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At least 793 records · Page 44Linked to original sources
PubMed2006

White-matter integrity predicts stroop performance in patients with geriatric depression.

BACKGROUND: This study tested the hypothesis that microstructural white matter abnormalities in frontostriatal-limbic tracts are associated with poor response inhibition on the Stroop task in depressed elders. METHOD: Fifty-one elders with major depression participated in a 12-week escitalopram trial. Diffusion tensor imaging was used to determine fractional anisotropy (FA) in white matter regions. Executive function (response inhibition) was assessed with the Stroop task. Voxelwise correlational analysis was used to examine the relationship between Stroop performance and fractional anisotropy. RESULTS: Significant associations between FA and Stroop color word interference were evident in multiple frontostriatal-limbic regions, including white matter lateral to the anterior and posterior cingulate cortex and white matter in prefrontal, insular, and parahippocampal regions. CONCLUSIONS: These findings suggest that microstructural white matter abnormalities of frontostriatal-limbic networks are associated with executive dysfunction of late-life depression. This observation provides the rationale for examination of specific frontostriatal-limbic pathways in the pathophysiology of geriatric depression.

Aged↗
PubMed2006

Reduced amygdala volumes in first-episode bipolar disorder and correlation with cerebral white matter.

BACKGROUND: Previous magnetic resonance imaging (MRI) findings on amygdala volume abnormalities in bipolar disorder have been inconsistent, which may partly reflect clinical heterogeneity. It is unclear whether amygdala abnormalities are present early in the course of illness and/or are the consequence of disease progression. METHODS: Twenty patients with first-episode bipolar disorder and 23 matched healthy comparison subjects were included. Magnetic resonance images were used to measure amygdala volumes, as well as whole brain measures of gray and white matter volume. RESULTS: First-episode bipolar patients had significant reductions in amygdala volume relative to healthy subjects in an analysis of covariance that accounted for the effects of age, sex, and whole brain volume. First-episode patients also showed a trend reduction in cerebral white matter volume, and there was a significant correlation between cerebral white matter volume and total amygdala volume in patients but not control subjects. CONCLUSIONS: These findings indicate that amygdala volume deficits are present early in the course of bipolar disorder and may occur within a neuroanatomical context of reduced cerebral white matter. Additional research should examine whether the nature of regional white matter deficits, particularly in frontal-temporal tracts, may help parse the pathophysiology of amygdala volume abnormalities in bipolar disorder.

Adult↗
PubMed2005

Characterisation of the organic matter pool in manures.

In this research, different types of animal manure were evaluated with respect to organic matter (OM), total organic carbon (C(ot)), total N (N(t)), C(ot)/N(t) ratio, water-soluble organic carbon (C(w)), organic N (N(org)), carbohydrates, C(w)/N(org) ratio, humic acid-like carbon (C(ha)), fulvic acid-like carbon (C(fa)), humification index ((C(ha)/C(ot))x100) (HI) and the C(ha)/C(fa) and NH(4)(+)-N/NO(3)(-)-N ratios. In comparison with the limits set by the Spanish legislation for organic fertilisers, most of the manures had high OM contents, moderate N(org) concentrations (except in the case of the chicken and pig manures where this parameter was high) and C(ot)/N(t) ratios above the value stated in the legislation. The study of the different fractions of organic matter showed that the horse, pig and rabbit manures had the greatest content of C(ot). However, the fraction of easily-biodegradable organic compounds (C(w)) was significantly higher in the horse, goat and chicken manures. The study also showed that, in most cases, the percentage of fulvic acid-like C was greater than that of the humic acid-like C, indicating that the organic matter of these wastes is not completely humified. Values of HI ((C(ha)/C(ot))x100) and C(ha)/C(fa) ratio in the studied manures were not significantly different. Regarding the parameters related to the organic matter stability such as C(w), carbohydrates and the C(ot)/N(t), C(w)/N(org) and NH(4)(+)-N/NO(3)(-)-N ratios, it has been determined that the organic matter of these materials was not completely stabilised. The heterogeneity in OM composition of the studied manures did not allow the formulation of simple equations for evaluation of the composition of these wastes from easily-determined parameters.

Animals↗
PubMed2006

Changes in the chemical characteristics of water-extractable organic matter during composting and their influence on compost stability and maturity.

