I've tried this for an extended period of time and it hasn't yielded a huge improvement. When I'm laying in bed at night, close to falling asleep, if I concent

I've tried this for an extended period of time and it hasn't yielded a huge improvement. When I'm laying in bed at night, close to falling asleep, if I concentrate really hard, I can sometimes get a little glimpse of mental imagery. Like a fleeting moment (perhaps ~500ms) of seeing a full scene (a forest, mountains, a city) but then it's gone. I think a mistake people make is trying to "see" things in the blackness of their eyes. I've noticed when I get these fleeting images it's when I'm kind of not "looking" at the black, but kind of relaxing my eyes on turning off my attention to my "photon-based" visual system.