Simstim is - at least in part - being worked on by a company called Openwater[0]. Mary Lou Jepsen did a talk at the Long Now Foundation a while back that speaks to the ambition of thought/memory recording via an MRI-like device and the "insertion"/playback of the same in other people [1].
[0]www.openwater.cc [1]www.longnow.org/seminars/02018/oct/29/toward-practical-telepathy/