Fig. 1: Schematic of FIMOSS for long-term function evaluation of peripheral nerve plexus.

a The FIMOSS implant, which was comprised of multiple μLEDs to realize multisite neuromodulation, was designed for optogenetic stimulation of peripheral plexus in mice, such as brachial plexus. b Diagram of the layout of the cuff optrode (MOSD II) surrounding along the length of peripheral nerve. A μLED activates a single nerve fascicle with sub-activation resolution. c When applied on the brachial plexus, the main body of the FIMOSS implant was fixed on the surface of the pectoralis major, while MOSD II and the interconnect interfaced with the brachial plexus through an incision of the pectoralis major. d MOSD II has 4 μLEDs on the flexible substrate, which can wrap around the nerve trunk of the brachial plexus (middle trunk as an example) and stimulate the nerve with sub-nerve resolution. e Distinct forelimb muscle groups activated by different μLEDs of FIMOSS implants. Contraction of muscles, including biceps brachii, triceps brachii, forearm extensors and flexors can be induced, respectively. Biceps brachii, red. Triceps brachii, yellow. Forearm extensors, green. Forearm flexors, blue.