File:Real-Time-fMRI-Pattern-Decoding-and-Neurofeedback-Using-FRIEND-An-FSL-Integrated-BCI-Toolbox-pone.0081658.s003.ogv

English: SVM-based neurofeedback session. Input parameters (reference anatomical and functional images, TR, number of functional volumes, baseline condition, etc) need to be entered into the FRIEND interface before clicking the “Feedback” button on the control window. Motion parameters are shown in the first three graphs during real-time acquisition and processing. This video also shows the “Display Brain Slices” functionality, which allows dynamic visualization of signal changes overlaid on a participant’s coregistered anatomical image. The arbitrary signal threshold can be modified using the “Inf” (inferior level) and “Sup” (superior level) buttons in the control box. These buttons define the value range of the color bar. In this particular example, neurofeedback is provided to the participant using the ring figures, whose color is associated with the condition (positive or negative emotion), level of distortion is dependent on the multivariate distance of the data from the SVM discriminating hyperplane (projection values, i.e., the decision value given by its position relative to the classification boundary), which is used to inform participants about their own performance.