Semantic richness, concreteness, and object domain: an electrophysiological study

Area of Science:

• Cognitive Neuroscience
• Psycholinguistics

Background:

• Previous event-related potential (ERP) studies on semantic richness and concreteness effects yielded inconsistent results.
• Semantic richness is often measured by the number of features (NOF) for a concept.
• Object domain has been shown to influence ERP amplitude and topography.

Purpose of the Study:

• To investigate the effects of semantic richness (NOF) and concept concreteness on ERPs and behavioral decision latencies.
• To examine the influence of object domain (animals vs. nonliving things) on these effects.
• To reconcile mixed findings in prior ERP research on semantic processing.

Main Methods:

• Participants performed a concrete/abstract decision task.
• Event-related potentials (ERPs) and behavioral decision latencies were recorded.
• High and low NOF concepts from animal and nonliving thing categories were used, matched for confounds.

Main Results:

• Behavioral decision latencies supported a semantic richness continuum.
• Electrophysiological activity (ERPs) did not fully support this continuum.
• Concrete concepts elicited larger negativities than abstract concepts.
• Low NOF concepts elicited larger negativities than high NOF concepts.
• An increased posterior positivity was observed for animal concepts.
• The NOF effect was larger for animal concepts than for nonliving things.

Conclusions:

• While behavioral responses align with a semantic richness continuum, ERPs present a more complex picture.
• Concreteness and semantic richness (NOF) modulate neural processing, with distinct effects observed.
• Object domain interacts with semantic richness, suggesting domain-specific processing differences.