fil ion ucl ac uk/spm/) working on Matlab 2010b (MathWorks, Inc , working on Matlab 2010b (MathWorks, Inc.,, MA, USA). All functional volumes were subjected to standard preprocessing procedures (Friston, Ashburner, Kiebel, & Penny, 2007), including spatial realignment, co-registration with the anatomical scan, normalization [on the Montreal Neurological Institute (MNI)

space with 2 × 2 × 2 mm3 voxels] using the unified segmentation of the anatomical scan and smoothed with an isotropic 6 mm full width half-maximum (FWHM) Gaussian kernel. Time series from each voxel were high-pass filtered (1/128 Hz cutoff) and the preprocessed find protocol functional volumes were then submitted to fixed-effects analysis (i.e., first level analysis, FFX) using a block design, applying the general linear model to each voxel (Friston et al., 1995 and Worsley and Friston, 1995) and using an auto-regressive [AR(1)] function to account for temporal correlations between voxels across the whole brain. Afterwards, the data were submitted to second-level analysis (random effect analysis, RFX) in order to generalize the results for

the population. All conditions were modeled in a full factorial model (ANOVAs) 3 × 2 (F1: condition; F2: task). The coordinates derived from these analyses (cluster maxima) were converted from MNI coordinates to Talairach and Tournoux stereotaxic coordinates using the icbm2tal script ( Lancaster et al., 2007) in order to associate MAPK Inhibitor Library ic50 mafosfamide the results with an anatomical location ( Talairach & Tournoux, 1988). The WFU pickAtlas software ( Maldjian et al., 2004 and Maldjian et al.,

2003) was used to define anatomical locations based on the Talairach Daemon atlas database ( Lancaster et al., 2000) and the automatic anatomical labeling (AAL) tool ( Tzourio-Mazoyer et al., 2002). Anatomical labels were assigned according to the nearest gray matter position. All illustrations are based on this neurological convention. Statistical parametric maps (SPMs) were assessed to determine the brain activation associated with each experimental context (simple effects). Effects were recognized at p < .05 corrected for multiple comparisons at the voxel level (FWE). SPMs were also computed to compare brain activity across tasks in the active condition (dynamic vs static) as well as between AO + MI and AO in the dynamic task. Significant differences were recognized at p < .001, uncorrected at the voxel level but with an extended cluster threshold of 240 contiguous voxels (pcluster < .05; false discovery rate (FDR) corrected) for topological analysis ( Chumbley & Friston, 2009). In this manuscript, all locations are presented in MNI coordinates (x, y, z) and the Tables provide details of the local maxima for each cluster. In the first part of this study, the pattern of brain activation in each experimental task was studied with simple effect comparisons (contrast between task and resting state).

Leave a Reply

Your email address will not be published. Required fields are marked *


You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>