Computational protocol: The Lateralization of Intrinsic Networks in the Aging Brain Implicates the Effects of Cognitive Training

Similar protocols

Protocol publication

[…] Pre-processing of fMRI data were conducted using the SPM8 Software Package [statistical parametric mapping]. The slice time correction, 3D motion detection and correction, spatial normalization and resample (3 mm × 3 mm × 3 mm), and spatial smoothing using an isotropic Gaussian kernel (6 mm full width at half maximum) were applied. The processing is identical to that used in prior studies (Chen et al., ; Jiang et al., ). Only the subjects with head motion less than 1.5 mm and 1.5° during fMRI acquisition were included in the following preprocessing. In addition, the translation and rotation of the subjects were assessed by frame wise displacement (FD),where i is the i-th time point, and Δdix=d(i−1)x−dix (similarly for the other head motion/rotation parameters; Power et al., ). No significant differences were found between groups in FD. Additional preprocessing in preparation included voxelwise nuisance correction by regressing out six motion signals. [...] Similar to the approaches in our previous studies (Luo et al., ; Li et al., ), we first conducted spatial group ICA in which two times of data of all subjects were included in one group, using the GIFT Software, version 2.0a. The time courses were temporally concatenated across subjects and reduced by means of principal component analysis in temporal domain, followed by an IC estimation using the FastICA algorithm. This algorithm was repeated 20 times in ICASSO, and the resulting components were clustered to estimate the reliability of the decomposition (Himberg et al., ). Dimension estimation on all subjects was performed using the minimum description length (MDL) criterion to determine the number of independent components (ICs). The ICs were back-constructed for each scans and each subject using the dual-regression approach (Zhang et al., ). Finally, we interrogated all components to identify RSNs. Ten RSNs were chosen based on the average power spectra and spatial map of the components such as in the previous studies (Luo et al., ; Li et al., ). Here, the power spectra of time course of ICs was analyzed, and the power spectra of the selected IC should show the frequency content was mainly concentrated below 0.1 Hz (Beckmann et al., ; Luo et al., ). […]

Pipeline specifications

Software tools SPM, fastICA
Applications Miscellaneous, Functional magnetic resonance imaging
Organisms Homo sapiens