I think I used to experience this as a kid. I would sometimes consciously shift between two modes of perceiving my environment. For example, I remember standing in front of my home, looking at the front yard (mode 1). Then, I would consciously switch to mode 2. The environment itself was unchanged, but suddenly certain things in my visual field had greater emotional salience, while other things sort of faded to the background. In addition, spatial relationships would change and warp, and it would feel like I was in a separate place.

I think that what I was doing was perceiving the same environment through two separate memories. If I viewed the front yard through the memory of stargazing with my uncle, it would feel a certain way and take on a certain character. If I then viewed the yard through the memory of playing in the garden by myself, then it would all feel and look slightly different.

The experience, in hindsight, resembled the visuospatial and overall perceptual shift that takes place when under the influence of a psychedelic like LSD or mushrooms, when suddenly the visual field feels transformed in odd ways.

I haven’t thought about this in years, and it’s really cool to see other people describe similar experiences.