I highly suggest you read Norbert Wiener’s 1948 book titled “Cybernetics” and especially chapter 4 “Feedback and Oscillation.” chapter 5 “Computing Machines and the Nervous System” and chapter 9 “On learning and self reproducing machines”

If you want to really delve even deeper (since you are a phd), I highly suggest you also pick up a copy of the Macy conferences (https://www.wikiwand.com/en/Macy_conferences#/Cybernetics_Conferences) transcripts.