LEDs use pulse width modulation to dim, so if it's a subpar circuit with relatively large width duty cycle, that might be what you're picking up. Might want to

LEDs use pulse width modulation to dim, so if it's a subpar circuit with relatively large width duty cycle, that might be what you're picking up. Might want to check out persistence of vision displays. They rely on tricking your brain in similar ways. Do florescent lights bother you too at all? Also from what I've heard sometimes people will only see visuals after a second time taking LSD or by taking a more substantial sized dose.