Word length vs. lexical factors: Re-examining what causes the word-length effect in serial recognition

The word-length effect refers to the finding that memory on many short-term/working memory tasks is better for words with fewer syllables than words with more syllables. The standard account attributes this result to a combination of decay offset by rehearsal: More short words can be rehearsed because they take less time to articulate. However, most studies have confounded length with lexical and other long-term memory factors that covary with length. In this paper, we reexamine word-length effects in serial recognition. Experiment 1 replicated previous findings of a word-length effect when short and long words also differed on numerous other dimensions. Experiment 2 found that when the short and long words were more fully equated, including being equated for orthographic and phonological neighborhood size, the word-length effect disappeared. Experiment 3 confirmed that memory was better for words with more orthographic and phonological neighbors than words with fewer neighbors, showing serial recognition is sensitive to at least some lexical/long-term memory factors. The results provide more evidence against the standard account of the word-length effect and instead are consistent with a growing body of work which shows that lexical and other long-term memory factors affect performance in short-term/working memory tasks.