Abstract: Obesity and other medical conditions can be managed using a closed-loop system, which uses one or more implantable recording electrodes, a processing device, and one or more implantable stimulating electrodes. The one or more implantable recording electrodes can record signals from a portion of one or more subdiaphragmatic branches of a patient’s vagus nerve. The processing device can be configured to: receive the signals from the portion of the one or more subdiaphragmatic branches of the patient’s vagus nerve, perform signal processing to decode the signals from the portion of the one or more subdiaphragmatic branches of the patient’s vagus nerve, and configure a stimulation to decrease the patient’s hunger and/or increase the patient’s satiety based on the decoded signals. The one or more implantable stimulating electrodes can deliver the configured stimulation to another portion of one or more subdiaphragmatic branches of the patient’s vagus nerve.