This is an incredibly unfair request if you aren’t incredibly familiar with the film, but I figured I’d try anyways.
There is a film I am looking for, but the only thing I can remember right now is one scene. I will try to be as detailed as possible, and if you decide to humor my request and need more info, I will do my best.
There is a man that is in an isolation tank, elevated 3 or 4 feet, in a laboratory. He is screaming. Outside the tank, is a scientist and a man wearing a wristwatch talking. As they leave, the man screaming ends up with the wrist watch (brown leather strap, golden colored watch). The isolation tank kind of looks like a fish tank. There isn’t room to fully stand and there is a white mini-mattress beneath the man. I got the indication from the scene that the man in the tank was of college age, and signed up for the experiment for money or college credit. There is a shot of the man’s bear wrist, then a clock in the lab, and then the man explains that the screaming man just needed to be aware of time.
I believe the scene establishes that time and awareness play into the plot, and that the man who slipped his wrist watch into the tank is intelligent and compassionate. You never actually see the man slip the watch into the tank. One minute he has the watch. The next minute the screaming man quietly clutches the watch, the show a shot of the watch owner’s bare wrist, a clock in the lab, and then the man gives his explanation.
I believe this movie came out in the late 1990’s or early 2000’s. 