EEG and fMRI coupling and decoupling based on joint independent component analysis (jICA)

•A new method is proposed to estimate the coupling and decoupling of EEG and fMRI.•The method uses the mixing matrix of joint independent component analysis (jICA).•The method is tested on fMRI and EEG to spoken syllables delivered at varying rates.•fMRI/EEG-jICA identified brain networks more sensibly than fMRI multiple regression.•Results show how EEG can be leveraged to inform detection and description of fMRI.