http://precedings.nature.com/tags/neuroimaging Recently posted documents tagged with 'neuroimaging' Nature Publishing Group en Nature Precedings http://precedings.nature.com/images/header_logo.gif http://precedings.nature.com http://dx.doi.org/10.1038/npre.2009.3485.1 Clinical MRI and MRS have promise in molecular imaging. Microimaging techniques offer a promising research tool to get noninvasive data in monitoring the effect of drugs. http://dx.doi.org/10.1038/npre.2009.3485.1 Mon, 03 Aug 2009 18:59:28 UTC Quantitative MRI and MR Spectroscopy of Multiple Sclerosis, Alzheimer’s Disease, Epilepsy and Cancer Microimaging Techniques doi:10.1038/npre.2009.3485.1 2009-08-03 Rakesh Sharma Nature Precedings 2009-08-03T18:59:28Z Presentation Biotechnology Cancer Neuroscience http://creativecommons.org/licenses/by/3.0/ http://precedings.nature.com/documents/2836/version/1 On July 17, 1990, President George Bush issued “Proclamation #6158” which boldly declared the following ten years would be called the “Decade of the Brain” (Bush, 1990). Accordingly, the research mandates of all US federal biomedical institutions worldwide were redirected towards the study of the brain in general and cognitive neuroscience specifically. In 2008, one of the greatest legacies of this “Decade of the Brain” is the impressive array of techniques that can be used to study cortical activity. We now stand at a juncture where cognitive function can be mapped in the time, space and frequency domains, as and when such activity occurs. These advanced techniques have led to discoveries in many fields of research and clinical science, including psychology and psychiatry. Unfortunately, neuroscientific techniques have yet to be enthusiastically adopted by the social sciences. Market researchers, as specialized social scientists, have an unparalleled opportunity to adopt cognitive neuroscientific techniques and significantly redefine the field and possibly even cause substantial dislocations in business models. Following from this is a significant opportunity for more commercially-oriented researchers to employ such techniques in their own offerings. This report examines the feasibility of these techniques. http://precedings.nature.com/documents/2836/version/1 Mon, 09 Feb 2009 16:14:51 UTC The Feasibility of Neuroimaging Methods in Marketing Research hdl:10101/npre.2009.2836.1 2009-02-09 Carl Senior Nature Precedings 2009-02-09T16:14:51Z Manuscript Neuroscience http://creativecommons.org/licenses/by/3.0/ http://dx.doi.org/10.1038/npre.2008.2665.1 In functional magnetic resonance imaging, the brain’s response to experimental cognitive tasks is usually assumed to be independent of endogenous oscillations. To test this assumption, we measured fractal scaling of fMRI time-series before and after a working memory task. Prolonged and task difficulty-related changes in post-task ‘resting’ data suggest that brain dynamics recover slowly from cognitive effort, contrary to the reflexive model that background oscillations are independent of task performance. http://dx.doi.org/10.1038/npre.2008.2665.1 Mon, 22 Dec 2008 11:40:30 UTC Endogenous human brain dynamics recover slowly following cognitive effort doi:10.1038/npre.2008.2665.1 2008-12-22 John Suckling Nature Precedings 2008-12-22T11:40:30Z Manuscript Neuroscience http://creativecommons.org/licenses/by/3.0/ http://precedings.nature.com/documents/2235/version/1 How are objects represented in the human visual pathway? This question continues to elude the neuroimaging field due to at least two kinds of problems: first, the relatively low spatial resolution of fMRI and second, the bias inherent in prevailing statistical methods for analyzing the actual diagnosticity of cortical tissue. We collected high-resolution (1mm x 1mm) imaging data of the fusiform face area (FFA) from 4 subjects while they categorized images as 'animal', 'car', 'face', or 'sculpture.' We performed exploratory analysis to determine the nature of the distributions over classes and the similarity structure between classes. The FFA was visualized using nonmetric multidimensional scaling revealing "string-like" sequences of voxels, which appeared in small non-contiguous clusters of categories, intertwined with other categories. Since the feature space appeared highly nonlinear, we trained various statistical classifiers on the class conditional distributions (labelled) and separated the four categories with 100% reliability (over replications) and generalized to out of sample cases with high significance (45% to 51%; p<. 