Composting is the biochemical transformation of waste organic matter by microorganisms whose metabolism occurs in the water-soluble phase. Therefore, a study of the changes occurring in compost dissolved organic matter can be useful for assessing its stability and maturity. In light of the variety of parameters generally utilized to study composting processes, this work aims at identifying the major chemical processes that occur in solution and their influence on the attainment of stability and maturity with composting time. Compost stability, assessed by means of respirometric analysis which determined oxygen demand as a result of mineralization of the compost's organic matter, and compost maturity evaluated with Lepidium sativum L. seed bioassays, were found to be highly related to the nature and content of water-soluble organic matter. Moreover, fractionation of the water-extractable organic carbon showed that the ratio of hydrophobic to hydrophilic carbon increased to values greater than unity for stabilized compost. These results together with the analysis for non-cellulosic polysaccharides, phenolic compounds and organic nitrogen within the water extracts, confirmed the influence of solubilization, mineralization and organic matter transformation on the quality of the final compost.

Biodegradation, Environmental↗
PubMed2006

Evolution of soil organic matter changes using pyrolysis and metabolic indices: a comparison between organic and mineral fertilization.

The aim of this study was to evaluate chemical and biochemical changes of organic matter in fertilized (ammonium nitrate) and amended (vermicompost and manure) soils using pyrolysis and metabolic indices. The metabolic potential [dehydrogenase (DH-ase)/water soluble organic carbon (WSOC)], the metabolic quotient (qCO2) and the microbial quotient (Cmic:Corg) were calculated as indices of soil organic matter evolution. Pyrolysis-gas chromatography (Py-GC) was used to study structural changes in the organic matter. Carbon forms and microbial biomass have been measured by dichromate oxidation and fumigation-extraction methods, respectively. Dehydrogenase activity has been tested using INT (p-Iodonitrotetrazolium violet) as substrate. The results showed that organic amendment increased soil microbial biomass and its activity which were strictly related to pyrolytic mineralization and humification indices (N/O, B/E3). Mineral fertilization caused a greater alteration of native soil organic matter than the organic amendments, in that a high release of WSOC and relatively large amounts of aliphatic pyrolytic products, were observed. Therefore, the pyrolysis and metabolic indices provided similar and complementary information on soil organic matter changes after mineral and organic fertilization.

Biomass↗
PubMed2006

MR spectroscopy and diffusion tensor imaging of the brain in congenital muscular dystrophy with merosin deficiency: metabolite level decreases, fractional anisotropy decreases, and apparent diffusion coefficient increases in the white matter.

Brain magnetic resonance spectroscopy (MRS) and diffusion tensor imaging (DTI) in one patient with merosin-deficient congenital muscular dystrophy (MDCMD) revealed significant metabolite (choline, creatine, N-acetyl aspartate) level reductions, fractional anisotropy (FA) reduction and increased apparent diffusion coefficient (ADC) in the white matter (p<0.01, all). In the gray matter, the MRS properties did not differ significantly from those in controls. The ADC and FA, however, differed significantly as in the white matter, although the differences were less pronounced. This is the first quantitative MR study of the brain in a patient with MDCMD, which revealed that the concentrations of all MRS measured metabolites were decreased only in the white matter. This observation, combined with the DTI observed ADC increases and FA decrease, indicated a presence of vasogenic edema in the white matter.

Anisotropy↗
PubMed2004

alpha-Phenyl-n-tert-butyl-nitrone attenuates hypoxic-ischemic white matter injury in the neonatal rat brain.

