Figure 4: Mapping EEG-EMG coherence based on significant coherence values of the selected 128 EEG channels with EMG of the three muscles at the beta (15-35 Hz) band in CRF patients (left two columns) and healthy subjects (right two columns). The color bar indicates -transformed coherence values (red means higher and blue lower coherence). The level of coherence declined substantially in stage 2 (fatigue condition, 2nd, and 4th columns) compared with stage 1 (1st and 3rd columns). The coherence values in CRF patients were remarkably lower compared to those in the controls especially in stage 1. BB: biceps brachii; BR: brachioradialis; TB: triceps brachii; P: patients; C: controls.