If you work in AAC, you’ve encountered the AAC symbol hierarchy. You know—the idea that some symbols, like photographs, may be easier for kids to learn because they are more iconic. There’s a lot of chatter out there about this concept. Does a hierarchy exist? Is it just a myth? Guess what—the answer’s not so straightforward.
In this study, 13 school-aged students with both developmental and language delays participated in an observational symbol-learning task on the computer. They were shown 6 “iconic” Blissymbols and 6 “arbitrary” lexigrams. The Blissymbols looked like their referents (the one for clock looked like a clock), while the lexigrams had no relationship to their referents.
The task was simple: the students touched the symbols on the screen and a color photograph of the corresponding vocabulary popped up. The students did this repeatedly for 30 minutes, for a maximum of 12 sessions, and were then tested for their symbol-learning.
Turns out there was a very small advantage for the iconic symbols (they learned one more symbol), but only when the students knew the vocabulary beforehand. So if a student knew the concept DOG, they were a bit more likely to learn the iconic symbol for DOG, rather than the arbitrary symbol.
But, what if students didn’t know the vocabulary (an oh-so-common occurrence)? There was no difference in the students’ ability to learn an iconic symbol versus an arbitrary symbol, when the vocabulary was previously unknown. So if a student didn’t know the concept GORILLA, they were just as likely to learn the iconic symbol as the arbitrary symbol.
This is not a black-and-white situation! Yes, iconic symbols may have a slight advantage in some situations. But—if you’re teaching new vocabulary, it’s probably not worth getting hung up on iconicity, since how closely a symbol looks like its referent doesn’t seem to make or break the learning process.
Sevcik, R. A., Barton-Hulsey, A., Romski, M., & Hyatt Fonseca, A. (2018). Visual-graphic symbol acquisition in school age children with developmental and language delays. Augmentative and Alternative Communication, 34(4), 265–275.