Plug Removal for acute in vivo Electrophysiology Experiments v1

This protocol describes the procedure for removing the SORTA-clear plug used in acute in vivo electrophysiology experiments in whole-hemisphere craniotomy (WHC) preparation mice with Neuropixels probes. This exact methodology is crucial to these experiments due to the role the SORTA-clear plug plays in preserving the brain prior to the described procedure. After the mice undergo a WHC surgery, the implant used to replace the skull on the left hemisphere is covered with a SORTA-clear plug, which keeps the brain from potentially interacting with air or debris, as the SORTA-clear seals the holes in the implant and thus ensures the brain stays healthy between surgery recovery, training, and subsequent experiments. However, we cannot insert Neuropixels probes through SORTA-clear, meaning we must remove it before the experiment. After the SORTA-clear is removed, we place another temporary seal over the brain - Kwik-Cast. This is a more temporary measure and acts as another easily removable seal to preserve the brain just prior to recording. We recommend doing this procedure 1 day prior to the procedure outlined in Neuropixels Data Collection: Whole Hemisphere Recordings as to not expose the mouse to anesthesia on the day of recording, but if necessary, this procedure can be done on the same day as a recording as long as the mouse is given two hours to recover from the anesthesia.