“…Therefore, if one took the wider stimulus set, 5-min delay surface and expanded stimulus relatedness into domains beyond words, RI may decrease again, producing a nonlinear effect reminiscent of those found across early studies employing a wide variety of stimulus types, including with numbers, number-letter combinations, nonsense syllables, abstract visual symbols, poetry, and prose ( Britt, 1935 ; Robinson, 1927 ; Gibson, 1941 ; Parducci and Knopf, 1958 ; Cheng, 1929 ; Lund, 1926 ; Dreis, 1933 ; Harden, 2010 ; Gibson and Gibson, 1934 ; Rothkopf, 1957 ). Additionally, future studies could explore how surfaces differ based on less nameable stimuli types, such as stimulus spaces with continuous, quantifiable changes in visual stimuli (e.g., Wammes et al, 2021 ; Molitor et al, 2021 ; Iordan et al, 2020 ; Natu et al, 2016 ), or other domains ( Dennis, 1976 ).…”