Individual-Level Prediction of Exposure Therapy Outcome Using Structural and Functional MRI Data in Spider Phobia: A Machine-Learning Study

Figure 3

The Shapley (SHAP) values and feature importance of the 1st-level variance classifier in the responder () vs. nonresponder () prediction using functional features across ROIs covering the whole brain. Positive SHAP values indicate a contribution of feature value in favour of the positive class prediction (future responder); negative Shapley values are in favour of the negative class prediction (future nonresponder). Larger absolute Shapley values indicate a larger impact on the model output. The 20 most contributing features are shown and ranked in decreasing order of mean absolute SHAP value. Horizontal violin plots on the left represent the distribution of all individuals in the test set across all cross-validation iterations. For each feature, relative values are represented on the left by a color gradient.