White matter of the neonatal brain is highly sensitive to hypoxic-ischemic insult. The susceptibility of premature oligodendrocytes (OLs) to free radicals (FRs) produced during hypoxia-ischemia (HI) has been proposed as one of the mechanisms involved. To test this hypothesis, and to further investigate if the FR scavenger alpha-phenyl-N-tert-butyl-nitrone (PBN) attenuates hypoxic-ischemic white matter damage (WMD), postnatal day 4 (P4) SD rats were subjected to bilateral common carotid artery ligation (BCAL), followed by 8% oxygen exposure for 20 min. Pathological changes were evaluated on P6 and P9, 2 and 5 days after the HI insult. HI caused severe WMD including rarefaction, necrosis and cavity formation in the corpus callosum, external and internal capsule areas. OL injury was evidenced by degeneration of O4 positive OLs on P6. Disrupted myelination was verified by decreased immunostaining of myelin basic protein (MBP) on P9. Axonal injury was demonstrated by increased amyloid precursor protein (APP) immunostaining on both P6 and P9. Two lipid peroxidation end products, malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), showed a one-fold elevation within 1-24 h following HI. 4-HNE immunostaining was found to specifically localize in the white matter area. Furthermore, pyknotic O4+ OLs were double-labeled with 4-HNE. These findings suggest that FRs are involved in the pathogenesis of neonatal WMD. PBN (100 mg/kg, i.p.) treatment alleviated the pathological changes of WMD following HI. It improved the survival of O4 positive OLs, attenuated hypomyelination and reduced axonal damage. PBN treatment also decreased the brain concentration of MDA/4-HNE and positive 4-HNE staining in the white matter area. These findings indicate that in the current WMD model, PBN protects both OLs and axons, the two main components in the white matter, from neonatal HI insult. FR scavenging appears to be the primary mechanism underlying its neuroprotective effect.

Age Factors↗
PubMed2004

Absence of localized grey matter volume changes in the motor cortex following spinal cord injury.

The consequences of spinal cord injury (SCI) have considerable effects on motor function, typically resulting in functional impairment. Pathological changes have been studied at the site of trauma, rostrocaudally within the cord, and in the periphery. Few studies, however, have investigated the consequences of SCI at the cortical level. Magnetic resonance imaging (MRI) was used to explore the morphological changes in the grey and white matter within the primary motor (M1) cortex of individuals with cervical SCI. The "precentral knob," a landmark of M1 cortex dedicated to hand function, was selected for regionally specific measurements of change. Thirty-one hemispheres of SCI subjects and 28 hemispheres of control subjects were compared using a manual measurement after the images were segmented into grey matter, white matter, and cerebral spinal fluid (CSF). No significant differences in grey matter area measured at the precentral knob were found with the manual approach. An automated voxel-based morphometric analysis was also performed and demonstrated no significant differences in grey or white matter volume within an M1 region of interest. These data suggest that there is no gross anatomical change within M1 following cervical SCI. Our previously reported findings of reorganization of cortical motor output maps following SCI therefore likely result from changes in functional organization rather than anatomical changes.

Adolescent↗
PubMed2006

Neuroprotection by cilostazol, a phosphodiesterase type 3 inhibitor, against apoptotic white matter changes in rat after chronic cerebral hypoperfusion.

In the present study, we elucidated effect of cilostazol to prevent the occurrence of vacuolation and rarefaction of the white matter in association with apoptosis induced by bilateral occlusion of common carotid arteries in the male Wistar rats. Rats orally received vehicle (DMSO) or 60 mg kg(-1) day(-1) (orally) cilostazol for 3, 7, 14 or 30 days. In the vehicle group, increased vacuolation and rarefactions in the white matter were accompanied by extensive activation of both microglial and astroglial cells with suppression of oligodendrocytes in association with increased TNF-alpha production, caspase-3 immunoreactivity and TUNEL-positive cells in the white matter including optic tract. Post-treatment with cilostazol (60 mg kg(-1) day(-1)) strongly suppressed not only elevated activation of astroglia and microglia but also diminished oligodendrocytes following chronic cerebral hypoperfusion. In conclusion, cilostazol (60 mg kg(-1) day(-1), orally) significantly reduced the apoptotic cell death in association with decreased TNF-alpha production and caspase-3-positive cells in the white matter of rat brains subjected to bilateral occlusion of common carotid arteries, consequently ameliorating vacuoles and rarefaction changes in the white matter.

Administration, Oral↗
PubMed2006

Carbon and nitrogen composition and stable isotope as potential indicators of source and fate of organic matter in the salt marsh of the Changjiang Estuary, China.

