When does length cause the word length effect?

Jalbert, Annie (2011) When does length cause the word length effect? Doctoral (PhD) thesis, Memorial University of Newfoundland.

[English] PDF - Accepted Version Available under License - The author retains copyright ownership and moral rights in this thesis. Neither the thesis nor substantial extracts from it may be printed or otherwise reproduced without the author's permission. Download (15MB)

Abstract

The word length effect - the finding that lists of short words are better recalled than lists of long words - has been termed one of the benchmark findings that any theory of immediate memory must address. The effect is viewed as the best remaining evidence for time-based decay of information in short-term memory. However, previous studies investigating this effect have confounded word length with orthographic neighborhood size. I suggest here that the word length effect may be better explained by the differences in lexical properties of short and long words than by length. Experiments 1a and 1b revealed typical effects of length when short and long words were equated on all relevant dimensions except for neighborhood size. Experiments 2 and 3 showed that when short and long words were equated for neighborhood size, the word length effect disappeared. Experiment 4 replicated the disappearance of the word length effect with spoken recall. In Experiment 5, one-syllable words with a large neighborhood were recalled better than one-syllable words with a small neighborhood. Experiment 6 found that concurrent articulation removed the effect of neighborhood size, just as it removes the effect of word length. Experiment 7 demonstrated that this pattern is also found the nonwords. In Experiment 8, length and neighborhood size were manipulated and only effects of the latter were found. These results are problematic for any theory of memory that includes decay offset by rehearsal, but are consistent with accounts that include a redintegrative stage that is susceptible to disruption by noise. The results also confirm the importance of lexical and linguistic factors on memory tasks thought to tap short-term memory. These results add to the growing literature identifying problems for theories of memory that include decay offset by rehearsal as a central feature.

Actions (login required)

View Item