Fig. 4

Example of the one-stroke patient’s brain activation in different experimental conditions from group 2 with a relatively better hand function which had a left brain injury. A, B Time–frequency graph of ERSP values in grasp tasks of C3/C4 channels; C, D Time–frequency graph of ERSP values in open tasks of C3/C4 channels. At 0 s, the voice instruction prompts the patient to prepare for the motor task, and at 3–5 s, the patient is performing the motor task