Simultaneous Neural and EMG Recording Protocols

Neural activity was recorded simultaneously in both IOS and 2PLSM as the differential potentials between the two leads of either the PFA-coated tungsten microwires (#795500, A-M Systems, Sequim, WA) (Huo et al., 2014 (link); Winder et al., 2017 (link)) for cortical and hippocampal stereotrodes. EMG activity was identically recorded with PFA-coated 7-strand stainless-steel microwires (#793200, A-M systems, Sequim, WA). Stereotrode tungsten microwires were threaded through polyimide tubing (#822200, A-M Systems, Sequim, WA) giving an interelectrode spacing of ~100 µm. The tungsten microwires were crimped to gold pin connectors, with impedances typically between 70 and 120 kΩ at 1 kHz. EMG stainless-steel microwires were fabricated in a similar fashion, but with an interelectrode spacing of several mm. Each signal was amplified and hardware bandpass filtered between 0.1 Hz and 10 kHz (DAM80, World Precision Instruments, Sarasota, FL) and then digitized at 20 kHz (PCIe-6341 for IOS experiments, PCIe-6321 and PCIe-6353 for 2PLSM experiments, National Instruments, Austin, TX).