000001, chance=25%). The increased noise inherent in high-resolution neuroimaging data relative to standard resolution resisted any further gains in category performance above 60% (with "FACE" category often having the highest bias per category) even coupled with various feature extraction/selection methods. A sensitivity/diagnosticity analysis for each classifier per voxel showed: (1) reliable (with S.E.<3%) sensitivity present throughout the FFA for all 4 categories, and (2) showed multi-selectivity, that is, many voxels were selective for one category but responded to all 4 categories with some high diagnosticity but at lower intensity. This work further verifies the hypothesis that the FFA is a distributed, object-heterogeneous similarity structure and bolsters the view that the FFA response to "FACE" stimuli in standard resolution may be primarily due to a linear bias, which has resulted from an averaging artifact. http://precedings.nature.com/documents/2235/version/1 Fri, 29 Aug 2008 13:15:51 UTC High Resolution Imaging of the Fusiform Face Area (FFA) Using Nonlinear Classifiers Shows Diagnosticity for Nonface Categories hdl:10101/npre.2008.2235.1 2008-08-29 Stephen Hanson Nature Precedings 2008-08-29T13:15:51Z Manuscript Neuroscience Bioinformatics http://creativecommons.org/licenses/by/3.0/ http://precedings.nature.com/documents/1966/version/1 Reports of the beneficial effects of the hypnotic imidazopyridine, zolpidem, described in persistent vegetative state1, 2 have been replicated recently in brain-injured and cognitively impaired patients3-7. Previous single photon emission computed tomography (SPECT) studies have suggested that sub-sedative doses of zolpidem increased regional cerebral perfusion in affected areas5, 8, implying enhanced neuronal metabolic activity; which has led to speculation that zolpidem ‘reawakens’ functionally dormant cortex. However, a neuronal mechanism by which this hypnotic drug affords benefits to brain injured patients has yet to be demonstrated. Here, we report the action of sub-sedative doses of zolpidem on neuronal network oscillatory activity in human brain, measured using pharmaco-magnetoencephalography (pharmaco-MEG). Study participant JP suffered a stroke in 1996, causing major damage to the left hemisphere that impaired aspects of both motor and cognitive function. Pharmaco-MEG analyses revealed robust and persistent pathological theta (4-10Hz) and beta (15-30Hz) oscillations within the lesion penumbra and surrounding cortex. Administration of zolpidem (5mg) reduced the power of pathological theta and beta oscillations in all regions of the lesioned hemisphere. This desynchronizing effect correlated well with zolpidem uptake (occurring approximately 40 minutes after acute administration) and was coincident with marked improvements in cognitive and motor function. Control experiments revealed no effect of placebo, while a structurally unrelated hypnotic, zopiclone, administered at a comparable dose (3.5mg) elicited widespread increases in cortical oscillatory power in the beta (15-30Hz) band without functional improvement. These results suggest that in JP, specific motor and cognitive impairments are related to increased low-frequency oscillatory neuronal network activity. Zolpidem is unique amongst hypnotic drugs in its ability to desynchronize such pathological low-frequency activity, thereby restoring cognitive function. http://precedings.nature.com/documents/1966/version/1 Wed, 11 Jun 2008 15:57:56 UTC Desynchronization of pathological low-frequency brain activity by the hypnotic drug zolpidem. hdl:10101/npre.2008.1966.1 2008-06-11 Stephen D. Hall Nature Precedings 2008-06-11T15:57:56Z Manuscript Neuroscience Pharmacology http://creativecommons.org/licenses/by/3.0/ http://dx.doi.org/10.1038/npre.2008.1781.1 The goal of this meeting was to map existing neuroimaging databases, particularly databases containing primary data, and to identify mechanisms that could facilitate integrated use of such databases, including possible fusion of databases. The report provides an overview of existing neuroimaging databases that were discussed during the workshop and examines the feasibility of database federations. The report includes several recommendations for future developments. http://dx.doi.org/10.1038/npre.2008.1781.1 Tue, 08 Apr 2008 17:22:13 UTC 1st INCF Workshop on NeuroImaging Database Integration doi:10.1038/npre.2008.1781.1 2008-04-08 Lars Forsberg Nature Precedings 2008-04-08T17:22:13Z Manuscript Neuroscience Bioinformatics http://creativecommons.org/licenses/by/3.0/