Voxel-based Regression Analysis Research Articles

A voxel-based morphometry study of semantic deficits in alzheimer?s disease and mild cognitive impairment patients

Event Abstract Back to Event A voxel-based morphometry study of semantic deficits in alzheimer’s disease and mild cognitive impairment patients Javier Rodríguez-Ferreiro1*, Fernando Cuetos2, Asunción Monsalve2, Carmen Martínez3, Ana Julia Pérez3 and Annalena Venneri4, 5 1 Universitat de Barcelona, Spain 2 Universidad de Oviedo, Spain 3 Hospital de Cabueñes, Spain 4 University of Hull, United Kingdom 5 San Camillo Hospital (IRCCS), Italy The aim of this study was to determine the brain areas responsible for the semantic impairment observed in Alzheimer’s disease (AD) and Mild Cognitive Impairment (MCI) patients. Thirteen 13 AD, 14 MCI patients, and 13 matched healthy seniors were assessed with a test battery aimed to study their semantic competence. Different subtasks were designed to study their semantic knowledge related to objects and faces in the context of semantic retrieval- and semantic association-dependent tasks. Aggregate scores obtained in the different tests were entered into voxel-based regression analyses with grey matter volume values obtained from three-dimensional brain MRI scans. Areas of significant correlation between volume loss and poor semantic scores were restricted to the temporal lobe in the AD group, while in the MCI and control groups significant associations were found with lower grey matter volume values in a network of bilateral fronto-temporo-parietal regions. Our results suggest that degradation of partially overlapping and widely distributed neural networks, mainly including temporal regions, subserve semantic deficits related to objects and faces in AD and MCI patients. Keywords: AD, Aging, MCI Conference: XI International Conference on Cognitive Neuroscience (ICON XI), Palma, Mallorca, Spain, 25 Sep - 29 Sep, 2011. Presentation Type: Poster Presentation Topic: Poster Sessions: Cognitive Aging Citation: Rodríguez-Ferreiro J, Cuetos F, Monsalve A, Martínez C, Pérez A and Venneri A (2011). A voxel-based morphometry study of semantic deficits in alzheimer’s disease and mild cognitive impairment patients. Conference Abstract: XI International Conference on Cognitive Neuroscience (ICON XI). doi: 10.3389/conf.fnhum.2011.207.00546 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 15 Nov 2011; Published Online: 28 Nov 2011. * Correspondence: Dr. Javier Rodríguez-Ferreiro, Universitat de Barcelona, Barcelona, Spain, xabelferreiro@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Javier Rodríguez-Ferreiro Fernando Cuetos Asunción Monsalve Carmen Martínez Ana Julia Pérez Annalena Venneri Google Javier Rodríguez-Ferreiro Fernando Cuetos Asunción Monsalve Carmen Martínez Ana Julia Pérez Annalena Venneri Google Scholar Javier Rodríguez-Ferreiro Fernando Cuetos Asunción Monsalve Carmen Martínez Ana Julia Pérez Annalena Venneri PubMed Javier Rodríguez-Ferreiro Fernando Cuetos Asunción Monsalve Carmen Martínez Ana Julia Pérez Annalena Venneri Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Subjective cognitive complaints and longitudinal changes in memory and brain function.

Subjective cognitive complaints are often used in the diagnosis of memory and other cognitive impairment. This study examined whether cognitive complaints are associated with longitudinal changes in cognition and cross-sectional differences in regional brain function during memory performance in 98 participants with a mean age of 75. The Cognitive Failures Questionnaire (CFQ) assessed cognitive complaints and mixed effects regression models were used to determine whether mean CFQ scores predicted rates of change in cognitive function over a period of 11.5 years. Higher CFQ scores, reflecting increased subjective complaints, were associated with steeper rates of decline in immediate and delayed recall on the California Verbal Learning Test. Voxel-based regression analysis was used to determine the cross-sectional relationship between CFQ scores and regional cerebral blood flow measured by PET during a resting condition and during verbal and figural memory tasks. Higher levels of cognitive complaints were associated with increased activity in insular, lingual and cerebellar areas during memory tasks. These findings offer some support for the validity of subjective cognitive complaints as markers of age related changes in memory and brain activity.

