A multiscale method for a robust detection of the Default Mode Network

摘要

The Default Mode Network (DMN) is a resting state network widely used for the analysis and diagnosis of mental disorders. It is normally detected in resting-state fMRI data, but for its detection in data corrupted by motion artifacts or low neuronal activity, the use of a robust analysis method is mandatory. In fMRI it has been shown that the signal-to-noise ratio and the detection sensitivity of neuronal regions is increased with different smoothing kernels sizes. Here we propose to use a multiscale decomposition based on a linear scale-space representation for the detection of the DMN. Three main points are proposed in this methodology: first, the use of fMRI data at different smoothing scale-spaces; second, detection of independent neuronal components of the DMN at each scale by using standard preprocessing methods and independent component analysis decomposition at scale-level; and third, a weighted contribution of each scale by the goodness of fit measurement. This method was applied to a group of control subjects and was compared with a standard preprocessing baseline. The detection of the DMN was improved at the single subject level and at the group level. Based on these results, we suggest to use this methodology to enhance the detection of the DMN in data perturbed with artifacts or in data of subjects with low neuronal activity. Furthermore, the multiscale method could be extended for the detection of other resting state neuronal networks.