These scripts have now been integrated in a toolbox, we recommend using the newer version:https://github.com/mb-BCA/notebooks_review2019
These scripts in Python 3 are a small package to analyze fMRI signals. It is a collaborative work with Andrea Insabato, Vicente Pallarés, Gorka Zamora-López and Nikos Kouvaris. If you use this toolbox, please cite the relevant papers below.
Whole-brain linear effective connectivity (WBLEC) estimation
The script ParameterEstimation.py calculates the spatiotemporal functional connectivity for each session (or run) and subject from the BOLD time series. Then, it calls the model optimization (function in WBLECmodel.py) and stores the model estimates (effective connectivity matrix embedded in the Jacobian J and input variances Sigma) in an array. The data are:
- BOLD time series in ts_emp.npy
- structural connectivity in SC_anat.npy
- ROI labels in ROI_labels.npy
Classification
The script Classification.py compares the performances of two classifiers (multinomial linear regressor and 1-nearest-neighbor) in identifying subjects from EC taken as a biomarker.
The script FeatureSelection.py performs recursive feature elimination to identify the most informative EC connections for the rest-movie classification. It compares the resulting ranking for EC connections to the p-values obtained with statistical testing.
References
Data are from: Gilson M, Deco G, Friston K, Hagmann P, Mantini D, Betti V, Romani GL, Corbetta M. Effective connectivity inferred from fMRI transition dynamics during movie viewing points to a balanced reconfiguration of cortical interactions. Neuroimage 2018, 180: 534-546; http://doi.org/10.1016/j.neuroimage.2017.09.061. See also: Hlinka J, Palus M, Vejmelka M, Mantini D, Corbetta M. Functional connectivity in resting-state fMRI: is linear correlation sufficient? Neuroimage 2011, 54:2218-2225; http://doi.org/10.1016/j.neuroimage.2010.08.042
Model optimization is described in: Gilson M, Moreno-Bote R, Ponce-Alvarez A, Ritter P, Deco G. Estimation of Directed Effective Connectivity from fMRI Functional Connectivity Hints at Asymmetries of Cortical Connectome. PLoS Comput Biol 2016, 12: e1004762; http://dx.doi.org/10.1371/journal.pcbi.1004762
Classification procedure is described in: Pallarés V, Insabato A, Sanjuan A, Kühn S, Mantini D, Deco G, Gilson M. Subject- and behavior-specific signatures extracted from fMRI data using whole-brain effective connectivity. Neuroimage 2018, 178: 238-254; http://doi.org/10.1016/j.neuroimage.2018.04.070
The classification script uses the scikit.learn library (http://scikit-learn.org)