Elemental (TOC, TN, C/N) and stable carbon and nitrogen isotopic (delta(13)C, delta(15)N) compositions were measured for surface sediments, three sediment vibrocores, plants, and suspended particulate matter (SPM) collected from salt marsh of the Changjiang Estuary. The purpose of this study is to characterize the sources of organic matter in sediments and to further elucidate the factors influencing the isotope signature in the salt marsh. Our results indicate that organic matter preserved in the sediments is predominantly controlled by the particulate organic matter in the Changjiang Estuary. The in situ contribution of marsh plants carbon to sediment organic matter is clearest in the high marsh, where the low delta(13)C of the plants (-28.1 per thousand) is reflected by a sediment delta(13)C (-24.7 per thousand) lower than values found for the low marsh and bare flat sediments (-23.4 per thousand and -23.0 per thousand, respectively). The effect of grain size on the spatial difference of isotope composition in the marsh sediments is insignificant, based on the observation that similar isotope values are found in different size particles, both for delta(13)C and delta(15)N. Nutrient utilization by plant assimilation, however, shows great impact on the surface sediment delta(15)N composition, due to the isotope fractionation. With extensive plant coverage and the consequent low surface water nitrate concentration, delta(15)N values of the high marsh surface sediments show (15)N enrichment.

Carbon↗
PubMed2006

Systemic endotoxin administration results in increased S100B protein blood levels and periventricular brain white matter injury in the preterm fetal sheep.

OBJECTIVE: Intrauterine infection is suggested to cause perinatal brain white matter injury. The aim of the present study was to clarify, whether intravenous application of endotoxin results in neuropathological findings and increased blood levels of the S100B protein, which is a consolidated marker of brain injury. METHODS: Twenty-one fetal sheep were chronically catheterized at a mean gestational age of 107+/-1 days (0.7 of gestation). Three days after surgery fetuses received either 100 (n = 9), 500 (n = 5) or 2500 ng (n = 1) lipopolysaccharide (LPS; E. coli; O127:B8, Sigma-Aldrich) or 2 ml 0.9% saline (n = 6) i.v. S100B protein blood levels were assessed before during and after LPS or placebo administration. Brain damage was evaluated by light microscopy. Selected areas of the periventricular white matter were also examined by electron microscopy. RESULTS: Histopathological screening revealed no evidence for cortical neuronal cell damage in both groups. However, LPS treatment resulted in inflammatory infiltrates in all animals and cystic lesions in the periventricular brain white matter in two fetuses. On electron micrographs, infiltrate forming cells appeared to be activated microglia. S100B protein blood levels were significantly higher in the LPS group at 1h (p < 0.01) after LPS injection, peaking at 3h (p < 0.001) and returning to baseline between 12 and 72 h. CONCLUSION: Intravenous application of endotoxin caused focal periventricular brain white matter injury, inflammation and an increase in S100B protein release. It is suggested that longitudinal investigations of S100B protein blood levels offer a tool for the early detection of white matter injury.

Animals↗
PubMed2006

Global expression of NGF promotes sympathetic axonal growth in CNS white matter but does not alter its parallel orientation.

Axonal regeneration is normally limited after injuries to CNS white matter. Infusion of neurotrophins has been successful in promoting regenerative growth through injured white matter but this growth generally fails to extend beyond the infusion site. These observations are consistent with a chemotropic effect of these factors on axonal growth and support the prevailing view that neurotrophin-induced axonal regeneration requires the use of gradients, i.e., gradually increasing neurotrophin levels along the target fiber tract. To examine the potential of global overexpression of neurotrophins to promote, and/or modify the orientation of, regenerative axonal growth within white matter, we grafted nerve growth factor (NGF) responsive neurons into the corpus callosum of transgenic mice overexpressing NGF throughout the CNS under control of the promoter for glial fibrillary acidic protein. One week later, glial fibrillary acidic protein and chondroitin sulfate proteoglycan immunoreactivity increased within injured white matter around the grafts. NGF levels were significantly higher in the brains of transgenic compared with non-transgenic mice and further elevated within injury sites compared with the homotypic region of the non-injured side. Although there was minimal outgrowth from neurons grafted into non-transgenic mice, extensive parallel axonal regeneration had occurred within the corpus callosum up to 1.5 mm beyond the astrogliotic scar (the site of maximum NGF expression) in transgenic mice. These results demonstrate that global overexpression of neurotrophins does not override the constraints limiting regenerative growth to parallel orientations and suggest that such factors need not be presented as positive gradients to promote axonal regeneration within white matter.

Animals↗
PubMed2006

Heavy neurofilament accumulation and alpha-spectrin degradation accompany cerebellar white matter functional deficits following forebrain fluid percussion injury.

