Brain-computer interfaces (BCIs), when used for medical application, allow patients suffering from severely debilitating diseases to improve their life quality. A BCI translates brain signals in commands that can be used by the patient to drive several instruments, without the need of an electromyography (EMG) that is instead necessary in applications like myoelectric prosthesis. In fact, the BCI approach grants the possibility to interact with the external environment also to patients suffering from severe neuromuscular diseases, such as locked-in syndrome or advanced stages of multiple sclerosis. Currently, the most widespread technique used to monitor the brain signals in a BCI pipeline is electroencephalography (EEG), where a set of electrodes placed on the subject’s head measures the potential differences related to neural activity.