Effects of phonological and orthographic neighbourhood density interact in visual word recognition

Abstract

The present study investigated the role of phonological and orthographic neighbourhood density in visual word recognition. Three mechanisms were identified that predict distinct facilitatory or inhibitory effects of each variable. The lexical competition account predicts overall inhibitory effects of neighbourhood density. The global activation (familiarity) account predicts overall facilitatory effects of neighbourhood density. Finally, the cross-code consistency account predicts an interaction, with inhibition of phonological neighbours in sparse orthographic regions and facilitation of phonological neighbours in dense orthographic regions. In Experiment 1 (lexical decision), a cross-over interaction was indeed found, supporting the prediction of the cross-code consistency account. In Experiment 2, this cross-over interaction was exaggerated by adding pseudohomo-phone stimuli (e.g., brane) among the nonword targets. Finally, in Experiment 3 (progressive demasking), we tried to shift the balance between inhibitory and facilitatory mechanisms by using a perceptual identification task. As predicted, the inhibitory effects of phonological neighbourhood were amplified, whereas the facilitatory effects disappeared. We conclude that the level of compatibility across co-activated orthographic and phonological representations is a major causal factor underlying this pattern of effects.

Acknowledgments

The authors thank Jeff Bowers and Marcus Taft for their helpful comments on an earlier version of this work.

Notes

Although semantic representations are not shown in Figure 1, we hypothesize that these are activated via whole-word orthographic and phonological representations. The framework therefore provides a direct orthographic route to semantics and a phonologically mediated route (e.g., Taft & van Graan, 1998).

This can explain why Coltheart et al. (1977) actually failed to find an effect of neighbourhood density on word targets in the lexical decision task, since the stimuli they tested were relatively frequent words.

The stimuli are the same as those used in Experiment 1 of Ziegler et al. (2003) and can be found in the appendix of that article.