Evidence for diffuse traumatic axonal injury (TAI) in clinical cases and animal models of traumatic brain injury (TBI) indicate that pathophysiological mechanisms extend to regions remote from the injury epicenter. The potential for indirect cerebellar trauma contributing to TBI pathophysiology is of significance since impairment of motor function and coordination is a common consequence of TBI but is also a domain associated with cerebellar function. The relationship between cerebellar white matter structure and function following traumatic head injury has not been examined. Using the fluid percussion injury (FPI) device applied unilaterally in the forebrain, evoked compound action potential (CAP) recordings from cerebellar white matter of Sprague-Dawley rats indicated a spatial and temporal pattern of electrophysiological deficits throughout the cerebellar vermis. The posterior and middle lobules of the cerebellum exhibited significant declines in evoked CAP amplitude compared to sham controls (p=0.004, p=0.005, respectively). Duration of the CAP decay also increased, suggesting that functional white matter deficits were a combination of axonal loss and compromised axonal integrity. Functional white matter deficits persisted at 14 days post-injury in the posterior and middle regions of the cerebellum. Evidence of heavy chain neurofilament (NF200) degradation was observed at 1 day post-injury by Western blot. Immunohistochemistry labeling for NF200 indicated the presence of highly immunoreactive NF200 axonal swellings consistent with morphological features of TAI. alpha-Spectrin degradation was also observed between 1 and 14 days post-injury. This study demonstrates the electrophysiological consequences of cerebellar white matter injury and a temporal profile of NF200 and spectrin degradation following forebrain FPI.

Action Potentials↗
PubMed2005

Lymphomatosis cerebri as a cause of white matter dementia.

Primary central nervous system lymphoma most often presents as a solitary, isolated lesion in immunocompetent patients. Rarely, the disease presents as a diffuse, infiltrating condition without formation of a cohesive mass, a pattern called lymphomatosis cerebri. We present 3 immunocompetent individuals who developed rapidly progressive dementia. Magnetic resonance imaging features mimicked other disorders of white matter and prompted preoperative diagnoses of Binswanger's disease (subcortical ischemic vascular dementia), unknown leukoencephalopathy, viral infection, or infiltrating glioma. Neuropathologic examination at biopsy (Poon T, Matoso I, Tchertkoff V, Weitzner I Jr, Gade M. CT features of primary cerebral lymphoma in AIDS and non-AIDS patients. J Comput Assist Tomogr . 1989;13:6-9) and autopsy (Schwaighofer BW, Hesselink JR, Press GA, Wolf RL, Healy ME, Berthoty DP. Primary intracranial CNS lymphoma: MR manifestations. Am J Neuroradiol . 1993;10:725-9) demonstrated nonnecrotic, diffusely infiltrating, large-cell B-cell lymphoma of white matter, with relative sparing of gray matter, and without significant leptomeningeal involvement or bulky periventricular disease at autopsy. Microglial and astrocytic reactions, but only subtle myelin pallor, were evident as individual tumor cells permeated the entire brain and spinal cord, albeit with considerable variation in cell density. Individual tumor cells could be identified from the optic nerve to spinal cord, documenting the "whole-brain" nature of the disease. CD20 immunostaining was necessary to fully appreciate the extent of individual lymphoma cell percolation through the white matter. The neurobehavioral deficits manifested by these patients demonstrate that lymphomatosis cerebri is an additional neoplastic cause of white matter dementia and can be added to the growing list of disorders responsible for this syndrome.

Aged↗
PubMed2006

Increased cerebellar vermis white-matter volume in men with schizophrenia.

We aimed to investigate cerebellar structural abnormalities and their functional significance in patients with schizophrenia. Forty right-handed men with schizophrenia and 40 sex, age and handedness matched controls underwent a volumetric magnetic resonance scan with 1 mm3 isotropic spatial resolution. Cerebellar grey- and white-matter volumes were analysed using voxel-based morphometry. Patients with schizophrenia completed a battery of neuropsychological tests assessing sustained attention (continuous performance test), memory (Hopkins memory test) and executive function (verbal fluency and Wisconsin card sorting tests). Patients with schizophrenia exhibited significantly increased cerebellar vermis white-matter volume compared with controls. By contrast, total cerebellar volume, and grey- and white-matter volumes of cerebellar hemispheres were not significantly different between groups. Increased vermis white-matter volume in patients was associated with poor verbal fluency performance. We concluded that increased white-matter in the cerebellar vermis, possibly suggesting anomalous connectivity, may be associated with verbal executive dysfunction in men with chronic schizophrenia.

