Word Length Effect

The word length effect is the finding that, on tests of immediate serial recall that measure short-term or working memory span, people can typically remember and correctly reproduce a shorter list made up of long words, such as multi-syllable words, than an equally long list made up of short, one-syllable words, even when the words are matched for factors such as how common or familiar they are. The effect is explained within Alan Baddeley and Graham Hitch's influential working memory model by the operation of a component called the phonological loop, which is understood to maintain verbal information through continuous, rapid subvocal rehearsal, essentially silently repeating the items to oneself; because longer words simply take more time to say and rehearse than shorter ones, fewer of them can be cycled through this rehearsal process within the brief window before earlier items begin to fade from memory. Researchers have found that measured memory span for a given category of words correlates closely with how quickly people can actually speak those words aloud, providing strong converging support for a time-based, rehearsal-dependent account of the effect rather than one based simply on the number of separate items to be remembered. Alongside the phonological similarity effect documented elsewhere in this section, the word length effect is considered one of the two central pieces of behavioral evidence supporting the existence of a distinct, capacity-limited phonological loop within human working memory.