elsevier; 2005, 284 pages, $195.. Diffusion tensor imaging (DTI) is becoming increasingly available on clinical scanners, thus providing neuroradiologists and other investigators with the ability to assess and quantify white matter abnormalities in ways that were impossible with conventional MR imaging methods. DTI is an MR imaging technique that is sensitive to the diffusion of water in anisotropic tissue and is thus ideal for the imaging and characterization of white matter fiber bundles. Because of the complexity of white matter anatomy, the localization of tracts is difficult without a good understanding of their 3D relationships. This volume provides annotated 3D and cross-sectional maps derived from DTI data and is intended to enable the interpretation of the complex 3D white matter anatomy visualized with DTI and the identification of specific white matter tracts.. Chapter 1 includes a brief introduction to the ...
In this cohort of community-dwelling older adults, greater arterial stiffness was associated with greater volume of WMH localized within the left superior longitudinal fasciculus as measured 10 years later. Our results suggest selective spatial vulnerability of the white matter to long-term cerebrovascular consequences of central arterial stiffness in aging.. Our study extends previous cross-sectional findings in racially homogeneous cohorts of adults ranging in age from late 50s to mid-70s in 2 ways.13-17 First, we examined longitudinal associations in a racially diverse cohort of older adults living in the community, and second, we examined the spatial distribution of objective measures of white matter abnormalities, including hyperintensities and FA. Most neuroimaging studies have relied on semiquantitative ratings of hyperintensities combined across 2 large brain areas: periventricular and deep. Among the reports of a spatial distribution of brain abnormalities in relationship with arterial ...
NOS1-ex1f VNTR is associated with WM microstructure in females in a large sample of participants with ADHD and healthy controls. Whether this association is part of a neurodevelopmental pathway from NOS1 to ADHD symptoms should be further investigated in future studies.
Clinical Trials - clinicaltrials.gov Animal studies have shown that thyroid hormone can improve white matter integrity after damage to myelin, which insulates a...
Functional brain images are extraordinarily rich data sets that reveal distributed brain networks engaged in a wide variety of cognitive operations. It is a substantial challenge both to create models of cognition that mimic behavior and underlying cognitive processes and to choose a suitable analytic method to identify underlying brain networks.. Most of the contemporary techniques used in analyses of functional neuroimaging data are based on univariate approaches in which single image elements (i.e. voxels) are considered to be computationally independent measures. Beyond univariate methods (e.g. statistical parametric mapping), multivariate approaches, which identify a network across all regions of the brain rather than a tessellation of regions, are potentially well suited for analyses of brain imaging data. A multivariate method (e.g. partial least squares) is a computational strategy that determines time-varying distributed patterns of the brain (as a function of a cognitive task). ...
Read about a study suggesting that analysis of white matter hyperintensity (a measure of the risk of stroke) may serve as a biomarker for SCD children.
TY - JOUR. T1 - A cyclooxygenase-2 inhibitor attenuates white matter damage in chronic cerebral ischemia. AU - Wakita, Hideaki. AU - Tomimoto, Hidekazu. AU - Akiguchi, Ichiro. AU - Lin, Jin Xi. AU - Miyamoto, Katsuichi. AU - Oka, Nobuyuki. PY - 1999/5/14. Y1 - 1999/5/14. N2 - The effects of nimesulide, a cyclooxygenase-2 inhibitor, were examined during chronic cerebral hypoperfusion. After bilateral ligation of the common carotid arteries in 30 rats, 21 received dosages of 2 or 5mg/kg nimesulide daily and nine received vehicle daily for 14 days. The serum was then analyzed biochemically, and pathological changes were estimated in the white matter by the emergence of major histocompatibility complex (MHC) antigen- immunoreactive activated microglia and white matter lesions. In the vehicle- treated animals, activated microglia and white matter lesions were observed. Following treatment with either 2 or 5mg/kg nimesulide, the magnitude of these changes was reduced (p , 0.001) without significant ...
