[geoelectric]

Look up "aphantasia". It's a relatively new (and trendy) term referring to an inability to "see" things in your mind. Apparently, most people can engage the visual cortex and actually form mental images, though I haven't really experienced this myself. I just get brief flashes, but mostly remember things factually.

I've personally found memory palaces and whatnot to be largely useless, probably because I can't visualize anything. Soundalike-based mnemonics work better for me (cockney rhyming slang type stuff, etc.)