An intrafascicular electrode with integrated amplifiers for peripheral nerve recording

Thin-film longitudinal intrafascicular electrodes (tf-LIFE) are widely used for peripheral nerve recordings. tf-LIFEs are also promising electrodes for neural signal acquisition in future peripheral nerve prostheses. However, common mode signal interference, and electrical artifacts originating from long wire leads and wire movement are known problems encountered when using such electrodes, which lead to degradation in the recording quality. Here, we report an active tf-LIFE electrode implemented by integrating a neural amplifier chip die in close proximity to a tf-LIFE electrode. Consuming only 1mW and measuring 37 mm×7.2 mm×2.4 mm, this active tf-LIFE electrode creates a reliable connection and considerably shortens the distance between the electrode site and neural amplifier. This active electrode has demonstrated repeatable in-vivo recordings of compound action potentials from the rat sciatic nerve. Our results show that this electrode is suitable for repeated in-vivo recordings of compound action potentials from nerves in applications such as peripheral and visceral nerve interfaces that require low-noise stable nerve recordings.