Are lexical decisions a good measure of lexical access? The role of word frequency in the neglected decision stage.

TLDR

The study proposes a simple two‑stage model to explain how word frequency and other lexical variables influence lexical decision performance. Three experiments manipulated five lexical variables across category verification, lexical decision, and pronunciation tasks, and the authors applied the two‑stage model to analyze the resulting reaction‑time data. The results revealed that word‑frequency effects vary by task—minimal in category verification, moderate in pronunciation, and pronounced in lexical decision—suggesting that decision processes unrelated to lexical access amplify the frequency effect and casting doubt on using lexical‑decision data to test lexical‑access assumptions.

Abstract

Three experiments investigated the impact of five lexical variables (instance dominance, category dominance, word frequency, word length in letters, and word length in syllables) on performance in three different tasks involving word recognition: category verification, lexical decision, and pronunciation. Although the same set of words was used in each task, the relationship of the lexical variables to reaction time varied significantly with the task within which the words were embedded. In particular, the effect of word frequency was minimal in the category verification task, whereas it was significantly larger in the pronunciation task and significantly larger yet in the lexical decision task. It is argued that decision processes having little to do with lexical access accentuate the word-frequency effect in the lexical decision task and that results from this task have questionable value in testing the assumption that word frequency orders the lexicon, thereby affecting time to access the mental lexicon. A simple two-stage model is outlined to account for the role of word frequency and other variables in lexical decision. The model is applied to the results of the reported experiments and some of the most important findings in other studies of lexical decision and pronunciation.