Do a search for “subliminal messaging” - this was something that became quite the topic in prior era; there was legislation passed back in 60’s/70’s after they did blatant things like embedding photos of cold soda or popcorn into movies. It extends further such as drawing thing into other pictures; at the time ice cubes drawn into advertising were always a source of controversy for example. These particular videos are interesting because they have a bunch of graphics that clearly have other images embedded in them - like dot papers - but it’s impossible to make out fully. The thesis is that the human mind and its sensory mechanisms - sight, smell, touch, etc. can interpret things at light speed - we can decipher such things mentally even though we don’t fully see them, albeit embedded into pictures such as dots or a frame in a picture. These apparent MkUltra videos do both and have obnoxious sounds in their video treks - clearly for mind altering experiences. The results of such things are brainwashed people like the Hoggster or the shooter Cruz or the suicide at WH yesterday IMO.
The images were thought invoking, but had they been subliminal you’d not be discussing them, having not consciously seen them. Here’s the book that started it all ...
https://www.amazon.com/Hidden-Persuaders-Vance-Packard/dp/097884310X