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Bidirectional gray matter changes after complex motor skill learning  [PDF]
Marco Taubert,Juergen Dukart,Virginia Conde,Bernhard Sehm,Arno Villringer,Patrick Ragert
Frontiers in Systems Neuroscience , 2012, DOI: 10.3389/fnsys.2012.00037
Abstract: Long-term motor skill learning has been consistently shown to result in functional as well as structural changes in the adult human brain. However, the effect of short learning periods on brain structure is not well understood. In the present study, subjects performed a sequential pinch force task (SPFT) for 20 min on 5 consecutive days. Changes in brain structure were evaluated with anatomical magnetic resonance imaging (MRI) scans acquired on the first and last day of motor skill learning. Behaviorally, the SPFT resulted in sequence-specific learning with the trained (right) hand. Structural gray matter (GM) alterations in left M1, right ventral premotor cortex (PMC) and right dorsolateral prefrontal cortex (DLPFC) correlated with performance improvements in the SPFT. More specifically we found that subjects with strong sequence-specific performance improvements in the SPFT also had larger increases in GM volume in the respective brain areas. On the other hand, subjects with small behavioral gains either showed no change or even a decrease in GM volume during the time course of learning. Furthermore, cerebellar GM volume before motor skill learning predicted (A) individual learning-related changes in the SPFT and (B) the amount of structural changes in left M1, right ventral PMC and DLPFC. In summary, we provide novel evidence that short-term motor skill learning is associated with learning-related structural brain alterations. Additionally, we showed that practicing a motor skill is not exclusively accompanied by increased GM volume. Instead, bidirectional structural alterations explained the variability of the individual learning success.
Motor Learning in Healthy Humans Is Associated to Gray Matter Changes: A Tensor-Based Morphometry Study  [PDF]
Massimo Filippi,Antonia Ceccarelli,Elisabetta Pagani,Roberto Gatti,Alice Rossi,Laura Stefanelli,Andrea Falini,Giancarlo Comi,Maria Assunta Rocca
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0010198
Abstract: We used tensor-based morphometry (TBM) to: 1) map gray matter (GM) volume changes associated with motor learning in young healthy individuals; 2) evaluate if GM changes persist three months after cessation of motor training; and 3) assess whether the use of different schemes of motor training during the learning phase could lead to volume modifications of specific GM structures. From 31 healthy subjects, motor functional assessment and brain 3D T1-weighted sequence were obtained: before motor training (time 0), at the end of training (two weeks) (time 2), and three months later (time 3). Fifteen subjects (group A) were trained with goal-directed motor sequences, and 16 (group B) with non purposeful motor actions of the right hand. At time 1 vs. time 0, the whole sample of subjects had GM volume increase in regions of the temporo-occipital lobes, inferior parietal lobule (IPL) and middle frontal gyrus, while at time 2 vs. time 1, an increased GM volume in the middle temporal gyrus was seen. At time 1 vs. time 0, compared to group B, group A had a GM volume increase of the hippocampi, while the opposite comparison showed greater GM volume increase in the IPL and insula in group B vs. group A. Motor learning results in structural GM changes of different brain areas which are part of specific neuronal networks and tend to persist after training is stopped. The scheme applied during the learning phase influences the pattern of such structural changes.
Effect of Bcl-2 rs956572 Polymorphism on Age-Related Gray Matter Volume Changes  [PDF]
Mu-En Liu, Chu-Chung Huang, Albert C. Yang, Pei-Chi Tu, Heng-Liang Yeh, Chen-Jee Hong, Jin-Fan Chen, Ying-Jay Liou, Ching-Po Lin, Shih-Jen Tsai
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0056663
Abstract: The anti-apoptotic protein B-cell CLL/lymphoma 2 (Bcl-2) gene is a major regulator of neural plasticity and cellular resilience. Recently, the Bcl-2 rs956572 single nucleotide polymorphism was proposed to be a functional allelic variant that modulates cellular vulnerability to apoptosis. Our cross-sectional study investigated the genetic effect of this Bcl-2 polymorphism on age-related decreases in gray matter (GM) volume across the adult lifespan. Our sample comprised 330 healthy volunteers (191 male, 139 female) with a mean age of 56.2±22.0 years (range: 21–92). Magnetic resonance imaging and genotyping of the Bcl-2 rs956572 were performed for each participant. The differences in regional GM volumes between G homozygotes and A-allele carriers were tested using optimized voxel-based morphometry. The association between the Bcl-2 rs956572 polymorphism and age was a predictor of regional GM volumes in the right cerebellum, bilateral lingual gyrus, right middle temporal gyrus, and right parahippocampal gyrus. We found that the volume of these five regions decreased with increasing age (all P<.001). Moreover, the downward slope was steeper among the Bcl-2 rs956572 A-allele carriers than in the G-homozygous participants. Our data provide convergent evidence for the genetic effect of the Bcl-2 functional allelic variant in brain aging. The rs956572 G-allele, which is associated with significantly higher Bcl-2 protein expression and diminished cellular sensitivity to stress-induced apoptosis, conferred a protective effect against age-related changes in brain GM volume, particularly in the cerebellum.
