Symbolism itself does not improve memory for elements on the periodic table

Recent work demonstrates that symbols (e.g., $) are reliably better remembered than their word counterparts (e.g., 'dollar'). It remains an open question whether the memory benefit observed for symbols is due to their unique visual form, or because they offer a symbolic representation of to-be-remembered information. Here, we assessed memory for symbols on the periodic table of elements, which could be presented in symbol format (e.g., H) or word format (e.g., Hydrogen), and compared both to memory for meaningless letters (e.g., J). These stimuli were selected because they all share the same visual features and the former two share the same meaning. Memory was compared across individuals with and without a background in chemistry. In non-experts, memory was highest for words relative to symbols and meaningless letters. In experts (students who had passed an introductory chemistry course), however, memory for words and symbols was equivalent, with both higher than for meaningless letters. Results suggest that prior knowledge of what a symbol means is necessary to gain a memory benefit over semantically-void information, but is not enough to boost memory relative to words. We suggest that using a concrete visual symbol to represent an abstract concept is not enough to confer a memory advantage relative to words; a meaningful and visually distinctive symbol may be necessary.