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Transmission Electron Micrograph (TEM) of nerve; section of Schwann cell and myelinated axon. Myelin sheath in blue. Magnification: 45,000X; 9 x 7 print. - Stock Image C022/0085
In a major study that uses cutting-edge imaging, researchers show that people with depression have alterations in the white matter part of the brain.
Neurological function in patients with slowly growing brain tumors can be preserved even after extensive tumor resection. However, the global process of cortical reshaping and cerebral redistribution cannot be understood without taking into account the white matter tracts. The aim of this study was to predict the functional consequences of tumor-induced white matter damage by computer simulation. A computational model was proposed, incorporating two cortical patches and the white matter connections of the uncinate fasciculus. Tumor-induced structural changes were modeled such that different aspects of the connectivity were altered, mimicking the biological heterogeneity of gliomas. The network performance was quantified by comparing memory pattern recall and the plastic compensatory capacity of the network was analyzed. The model predicts an optimal level of synaptic conductance boost that compensates for tumor-induced connectivity loss. Tumor density appears to change the optimal plasticity ...
see equation (2.2)), that is elastin volume fraction VE, collagen volume fraction VC, radius rF of collagen fibres, density Λc of intermolecular cross-links, and the inverse of standard deviation measure μ−1F of collagen fibres orientation distribution. Mechanical problem M for obtaining arterial current (loaded) configuration (Pi: luminal pressure; ri (re): internal (external) radius; r: radial coordinate) from the (stress-free) reference configuration (α: opening angle; ri,o (re,o): internal (external) radius; ro: radial coordinate). Stages S0, S1, S2 and S3 of the addressed physiopathological mechanism. TGF-β, transforming growth factor beta; MMPs, matrix metalloproteinases; IL, interleukin; SMC, smooth muscle cell. For model details, readers can refer to §5. ...
Here is an interesting article in the LA Times that doesnt actually mention MS, let alone CCSVI, but it does mention cortisone, myelin, brain white matter, and oligodendrocytes: Basically the article seems to be saying (toward the end of the ...
The fundamental basis of axonal ensheathment in any species is to faithfully transmit neuronal signals along the nerve fibers and optimize desired cellular responses. To maximize the speed of conduction and/or to minimize the loss of nerve signals, many species evolved mechanisms in which axonal lengths remained short (as seen in insects) by increasing the diameter of the axons or by clustering voltage-gated Na+ channels to discrete unmyelinated regions of the axon, the node of Ranvier, as seen in myelinated nerve fibers of vertebrates. Most invertebrate species use some type of glial cells to ensheath their axons without generating a myelin sheath. The insulation is contiguous without any breaks, suggesting that primitive nodal structures or clustering of voltage-gated Na+ channels may not exist in invertebrates ...
I am trying to develop a simple axon model that represents nodes of Ranvier connected by "perfectly insulating" myelinated internodal segments. Sweeney channel mechanics are used at the nodes (sodium and leakage currents). I would like to apply stimulation to this model using the extracellular mechanism, with the extracellular potentials at the nodes of Ranvier calculated through interpolation within a FEM program (ANSYS Ansoft). Since the internodal myelinated segments are perfectly insulating, I did not add any channel mechanics or transmembrane capacitance to these segments, nor did I apply a non-zero extracellular voltage. My procedure code for creating such an axon is below ...
A team has found that external stimulation has an impact on the postnatal development of a specific region of the brain. The team is from the Childrens National Medical Center.