Regional gray matter volumetric changes in autism associated with social and repetitive behavior symptoms
Donald C Rojas, Eric Peterson, Erin Winterrowd, Martin L Reite, Sally J Rogers, Jason R Tregellas
BMC Psychiatry , 2006, DOI: 10.1186/1471-244x-6-56
Abstract: We performed MRI scans on 24 individuals diagnosed with DSM-IV autistic disorder and compared those to scans from 23 healthy comparison subjects matched on age. All participants were male. Whole brain, voxel-wise analyses of regional gray matter volume were conducted using voxel-based morphometry (VBM).Controlling for age and total gray matter volume, the volumes of the medial frontal gyri, left pre-central gyrus, right post-central gyrus, right fusiform gyrus, caudate nuclei and the left hippocampus were larger in the autism group relative to controls. Regions exhibiting smaller volumes in the autism group were observed exclusively in the cerebellum. Significant partial correlations were found between the volumes of the caudate nuclei, multiple frontal and temporal regions, the cerebellum and a measure of repetitive behaviors, controlling for total gray matter volume. Social and communication deficits in autism were also associated with caudate, cerebellar, and precuneus volumes, as well as with frontal and temporal lobe regional volumes.Gray matter enlargement was observed in areas that have been functionally identified as important in social-cognitive processes, such as the medial frontal gyri, sensorimotor cortex and middle temporal gyrus. Additionally, we have shown that VBM is sensitive to associations between social and repetitive behaviors and regional brain volumes in autism.Studies of volumetric quantification of magnetic resonance imaging (MRI) data in autism have largely been non-replicative. To illustrate with a single example of considerable theoretical importance to autism, interest in hippocampal volume has been high since the neuropathology studies of Bauman and Kemper [1] reported evidence of increased cell packing density and reduced cell size in the hippocampus. However, as pointed out in two recent articles [2,3], there is little agreement between studies measuring hippocampal volume in individuals with autism. To date, there are 4 studies repor
精神分裂症患者急性期药物治疗前后的脑灰质变化
Changes of cerebral gray matter pre- and post-treatment in patients with schizophrenia
 [PDF]

项琼,王颖婵,朱殿明,卓恺明,王征,徐一峰,刘登堂
XIANG Qiong
, WANG Ying-chan, ZHU Dian-ming, ZHUO Kai-ming, WANG Zheng, XU Yi-feng, LIU Deng-tang

- , 2017, DOI: 10.3969/j.issn.1674-8115.2017.02.014
Abstract: 目的 ·探讨短期药物治疗对精神分裂症急性期患者大脑结构(尤其是灰质)的影响。方法 ·共 27例未服药的早期精神分裂症患者(病程不超过5年)和21名健康志愿者入组,其中27例患者接受抗精神病药物治疗8周,分别于基线及8周后(21例)精神分裂症患者及21例健康志愿者)进行3T磁共振扫描。使用基于体素的形态学分析(VBM)方法分析大脑灰质体积及其变化。结果 ·与健康对照组比较,精神分裂症患者的左侧小脑后叶、左侧颞中回及双侧海马旁回的灰质容积减少(P=0.000,体素>50)。8周后随访,健康对照组的灰质体积无变化。经抗精神病药物治疗8周后,精神分裂症患者较多脑区的灰质容积缩小,主要包括双侧颞上回、颞中回、颞下回,双侧额上回、额中回、额下回,双侧海马旁回及扣带回,右侧缘上回,右侧小脑后叶,右侧舌状回(P=0.000,体素>50)。结论 ·抗精神病药物短期治疗(8周)对急性期精神分裂症患者的大脑灰质可能产生不利影响,引起灰质体积的缩小。
: Objective · To observe the changes of cerebral gray matter pre- and post-treatment with short term drugs in patients with schizophrenia. Methods · T1-weighted brain MRIs were obtained on a 3T scanner in 21 controls and 27 subjects with schizophrenia who were not given antipsychotic medication. The controls and 21 schizophrenia patients received the second scan after 8 weeks of antipsychotic treatment. Voxel-based morphometry (VBM) were used to investigate the differences in gray matter (GM), mainly about the regional GM volumes. Results · GM volumes were significantly smaller in the patient group than those of healthy controls in left cerebellum posterior lobe , left and right parahippocampalgyrus, left middle temporal gyrus(P=0.000, voxels>50). GM volumes extensively decreased after 8 weeks of antipsychotic-treatment compared with pre-treatment in the superior, middle, and inferior temporal gyri, superior,middle and inferior frontal gyri, parahippocampa gyri, cingulate gyri, right supramarginal gyrus, right cerebellum posterior lobe, and right lingual gyrus(P=0.000, voxels>50). Conclusion · Short term antipsychotic treatment (8 weeks) may have adverse effects on the gray matter of patients with acute schizophrenia by reducing the volume of gray matter
