Abstract: This application is directed to a neuromodulation system applying a closed-loop neural recording and stimulation process to treat cognitive or neurological dysfunctions. The neuromodulation system includes one or more electrode arrays implanted in a brain region of a patient, an implantable electronics package mounted on a skull under the scalp, and an external electronic system wearable by the patient. A plurality of channels are provided by a plurality of electrodes of the electrode arrays. Local field potential (LFP) recordings are collected from the brain region of the patient via the channels provided by the electrode arrays. The electronics package generates a spectral decomposition of the LFP recordings, updates a cognitive computational model, and delivers stimulation to the brain region of the patient via at least a subset of electrode arrays based on the cognitive computational model. The external electronic system enable at least wireless data communication with the electronics package.