Brain stimulation system, comprising: at least one implantable sensor device which is adapted for being placed into a brain cavity of a patient, and for sensing neuronal signals of the patient, at least one neuronal stimulation device which is adapted for being placed into the brain cavity, and for applying stimulation signals to the patient, an implant control unit which is implantanble into the patient's body and connectable with the at least one neuronal sensor device and the at least one neuronal stimulation device, and which is adapted for receiving the sensed neuronal signals from the at least one sensor device, and for generating the stimulation signals and applying the stimulation signals to the at least one stimulation device on the basis of control signals, and which comprises means for continuously sending and receiving signals via a wireless data link, a body-external, portable processing device which is adapted for being worn by the patient and for being coupled with the implant control unit via the wireless data link, the portable processing unit being further adapted for receiving signals from the implant control unit, for storing the received signals, and for generating the control signals based on the signals received from the implant control unit, and for sending the generated control signals via the wireless data link, to the implant control unit, wherein the implant control unit is implantable into the patient's body, and characterized in that the body-external, portable processing device is adapted for continuously receiving and evaluating the sensor signals, and continuously generating and continuously feeding back the control signals to the stimulation device. at least one implantable sensor device which is adapted for being placed into a brain cavity of a patient, and for sensing neuronal signals of the patient, at least one neuronal stimulation device which is adapted for being placed into the brain cavity, and for applying stimulation signals to the patient, an implant control unit which is implantanble into the patient's body and connectable with the at least one neuronal sensor device and the at least one neuronal stimulation device, and which is adapted for receiving the sensed neuronal signals from the at least one sensor device, and for generating the stimulation signals and applying the stimulation signals to the at least one stimulation device on the basis of control signals, and which comprises means for continuously sending and receiving signals via a wireless data link, a body-external, portable processing device which is adapted for being worn by the patient and for being coupled with the implant control unit via the wireless data link, the portable processing unit being further adapted for receiving signals from the implant control unit, for storing the received signals, and for generating the control signals based on the signals received from the implant control unit, and for sending the generated control signals via the wireless data link, to the implant control unit, wherein the implant control unit is implantable into the patient's body, and characterized in that the body-external, portable processing device is adapted for continuously receiving and evaluating the sensor signals, and continuously generating and continuously feeding back the control signals to the stimulation device.