Gray Matter Pathology in MS: Neuroimaging and Clinical Correlations  [PDF]
Justin Morris Honce
Multiple Sclerosis International , 2013, DOI: 10.1155/2013/627870
Abstract: It is abundantly clear that there is extensive gray matter pathology occurring in multiple sclerosis. While attention to gray matter pathology was initially limited to studies of autopsy specimens and biopsies, the development of new MRI techniques has allowed assessment of gray matter pathology in vivo. Current MRI techniques allow the direct visualization of gray matter demyelinating lesions, the quantification of diffuse damage to normal appearing gray matter, and the direct measurement of gray matter atrophy. Gray matter demyelination (both focal and diffuse) and gray matter atrophy are found in the very earliest stages of multiple sclerosis and are progressive over time. Accumulation of gray matter damage has substantial impact on the lives of multiple sclerosis patients; a growing body of the literature demonstrates correlations between gray matter pathology and various measures of both clinical disability and cognitive impairment. The effect of disease modifying therapies on the rate accumulation of gray matter pathology in MS has been investigated. This review focuses on the neuroimaging of gray matter pathology in MS, the effect of the accumulation of gray matter pathology on clinical and cognitive disability, and the effect of disease-modifying agents on various measures of gray matter damage. 1. Background Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS); focal areas of white matter demyelination have long been considered the key feature of MS [1]. Despite this belief that MS is primarily a white matter disease, early pathologic studies had reported focal areas of cortical demyelination in MS patients [2, 3]. In 1962, Brownell and Hughes [4] showed that, in MS, cortical demyelinating lesions represented up to 26% of the total number of cerebral plaques. Despite these early indications of the cortical pathology occurring in MS, in general very little attention was paid to cortical pathology. It is likely that this was due to both the difficulty in identifying cortical lesions at autopsy via conventional histochemical techniques and the marked conspicuity of inflammatory lesions in the white matter [5]. This focus on white matter demyelination rather than cortical pathology was initially compounded with the advent of MRI: conventional MRI techniques for imaging MS identify a majority of focal white matter lesions but are very insensitive for the detection of cortical MS lesions [6]. Despite initial focus on white matter demyelination, there has been increasing focus on the gray matter
Working Memory Training Using Mental Calculation Impacts Regional Gray Matter of the Frontal and Parietal Regions  [PDF]
Hikaru Takeuchi, Yasuyuki Taki, Yuko Sassa, Hiroshi Hashizume, Atsushi Sekiguchi, Ai Fukushima, Ryuta Kawashima
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0023175
Abstract: Training working memory (WM) improves performance on untrained cognitive tasks and alters functional activity. However, WM training's effects on gray matter morphology and a wide range of cognitive tasks are still unknown. We investigated this issue using voxel-based morphometry (VBM), various psychological measures, such as non-trained WM tasks and a creativity task, and intensive adaptive training of WM using mental calculations (IATWMMC), all of which are typical WM tasks. IATWMMC was associated with reduced regional gray matter volume in the bilateral fronto-parietal regions and the left superior temporal gyrus. It improved verbal letter span and complex arithmetic ability, but deteriorated creativity. These results confirm the training-induced plasticity in psychological mechanisms and the plasticity of gray matter structures in regions that have been assumed to be under strong genetic control.
