Simultaneous high-density 512-channel SiNAPS electrical recordings and optogenetics.

The experimental use of CMOS high-density neural probes enables the wide field observation of the electrical activity of neural circuits at the resolution of single neurons. Optogenetic light stimulation allows to control and modulate the activity of neural cells, in a genetically selective manner. The combination of these techniques can be a powerful approach for investigating mechanisms of brain diseases and of information processing in the brain.

Force Measurements to Advance the Design and Implantation of CMOS-based Neural Probes.

Objective: Tissue penetrating active neural probes provide large and densely packed microelectrode arrays for the fine-grained investigation of brain circuits and for advancing brain-machine interfaces (BMIs). To improve the electrical interfacing performances of such stiff silicon devices, which typically elicit a vigorous foreign body reaction (FBR), here we perform insertion force measurements and derive probe layout and implantation procedure optimizations.

Methods: We performed in-vivo insertion force measurements to evaluate the impact of probe design and implantation speed on mechanically induced trauma and iatrogenic injury.

Advancing the interfacing performances of chronically implantable neural probes in the era of CMOS neuroelectronics.

Tissue penetrating microelectrode neural probes can record electrophysiological brain signals at resolutions down to single neurons, making them invaluable tools for neuroscience research and Brain-Computer-Interfaces (BCIs). The known gradual decrease of their electrical interfacing performances in chronic settings, however, remains a major challenge. A key factor leading to such decay is Foreign Body Reaction (FBR), which is the cascade of biological responses that occurs in the brain in the presence of a tissue damaging artificial device.