Subliminal syntactic priming.

Subliminally presented words have been shown to cause priming at orthographic and semantic levels. Here, we investigate whether subliminal priming can also occur at the syntactic level, and use such priming as a tool to probe the architecture for processing the syntactic features of written words. We studied the impact of masked and unmasked written word primes on response times to a subsequent visible target that shared or did not share syntactic features such as grammatical category and grammatical number. Methodological precautions included the use of distinct lists of subliminal primes that were never consciously seen, and the verification that participants were at chance in a prime-classification task. Across five experiments, subliminal priming could be induced by the repetition of the same grammatical category (e.g. a noun followed by another noun), by the transition between two categories (e.g. a determiner followed by a noun), or by the repetition of a single grammatical feature, even if syntax is violated (e.g. "they lemons", where the expression is ungrammatical but the plural feature is repeated). The orthographic endings of prime words also provided unconscious cues to their grammatical category. Those results indicate the existence of a representation of abstract syntactic features, shared between several categories of words, and which is quickly and unconsciously extracted from a flashed visual word.