Time filter

Source Type

Matsuda H.,Integrative Brain Imaging Center
Ageing Research Reviews | Year: 2016

MRI based evaluation of brain atrophy is regarded as a valid method to stage the disease and to assess progression in Alzheimer's disease (AD). Volumetric software programs have made it possible to quantify gray matter in the human brain in an automated fashion. At present, voxel based morphometry (VBM) is easily applicable to the routine clinical procedure with a short execution time. The importance of the VBM approach is that it is not biased to one particular structure and is able to assess anatomical differences throughout the brain. Stand-alone VBM software running on Windows, Voxel-based Specific Regional analysis system for AD (VSRAD), has been widely used in the clinical diagnosis of AD in Japan. On the other hand, recent application of graph theory to MRI has made it possible to analyze changes in structural connectivity in AD. © 2016 Elsevier B.V. Source

Hanakawa T.,Integrative Brain Imaging Center | Hanakawa T.,Japan Science and Technology Agency
Journal of Orthopaedic Science | Year: 2012

Deafferentation pain following nerve injury annoys patients, and its management is a challenge in clinical practice. Although the mechanisms underlying deafferentation pain remain poorly understood, progress in the development of multidimensional neuroimaging techniques is casting some light on these issues. Deafferentation pain likely results from reorganization of the nervous system after nerve injury via processes that interact with the substrates for pain perception (the pain matrix). Therapeutic effects of motor cortex stimulation on deafferentation pain suggest that the core mechanisms underlying deafferentation pain also interact with the motor system. Therefore, simultaneous neuroimaging and brain stimulation, an emerging neuroimaging technique, was developed to investigate complicated interactions among motor, somatosensory, and pain systems. In healthy participants, parts of the pain matrix (the anterior cingulate cortex, parietal operculum, and thalamus) show activity during both somatosensory stimulation and brain stimulation to the motor cortex. This finding indicates that motor, somatosensory, and pain systems communicate among each other via the neural network. A better understanding of the plastic mechanisms influencing such cross-talk among these systems will help develop therapeutic interventions using brain stimulation and neurofeedback. © The Japanese Orthopaedic Association 2012. Source

Imabayashi E.,Integrative Brain Imaging Center | Inoue T.,Yokohama City University
Neuroscience Bulletin | Year: 2014

Statistical analysis in neuroimaging (referred to as “neurostatistical imaging”) is important in clinical neurology. Here, neurostatistical imaging and its superiority for diagnosing dementia are reviewed. In neurodegenerative dementia, the proportional distribution of brain perfusion, metabolism, or atrophy is important for understanding the symptoms and status of patients and for identifying regions of pathological damage. Although absolute quantitative changes are important in vascular disease, they are less important than relative values in neurodegenerative dementia. Even under resting conditions in healthy individuals, the distribution of brain perfusion and metabolism is asymmetrical and differs among areas. To detect small changes, statistical analysis such as the Z-score — the number of standard deviations by which a patient’s voxel value differs from the normal mean value — comparing normal controls is useful and also facilitates clinical assessment. Our recent finding of a longitudinal one-year reduction of glucose metabolism around the olfactory tract in Alzheimer’s disease using the recently-developed DARTEL normalization procedure is also presented. Furthermore, a newly-developed procedure to assess brain atrophy with CT-based voxel-based morphometry is illustrated. The promising possibilities of CT in neurostatistical imaging are also presented. © 2014, Shanghai Institutes for Biological Sciences, CAS and Springer-Verlag Berlin Heidelberg. Source

Matsuda H.,Integrative Brain Imaging Center
Brain and Nerve | Year: 2015

Voxel-based morphometry (VBM) using structural brain MRI has been widely used for the early and differential diagnosis and evaluation of disease progression in neuropsychiatric diseases. VBM of MRI data comprises segmentation into gray matter, white matter, and cerebrospinal fluid partitions; anatomical standardization of all the images to the same stereotactic space using linear affine transformation and further non-linear warping and smoothing; and finally performing statistical analysis. Stand-alone VBM software using SPM8 plus DARTEL running on Windows (Voxel-based Specific Regional analysis system for Alzheimer's disease, VSRAD®) has been developed as an adjunct to the clinical assessment. This software provides a Z-score map as a result of the comparison of the patient's MRI with a normal database. Source

Moriguchi Y.,Integrative Brain Imaging Center | Komaki G.,International University of Health and Welfare
BioPsychoSocial Medicine | Year: 2013

Alexithymia refers to difficulty in identifying and expressing one's emotions, and it is related to disturbed emotional regulation. It was originally proposed as a personality trait that plays a central role in psychosomatic diseases. This review of neuroimaging studies on alexithymia suggests that alexithymia is associated with reduced neural responses to emotional stimuli from the external environment, as well as with reduced activity during imagery, in the limbic and paralimbic areas (i.e., amygdala, insula, anterior/posterior cingulate cortex). In contrast, alexithymia is also known to be associated with enhanced neural activity in somatosensory and sensorimotor regions, including the insula. Moreover, neural activity in the medial, prefrontal, and insula cortex was lowered when people with alexithymia were involved in social tasks. Because most neuroimaging studies have been based on sampling by self-reported questionnaires, the contrasted features of neural activities in response to internal and external emotional stimuli need to be elucidated. The social and emotional responses of people with alexithymia are discussed and recommendations for future research are presented. © 2013 Moriguchi and Komaki; licensee BioMed Central Ltd. Source

Discover hidden collaborations