Unmasking the Effects of Orthography, Semantics, and Phonology on 2AFC Visual Word Perceptual Identification

Abstract

In the two-alternative forced-choice (2AFC) task, the target stimulus is presented very briefly, and the participants must choose between two options as to which was the presented target. Some past research (Grossi et al., 2009; Haro et al., 2019) has assumed that the 2AFC word identification task isolates orthographic effects, despite orthographic, semantic, and phonological differences between the alternative options. If so, performance should not differ between word target/nonword foil pairs and British/American word pairs, the latter of which only differ orthographically. In Experiment 1, accuracy and sensitivity were higher during word/nonword trials than British/American trials when participants stated their response was not a guess, demonstrating that phonological/semantic processing contributes to 2AFC performance. In Experiment 2, target visibility was manipulated by increasing the contrast between target and mask for half the trials. Experiment 2 showed that target visibility did not interact with pair type on reaction time, which suggests phonological/semantic processing did not result in feedback to orthographic encoding in this task. This study demonstrates the influence of phonological/semantic processing on word perceptual identification, and shows that 2AFC word identification does not isolate orthographic effects when word/nonword pairs are used, but using British/American word pairs provides a method for doing so. Implications for models and future research are discussed.