Health,...MIT team says cognition suffers as nervous system network decays with ...THURSDAY Jan. 15 (HealthDay News) -- The white matter that connects... By comparing brain scans of groups of healthy young and old adults M... White matter is made up of the neuronal axons that connect neurons in...,Memory,Loss,Tied,to,Brains,White,Matter,medicine,medical news today,latest medical news,medical newsletters,current medical news,latest medicine news
Colour enhanced Transmission Electron Micrograph (TEM) showing myelinated axon of a nerve cell in section. Magnification unknown. - Stock Image C017/5995
The traditional description of MS emphasizes the notion that this disease is an inflammatory and demyelinating condition of the white matter of the CNS. Consistent with this, a large number of MR imaging studies have been devoted to the detection, description, and quantification of white matter abnormalities of the brain and spinal cord of patients with MS (16). The increased use of MR imaging in the assessment of MS has, however, disclosed that the extent of white matter abnormalities measured using conventional MR imaging contributes only partially to the clinical manifestations of the disease, including the accumulation of irreversible disability. One of the main reasons for this discrepancy is likely to be the inability of conventional MR imaging to detect subtle structural changes (including axonal loss) known to occur in the so-called normal appearing tissue of the brain of patients with MS (1-4, 17, 18). In this context, several studies have shown that quantitative MR imaging technology ...
This unique volume is a comprehensive, well-illustrated study of the organization of the white matter pathways of the brain. Schmahmann and Pandya have analyzed and synthesized the corticocortical and corticosubcortical connections of the major areas of the cerebral cortex of the rhesus monkey. The result is a detailed understanding of the constituents of the cerebral white matter and the organization of the fiber tracts.
UCL Discovery is UCLs open access repository, showcasing and providing access to UCL research outputs from all UCL disciplines.
Nonspecific white matter changes is a condition in which white tissues in the brain change for some unknown reason. Though there...
White matter is brain tissue that is located below the surface gray matter. It is composed of nerve fibers that connect the different areas of the brain.
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ObjectiveTo examine the association between a Mediterranean-style diet (MeDi) and brain magnetic resonance imaging white matter hyperintensity volume (WMHV).Des
TY - JOUR. T1 - Peripheral nerve injury triggers central sprouting of myelinated afferents. AU - Woolf, Clifford J.. AU - Shortland, Peter. AU - Coggeshall, Richard E.. PY - 1992/1/2. Y1 - 1992/1/2. N2 - THE central terminals of primary afferent neurons are topographically highly ordered in the spinal cord1. Peripheral receptor sensitivity is reflected by dorsal horn laminar location: low-threshold mechanoreceptors terminate in laminae III and IV (refs 2, 3) and high-threshold nociceptors in laminae I, II and V (refs 4, 5). Unmyelinated C fibres, most of which are nociceptors6, terminate predominantly in lamina II (refs 5, 7). There is therefore an anatomical framework for the transfer of specific inputs to localized subsets of dorsal horn neurons. This specificity must contribute to the relationship between a low-intensity stimulus and an innocuous sensation and a noxious stimulus and pain. We now show that after peripheral nerve injury the central terminals of axotomized myelinated afferents, ...
View Stock Photo of Human Skin Crosssection Showing The Epidermis Dermis Perichondrium Elastic Cartilage A Myelinated Nerve Fiber And A Muscular Artery. Find premium, high-resolution photos at Getty Images.
Looking for online definition of dorsal longitudinal fasciculus in the Medical Dictionary? dorsal longitudinal fasciculus explanation free. What is dorsal longitudinal fasciculus? Meaning of dorsal longitudinal fasciculus medical term. What does dorsal longitudinal fasciculus mean?
Myelinated fibers and axons distribution in phrenic nerve of male and female wistar- kyoto (WKY) and spontaneously hypertensive rats (SHR). Anaceres Ribeiro Rodrigues1, Renata da Silva Ferreira1, Helio Cesar Salgado2, Carlos Augusto Carvalho de Vasconcelos3, Valéria Paula Sassoli Fazan1* Abstract. Histological examination of the diaphragm showed gender differences in fiber composition but gender differences on phrenic nerve myelinated fiber morphometry were not thoroughly addressed. A descriptive morphologic and morphometric study of the phrenic nerves in male and female SHR and WKY was recently published but the myelinated fiber morphometry needs further exploration. After arterial pressure and heart rate recordings, phrenic nerves of young adult (20 week-old) male and female SHR and WKY were prepared for epoxy resin embedding and light microscopy. Morphometric analysis was performed with the aid of computer software, with special attention to myelinated fiber and their respective axons area ...