The pathophysiology of prospective memory failure after diffuse axonal injury - Lesion-symptom analysis using diffusion tensor imaging

BackgroundProspective memory (PM) is one of the most important cognitive domains in everyday life. The neuronal basis of PM has been examined by a large number of neuroimaging and neuropsychological studies, and it has been suggested that several cerebral domains contribute to PM. For these activation studies, a constellation of experimental PM trials was developed and adopted to healthy subjects. In the present study, we used a widely used clinical PM assessment battery to determine the lesions attributable to PM failure, with the hypothesis that lesion-symptom analysis using diffusion tensor imaging (DTI) in subjects with diffuse axonal injury (DAI) can reveal the neuronal basis of PM in everyday life.ResultsFourteen DAI patients (age: range of 18-36, median 24) participated in this study. PM failure was scored in the range of 0-6 using three sub-tests of the Rivermead Behavioural Memory Test. The PM scores of DAI patients were in the range of 2-6 (median 4.5, inter-quartile range 2.25). The severity of axonal injury following DAI was examined using fractional anisotropy (FA), one of the DTI parameters, at voxel level in each subject. We then obtained clusters correlated with PM failure by conducting voxel-based regression analysis between FA values and PM scores. Three clusters exhibited significant positive correlation with PM score, the left parahippocampal gyrus, left inferior parietal lobe, and left anterior cingulate.ConclusionsThis is the first lesion-symptom study to reveal the neuronal basis of PM using DTI on subjects with DAI. Our findings suggest that the neuronal basis of PM is in the left parahippocampal gyrus, left inferior parietal lobe, and/or left anterior cingulate. These findings are similar to those of previous activation studies with loading experimental PM tasks.

FDG-PET mapping the brain substrates of visuo-constructive processing in Alzheimer´s disease

The anatomical basis of visuo-constructive impairment in AD is widely unexplored. FDG-PET can be used to determine functional neuronal networks underlying specific cognitive performance in the human brain. In the present study, we determined the pattern of cortical metabolism that was associated with visuo-constructive performance in AD. We employed two widely used visuo-constructive tests that differ in their demand on visual perception and processing capacity. Resting state FDG-PET scans were obtained in 29 probable AD patients, and cognitive tests were administered. We made a voxel-based regression analysis of FDG uptake to scores in visual test performance, using the SPM5 software. Performance in the CERAD Drawing test correlated with FDG uptake in the bilateral inferior temporal gyri, bilateral precuneus, right cuneus, right supramarginal gyrus and right middle temporal gyrus covering areas of dorsal and ventral visual streams. In contrast, performance in the more complex RBANS Figure Copy test correlated with FDG uptake in the bilateral fusiform gyri, right inferior temporal gyrus, left anterior cingulate gyrus, left parahippocampal gyrus, right middle temporal gyrus and right insula, encompassing the ventral visual stream and areas of higher-level visual processing. The study revealed neuronal networks underlying impaired visual test performance in AD. The extent of involvement of visual and higher order association cortex increased with greater test complexity. From a clinical point of view, both of these widely used visual tests evaluate the integrity of complementary cortical networks and may contribute complementary information on the integrity of visual processing in AD.

Beta Amyloid in Alzheimer's Disease: Increased Deposition in Brain Is Reflected in Reduced Concentration in Cerebrospinal Fluid

A decreased concentration of beta amyloid (1-42) (Abeta42) has consistently been found in the cerebrospinal fluid (CSF) of patients with Alzheimer's disease (AD) and is considered a diagnostic biomarker. However, it is not clear to which extent CSF Abeta42 levels are reflective of cerebral pathology in AD. The aim of the study was to determine the association between cerebral amyloid plaque load, as measured by means of the positron emission tomography (PET) tracer carbon-11-labeled Pittsburgh Compound B ([11C]PiB) and CSF Abeta42 in AD. A group of 30 patients with probable AD, as defined by established clinical criteria and by an AD-typical pattern of tracer uptake in fluorine-18-labeled fluorodeoxyglucose ([18F]FDG) PET, were included. In all patients, [11C]PiB PET and CSF analysis were performed. The association between amyloid load and CSF Abeta42 levels was examined in three different ways: by linear regression analysis using an overall [11C]PiB value for the entire cerebrum, by correlation analyses using [11C]PiB measurements in anatomically defined regions of interest, and by voxel-based regression analyses. All patients showed a positive [11C]PiB scan demonstrating amyloid deposition. Linear regression analysis revealed a significant inverse correlation between the overall [11C]PiB uptake and CSF Abeta42 levels. Voxel-based regression and regional correlation analyses did not attain statistical significance after correction for multiple comparisons. Numerically, correlation coefficients were higher in brain regions adjacent to CSF spaces. The study demonstrates a moderate linear negative association between cerebral amyloid plaque load and CSF Abeta42 levels in AD patients in vivo and suggests possible regional differences of the association.