A Fine-Grained Investigation of Single-Trial N400 Amplitudes and Response Times in Association- and Similarity-Driven Abstract and Concrete Word Priming

Research investigating two-way interaction effects of concreteness, priming and/or the type of prime-target relation helped us understand the mechanisms involved in contextual semantic processing while yielding partially conflicting findings. We investigated the interplay of all three factors in a priming paradigm manipulating target concreteness, prime semantic diversity and prime-target similarity-/association-based relation-strength, measuring N400 amplitudes and lexical decision times in 40 and 70 participants, respectively. The single-trial N400 analysis confirmed that processing abstract words was more strongly modulated by relation-strength than concrete words. Unexpectedly, a prime’s high vs. low semantic diversity partially reversed similarity-driven N400 modulations, irrespective of concreteness. Regarding reaction times, semantic diversity reduced whereas relation-strength enhanced priming effects, unexpectedly irrespective of concreteness. Our results support semantic control hypotheses and controvert differential representational frameworks for concrete and abstract words. Additionally, a primes’ semantic diversity seems to directly affect whether the prime-target relation strength reduces semantic retrieval effort and eventually facilitates semantic word processing.