I’m glad that there’s some more modern research around this general idea. Of course the reliance of humans on the power of visual memory goes back to ancient Greece with the method of loci and from the Renaissance (or earlier) with the mnemonic major system.
I know both systems intimately well since the age of about 11, though I haven’t written much about them on my site. (I should fix this, though there are some related tangents within my memory category.) I did notice a large overlap with the major system and Gregg shorthand a while back, which leads me to believe that they’ve got an even richer back history than most may presume.
I’ve always been confounded that these systems aren’t better known in modern culture, though some sources have indicated that religious influences tamped down their proliferation in the 1500’s.