Enabling closed-loop neurostimulation research with downloadable firmware upgrades

We present a simulated case study using investigational, downloadable firmware updates to configure an existing implanted deep brain stimulator. With the upgrade, closed-loop algorithm parameters affecting stimulation state classification and stimulation timing can be embedded within the device to allow for chronic investigation of closed-loop concepts both flexibly and incrementally. The system can be outfitted with either cortical sensing electrodes or depth electrodes to explore a variety of closed-loop paradigms. The prototype case study presented here uses motor intention signals to titrate stimulation, a relevant use case for treatment of movement disorders, though the technology is extensible to other neurological disorders. To highlight the translational capabilities of this tool, the key technology considerations of battery power usage, chronic sensitivity and stability of biomarkers, and parameter tuning are discussed using representative testing and data sources.