Stem Formation in French Verbs: Structure, Rules, and Allomorphy

Stem processing is an essential phase in word recognition. Most modern Romance languages, such as Catalan, Italian, Portuguese, Romanian, and Spanish, have three theme vowels that define verbal classes and stem formation. However, French verbal classes are not traditionally described in terms of theme vowels. In this work, stem formation from theme vowel and allomorphic processes was investigated in French verbs. Our aim was to define the verbal stem formation structure processed during mental lexicon access in French. We conducted a cross-modal experiment and a masked priming experiment on different French stem formation processes from the first and third classes. We compared morphology-related priming effects to full priming obtained through identity priming, as well as to no priming obtained through a control condition. Stems from the first and third classes with a theme vowel presented full priming, whereas stems from the third class with allomorphy presented partial priming in both experiments. Our results suggest root-based stem formation for French. Verbs are recognized through word decomposition into stem and inflectional suffixes, and stem processing is based on root, theme vowel, and allomorphic processes. These results support a single-mechanism model with full decomposition and pre-lexical access defined by morphological rules.