To better understand why this finding is important, you need to know the players. Subclinical cerebrovascular disease is defined as the presence of silent brain infarcts and white matter hyperintensities. Research has shown that individuals with greater white matter hyperintensity volume and evidence of subclinical infarcts are at greater risk of experiencing an ischemic stroke (especially cryptogenic stroke) or dying. (2). An ischemic stroke, also known as a cerebral infarction, is caused by a blockage in a blood vessel in the brain. Ischemic stroke is the most common type of stroke. Of the more than 795,000 people in the United States who have a stroke every year, about 87 percent of them are ischemic stroke.(3) Silent brain infarcts are strokes that are void of clinically overt stroke-like symptoms. However, they are associated with subtle cognitive and physical deficits that often are not noticed. According to a study reported in Stroke, about 20 percent of stroke-free older adults have ...
To assess whether there was a relationship between these functional interactions and white matter microstructure across participants, we used tract-based spatial statistics (TBSS) to investigate local correlations between FA and ppTMS/spTMS MEP ratio effect size (16). We used MEP ratios with 6- and 12-ms IPLs from right hand response trials in the pre-SMA/M1 IPL experiment and the rIFG/M1 IPL experiment. Therefore, we had four different and uncorrelated regressors in the TBSS multiple regression analysis. Effects were reported as being significant at a one-tailed statistical threshold of P , 0.001 (uncorrected) and a cluster size of ,10 voxels (16). We found 2 clusters significantly correlated with the TMS effect in the pre-SMA/M1 experiment at an IPL of 6 ms. These clusters lay in dorsal white matter likely to connect pre-SMA, premotor, motor, and parietal areas. At an IPL of 12 ms, we found 6 clusters significantly correlated with pre-SMA/M1 interactions. Again, some of these clusters lay in ...
TY - JOUR. T1 - Relative conduction velocities of small myelinated and non-myelinated fibres in the central nervous system.. AU - Waxman, S. G.. AU - Bennett, Michael V. L.. PY - 1972/8/16. Y1 - 1972/8/16. UR - http://www.scopus.com/inward/record.url?scp=0015512637&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=0015512637&partnerID=8YFLogxK. M3 - Article. C2 - 4506206. AN - SCOPUS:0015512637. VL - 238. SP - 217. EP - 219. JO - Nature. JF - Nature. SN - 0028-0836. IS - 85. ER - ...
PubMed Central Canada (PMC Canada) provides free access to a stable and permanent online digital archive of full-text, peer-reviewed health and life sciences research publications. It builds on PubMed Central (PMC), the U.S. National Institutes of Health (NIH) free digital archive of biomedical and life sciences journal literature and is a member of the broader PMC International (PMCI) network of e-repositories.
Regression of myelinated peripheral nerve fibers in the lower extremities contributes to sarcopenia and balance dysfunction in normal aging. This subclinical regression of myelinated fibers (MFs) is heavily influenced by alterations in microvasculature, though the mechanism underlying these age-related degenerative phenomena remains unclear. The aim of the present study was to examine age-related regressions in myelinated distal peripheral nerve fibers as well as capillary architecture in rats using both morphological and histochemical methods. MFs were categorized into tertiles of large, medium, and small sizes based on the distribution of MF diameters. A two-way ANOVA was used to assess effects of fiber size (large/medium/small) and group (young/elderly) on myelin thickness, axon diameter, myelin perimeter, axon perimeter, and G-ratio (axon diameter/fiber diameter). Significant main effects were observed for both MF size and group with respect to all dimensions except for G-ratio. Values for
Background: Schizophrenia can be conceptualized as a form of dysconnectivity between brain regions. To investigate the neurobiological foundation of dysconnectivity, one approach is to analyze white matter structures, such as the pathology of fiber tracks. S100B is considered a marker protein for glial cells, in particular oligodendrocytes and astroglia, that passes the blood brain barrier and is detectable in peripheral blood. Earlier Studies have consistently reported increased S100B levels in schizophrenia. In this study, we aim to investigate associations between S100B and structural white matter abnormalities.Methods: We analyzed data of 17 unmedicated schizophrenic patients (first and recurrent episode) and 22 controls. We used voxel based morphometry (VBM) to detect group differences of white matter structures as obtained from T1-weighted MR-images and considered S100B serum levels as a regressor in an age-corrected interaction analysis. Results: S100B was increased in both patient subgroups.
