The fundamental role of position in affix identity

Previous research suggests that while free morpheme identification during visual word recognition is position-independent, suffixes are activated only when they occur after the stem. Surprisingly, prefix position coding has not yet been assessed. This point is important given that some experimental studies demonstrated clear processing differences between prefixes and suffixes. In this study we examined whether Spanish suffixes and prefixes are recognized independently of their position by adapting the Crepaldi, Rastle, and Davis’s (2010) experimental paradigm. We observed that morphologically structured nonwords in which the affix occurs in its typical position (e.g., curiosura, disgrave) are rejected more slowly and less accurately than their matched orthographic controls (e.g., curiosula, dusgrave). Crucially, such morpheme interference effect is completely absent when the morphemes are inverted (i.e., uracurios and gravedis are rejected as easily as ulacurios and gravedus). Our data provide strong support to the hypothesis that all affix processing is sensitive to position.