Sometimes, it is necessary to re-learn a previously learned movement behavior, for example, a bad posture during the golf drive or while playing the piano. Unlearning or relearning an intensively trained behavior is particularly important if the behavior is hampering recovery, for example, in chronic pain or after a stroke. With this pilot study, the brain mechanisms that control the change of pre-existing stable memories of a motor skill will be tested with electroencephalography (EEG). Non-invasive brain stimulation will be used to modulate these brain mechanisms and test if it is possible to change the pre-existing motor memory and the learning of a new motor skill.