Adult↗
PubMed2005

Impact of sediment organic matter quality on the fate and effects of fluoranthene in the infaunal brittle star Amphiura filiformis.

Hydrophobic contaminants, such as polycyclic aromatic hydrocarbons (PAHs) readily adsorb to organic matter. The aim of this study was to determine the importance of the quality of sedimentary organic matter for the uptake, biotransformation and toxicity of the PAH, fluoranthene (Flu), in the infaunal brittle star Amphiura filiformis. Brittle stars were exposed to a base sediment covered by a 2 cm Flu-spiked top layer (30 microg Flu/g dry wt. sed.), enriched to the same total organic carbon content with either refractory or labile organic matter. The labile carbon source was concentrated green flagellate: Tetraselmis spp. The refractory carbon source was lignin from a paper mill. Tissue concentrations of Flu both in disk and arm-fractions were determined as total Flu, parent Flu (i.e. untransformed), aqueous Flu-metabolites, polar Flu-metabolites and tissue residue Flu (i.e. unextractable). Our results showed that sediment particle ingestion is a pathway by which Flu can enter benthic food webs. Flu toxicity (measured as arm-regeneration), but not net accumulation, was dependent on the nutritional quality of the ingested sediment particles. Flu bioaccumulation could not be attributed solely to equilibrium partitioning between organism lipid content and organic content of the sediment. Biotransformation of Flu by brittle stars was very limited and unaffected by organic matter quality. A. filiformis contributed to the downward transport of Flu from the surface sediment to the burrow lining. The limited breakdown of parent Flu by brittle stars and/or microorganisms was relatively higher in burrows compared to surface sediment, and highest in the presence of labile organic matter. Tissue concentrations were higher in disk than in arms, but the proportion of metabolic products relative to parent Flu was higher in arms than in the disk fraction. We estimate that the yearly mobilization of sediment-associated Flu by arm-regeneration in A. filiformis is in the range of 3.8-29.4 microg total Flu eq. m(-2) year(-1) at a sediment concentration of 30 microg Flu/g dry wt. sed.

Animals↗
PubMed2005

Ontogeny of AMPA and NMDA receptor gene expression in the developing sheep white matter and cerebral cortex.

This study examined the hypothesis that the high prevalence of white matter injury in premature infants is associated with increased expression of calcium-permeable forms of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) subtype of glutamate receptors in pre-myelinating white matter. We characterized expression of subunits of the AMPA, and for reference, the N-methyl-d-aspartate (NMDA), glutamate receptors at 0.5, 0.65, 0.85, and term gestation in the ovine fetal white matter and cerebral cortex. There was a low expression of the critical calcium-impermeable AMPA receptor GluR2 subunit in subcortical white matter both absolutely and relative to other AMPA subunits throughout gestation. In contrast, GluR2 subunit mRNA expression fell in the cerebral cortex with increasing gestation whereas protein expression increased. These findings suggest a vulnerability of subcortical white matter to AMPA receptor-mediated calcium toxicity throughout the second half of gestation. Thus, the hypothesis that AMPA receptor-mediated glutamate toxicity contributes to brain damage in premature infants needs to be revised.

Age Factors↗
PubMed2006

Principal component and linear discriminant analysis of T1 histograms of white and grey matter in multiple sclerosis.

Twenty-three relapsing remitting multiple sclerosis (RRMS) patients and 14 controls were imaged to produce normal-appearing white and grey matter T1 histograms. These were used to assess whether histogram measures from principal component analysis (PCA) and linear discriminant analysis (LDA) out-perform traditional histogram metrics in classification of T1 histograms into control and RRMS subject groups and in correlation with the expanded disability status score (EDSS). The histograms were classified into one of two groups using a leave-one-out analysis. In addition, the patients were scanned serially, and the calculated parameters correlated with the EDSS. The classification results showed that the more complex techniques were at least as good at classifying the subjects as histogram mean, peak height and peak location, with PCA/LDA having success rates of 76% for white matter and 68%/65% for grey matter. No significant correlations were found with EDSS for any histogram parameter. These results indicate that there is much information contained within the grey matter as well as the white matter histograms. Although in these histograms PCA and LDA did not add greatly to the discriminatory power of traditional histogram parameters, they provide marginally better performance, while relying only on data-driven feature selection.

Brain↗