New findings by Columbia researchers suggest that for the development of Alzheimers disease, along with amyloid deposits, white matter hyperintensities (WMHs) may be a second necessary factor.
The clinical evidences of variable epileptic propagation in occipital lobe epilepsy (OLE) have been demonstrated by several studies. However the exact localization of the epileptic focus sometimes represents a problem because of the rapid propagation to frontal, parietal, or temporal regions. Each white matter pathway close to the supposed initial focus can lead the propagation towards a specific direction, explaining the variable semiology of these rare epilepsy syndromes. Some new insights in occipital white matter anatomy are herein described by means of white matter dissection and compared to the classical epileptic patterns, mostly based on the central position of the primary visual cortex. The dissections showed a complex white matter architecture composed by vertical and longitudinal bundles, which are closely interconnected and segregated and are able to support specific high order functions with parallel bidirectional propagation of the electric signal. The same sublobar lesions may ...
Also called "brain rust," DeCarli says that when he began his research in 1990, "everyone thought these hyperintensities were just innocent changes associated with aging.". He has since focused his attention on an emerging connection between white matter and neurological maladies and their less-mysterious counterparts in other parts of the body: stroke, heart attack, diabetes, hypertension and atherosclerosis.. Stroke and white matter hyperintensities, for instance, share the same risk factors, DeCarli says. "Having these hyperintensities on your brain scan indicates that you are at risk for stroke.". Referring to it as "the million-dollar question of my research," DeCarli has sought links between Alzheimers disease and white matter hyperintensities.. "We found that hyperintensities injure the frontal lobes of the brain and impair the brains ability to manipulate and store information," he explains. DeCarlis research team also discovered that white matter hyperintensity-causing vascular ...
Critical white matter structures in the brains of babies who are born so prematurely that they weigh less than 1,500 grams develop more robustly when their mothers breast-feed them, compared with preemie peers who are fed formula.
The results remained the same regardless of a persons age, gender, ethnic group, education, and if they had a gene thought to be a strong risk factor for dementia, called the ApoEe4 gene.. "The most interesting finding in this study was that white matter hyperintensities, or ministrokes, predicted memory problems, while strokes predicted non-memory problems," said study author Jose Luchsinger, MD, MPH, with Columbia University Medical Center in New York.. "Traditionally, ministrokes and strokes are thought to have a common origin and to more strongly predict non-memory cognitive problems. There are an increasing number of studies challenging the idea that all white matter hyperintensities are similar to strokes. The fact that white matter hyperintensities more strongly predicted memory problems could challenge traditional views that white matter hyperintensities are milder versions of stroke that are produced only by conditions such as high blood pressure," said Luchsinger. Luchsinger says more ...
PubMedID: 26541556 | The cross-sectional and longitudinal relationships between white matter hyperintensities and dementia in patients with Parkinsons disease: A retrospective analysis of 132 patients in a single center. | Archives of gerontology and geriatrics | 11/28/2015
Following on from research showing that long-term meditation is associated with gray matter increases across the brain, an imaging study involving 27 long-term meditators (average age 52) and 27 controls (matched by age and sex) has revealed pronounced differences in white-matter connectivity between their brains.. The differences reflect white-matter tracts in the meditators brains being more numerous, more dense, more myelinated, or more coherent in orientation (unfortunately the technology does not yet allow us to disentangle these) - thus, better able to quickly relay electrical signals.. While the differences were evident among major pathways throughout the brain, the greatest differences were seen within the temporal part of the superior longitudinal fasciculus (bundles of neurons connecting the front and the back of the cerebrum) in the left hemisphere; the corticospinal tract (a collection of axons that travel between the cerebral cortex of the brain and the spinal cord), and the ...