Cortical Depth Dependence of the Diffusion Anisotropy in the Human Cortical Gray Matter In Vivo  [PDF]
Trong-Kha Truong, Arnaud Guidon, Allen W. Song
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0091424
Abstract: Diffusion tensor imaging (DTI) is typically used to study white matter fiber pathways, but may also be valuable to assess the microstructure of cortical gray matter. Although cortical diffusion anisotropy has previously been observed in vivo, its cortical depth dependence has mostly been examined in high-resolution ex vivo studies. This study thus aims to investigate the cortical depth dependence of the diffusion anisotropy in the human cortex in vivo on a clinical 3 T scanner. Specifically, a novel multishot constant-density spiral DTI technique with inherent correction of motion-induced phase errors was used to achieve a high spatial resolution (0.625×0.625×3 mm) and high spatial fidelity with no scan time penalty. The results show: (i) a diffusion anisotropy in the cortical gray matter, with a primarily radial diffusion orientation, as observed in previous ex vivo and in vivo studies, and (ii) a cortical depth dependence of the fractional anisotropy, with consistently higher values in the middle cortical lamina than in the deep and superficial cortical laminae, as observed in previous ex vivo studies. These results, which are consistent across subjects, demonstrate the feasibility of this technique for investigating the cortical depth dependence of the diffusion anisotropy in the human cortex in vivo.
应用基于体素的形态测量学方法分析原发性手震颤患者灰质体积变化
Brain gray matter changes in essential arm tremor patients: Voxel-based morphometry
 [PDF]

曹红梅,,,李贤军,,,,,屈秋民
- , 2015, DOI: 10.7652/jdyxb201504017
Abstract: 摘要:目的 评价单纯手震颤的原发性震颤(essential tremor, ET)患者脑内灰质体积变化。方法 选取l7例临床确诊的,年龄小于55岁的单纯手震颤ET患者及17名年龄、性别、教育程度匹配的正常对照者,行全脑三维快速扰相梯度回波(3D fast spoiled gradient echo, 3D FSPGR)序列扫描,采用基于体素的形态测量学(voxel-based morphometry, VBM)分析方法,对ET患者及正常对照者的脑内灰质体素进行分析。结果 与正常对照组相比,ET患者脑内可见双侧小脑半球前叶、枕叶、颞叶及中央前回体积增大以及左侧顶叶体积缩小(Puncorrected<0.005);进一步的感兴趣区(region-of-interest, ROI)测定发现左侧丘脑、中脑及延髓体积膨大,桥脑体积缩小(Puncorrected<0.005)。结论 应用VBM方法对于单纯手震颤ET患者磁共振图像分析,能够客观揭示其脑内独特的灰质体积改变,有助于进一步探讨ET的发病机制。
ABSTRACT: Objective To investigate the abnormalities of brain gray matter volume in patients with clinically-confirmed essential tremor (ET) of the hands only. Methods We analyzed brain gray matter voxel of 17 patients (younger than 55 years) with ET of the hands only and 17 healthy controls matched in age, gender and education by optimized voxel-based morphometry (VBM). Results VBM showed marked expansion of the bilateral cerebella, occipital fusiform cortices, and precentral lobes (Puncorrected <0.005) in ET patients compared with the controls. Atrophy was only detected in left parietal lobe. We also found volume enlargement in the thalamus, midbrain, and melluda of the left side by region of interest (ROI ) analysis (Puncorrected<0.005). Conclusion Patients with arm tremor show expansion of gray matter, which might represent the adaptive reorganizational compensation through the increased demand on the visuospatial control of skilled movements in ET patients with early-stage arm tremor. These morphological changes may help to assess early stage and distinguish subtype of ET
Assessment of gray matter heterotopia by magnetic resonance imaging  [cached]
Ragab H Donkol,Khaled M Moghazy,Alaeddin Abolenin
World Journal of Radiology , 2012, DOI: 10.4329/wjr.v4.i3.90
Abstract: AIM: To evaluate magnetic resonance imaging (MRI) features of different types of gray matter heterotopia. METHODS: Between June 2005 and December 2009, the medical records and MRI studies of patients with gray matter heterotopia were reviewed. The MRI morphologic findings of heterotopia were recorded along with the presence and type of associated cranial malformations. Available clinical and electrophysiological data were also recorded. RESULTS: 20 patients were included in the study. Their ages ranged from 9 mo to 39 years with a mean age of 15 years. All patients suffered from epileptic seizures. According to the location of heterotopia, patients were classified into three groups: subependymal (12), subcortical (5) and band (3) heterotopia. CONCLUSION: MRI was useful in diagnosing and differentiating between various types of gray matter heterotopia. The severity of clinical manifestations of heterotopia was related to the location and pattern of heterotopia. Determination of heterotopia type and its extent is useful for management planning and predicting prognosis.
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