Reducing the burden of neurological disorders (e.g. epilepsy and Alzheimer’s) has become a top research priority. Insights into the basic mechanisms of brain function have enabled the discovery of key concepts regarding brain dysfunction, however, the understanding necessary for treatment and diagnosis is limited due to the complex interplay between ionic and bio-molecular communication in massively interconnected neural networks. The current state-of-the-art of implantable biomedical tools for probing brain function can only sense local electric field potentials, lack the ability to release drugs, and show poor biocompatibility leading to scarring of brain tissue. The goal of BiOprobe is to develop a new generation of chronically implantable probes with multi-sensing recording and chemical stimulation devices for local delivery of drugs that will drastically improve our ability to interface with the nervous system. To achieve these goals, we will utilize organic electronic materials and devices -- often targeted for their low cost processing, and chemical tunability of properties. Through their softness, flexibility and ion permeability, these materials create unique opportunities at the interface with biology that can help transcend the current state-of-the-art in transduction and stimulation of cell activity. Of particular interest to this interface are organic electrochemical transistors that have recently been demonstrated as sensitive biosensors for metabolites such as glucose, and organic electronic ion pumps capable of delivering biochemical stimuli to neurons with precise spatial and temporal control. Using these advances, BiOprobe will deliver a biomedical research tool capable of multifunctional recording and stimulation in a format that is necessary for chronic implantation in animals. This tool will have a major impact on neuroscience research on the origins of cognitive deficits and other aspects of neuronal activity/function in vivo.