Compound headedness in the mental lexicon: An event-related potential study

Compound words in Romance languages may have the head either in the initial or in the final position. In the present event-related potential (ERP) study, we address the hypothesis that Italian compounds are processed differently according to their head position and that this is mostly due to the perceived change in the canonical order of syntactic elements. Compound stimuli (head-initial, head-final, or exocentric) were visually displayed in two presentation modes, as whole words or separated into their constituents, in the context of a lexical decision task. Behavioural results showed an increased split cost in head-final and exocentric compounds as compared to head-initial compounds. ERP results showed an enhanced left anterior negativity (LAN) for head-final and exocentric compounds as compared to head-initial compounds, regardless of the presentation mode. Results suggest that the analogy with syntactic order may influence the internal structure of a compound and, as a consequence, its processing, but other characteristics (such as the grammatical properties of constituents) may affect the processing itself.