This channel has lots of content on this topic. Including interviews with all the top people. https://www.youtube.com/c/CloserToTruthTV/videos To me it seems like consciousness can only be passed from one being to another. And since we are all just a collection of cells, and everything that we are is coded inside a cell. It seems to me that consciousness must exist at the cellular level.
Is there a reason you think consciousness can't simply be explained as brain activity?
1) Your brain cells are just a special type of cell. How these brain cells send and receive signals, interact and make connection, is coded at the cellular level. Software without hardware to run on, is just text.
2) You are born with certain conscious behaviours that you don't need to learn. This behaviour must be passed between generations using DNA/RNA. Therefore the coding for that later behaviour must already be present when you were just two cells.