How the mass counts: An electrophysiological approach to the processing oflexical features

Nouns may refer to countable objects such as tables, or to mass entities su ch as rice. The mass/count distinction has been discussed in terms of both semantic and syntactic features encoded in the mental lexicon. Here we show that event-related potentials (ERPs) can reflect the processing of such le xical features, even in the absence of any feature-related violations. We d emonstrate that count (vs mass) nouns elicit a frontal negativity which is independent of the N400 marker for conceptual-semantic processing, but rese mbles anterior negativities related to grammatical processing This finding suggests that the brain differentiates between count and mass nouns primari ly on a syntactic basis. NeuroReport 12:999-1005 (C) 2001 Lippincott Willia ms & Wilkins.