Following on from research showing that long-term meditation is associated with gray matter increases across the brain, an imaging study involving 27 long-term meditators (average age 52) and 27 controls (matched by age and sex) has revealed pronounced differences in white-matter connectivity between their brains.. The differences reflect white-matter tracts in the meditators brains being more numerous, more dense, more myelinated, or more coherent in orientation (unfortunately the technology does not yet allow us to disentangle these) - thus, better able to quickly relay electrical signals.. While the differences were evident among major pathways throughout the brain, the greatest differences were seen within the temporal part of the superior longitudinal fasciculus (bundles of neurons connecting the front and the back of the cerebrum) in the left hemisphere; the corticospinal tract (a collection of axons that travel between the cerebral cortex of the brain and the spinal cord), and the ...
TY - JOUR. T1 - Cognitive function and white matter changes associated with renal transplantation. AU - Gupta, Aditi. AU - Lepping, Rebecca J.. AU - Yu, Alan S.L.. AU - Perea, Rodrigo D.. AU - Honea, Robyn A.. AU - Johnson, David K. AU - Brooks, William M.. AU - Burns, Jeffrey M.. PY - 2016/3/1. Y1 - 2016/3/1. N2 - Background: End-stage renal disease (ESRD) is a disease with an aging population and a high prevalence of cognitive impairment affecting quality of life, health care costs and mortality. Structural changes in the brain with decreased white matter integrity have been observed in ESRD. Understanding the changes in cognition and associated changes in brain structure after renal transplantation can help define the mechanisms underlying cognitive impairment in ESRD. Methods: We conducted a prospective, observational cohort study in ESRD patients listed for renal transplantation and followed them post-transplantation. We assessed their cognitive function with a battery of neuropsychological ...
Evidence-Based Complementary and Alternative Medicine (eCAM) is an international peer-reviewed, Open Access journal that seeks to understand the sources and to encourage rigorous research in this new, yet ancient world of complementary and alternative medicine.
Polydisperse fiber networks are the basis of many natural and manufactured structures, ranging from high-performance biobased materials to components of living cells and tissues. The formation and behavior of such networks are given by fiber properties such as length and stiffness as well as the number density and fiber-fiber interactions. Studies of fiber network behavior, such as connectivity or rigidity thresholds, typically assume monodisperse fiber lengths and isotropic fiber orientation distributions, specifically for nano scale fibers, where the methods providing time-resolved measurements are limited. Using birefringence measurements in a microfluidic flow-focusing channel combined with a flow stop procedure, we here propose a methodology allowing investigations of length-dependent rotational dynamics of nanoscale polydisperse fiber suspensions, including the effects of initial nonisotropic orientation distributions. Transition from rotational mobility to rigidity at entanglement ...
Honor Whiteman/ Medical News Today) - Scientists may have advanced our understanding of the brain mechanisms behind Alzheimers disease, after uncovering a process that precedes the buildup of toxic proteins that is a hallmark of the condition.. In a mouse study, scientists at the University of Southern California (USC) in Los Angeles reveal how damage to cells called pericytes can trigger white matter disease, which is associated with dementia.. Also, the study findings suggest that these brain changes may occur as early as the age of 40.. White matter disease is characterized by the degeneration of white matter. This is the brain tissue that contains nerve fibers, the thread-like structures that carry signals from the nerve cells, or neurons, to other areas of the body.. In white matter disease, these nerve fibers become damaged, and this causes problems with memory, thinking, and balance. (…). read full story ...