Linking learning-specific event-related potential changes to individual success in novel word acquisition

To determine whether learning-specific event-related potential (ERP) changes are related to individual success in novel word acquisition, using a pre-post design that accounts for pre-existing differences between novel and familiar words.

Thirty-four healthy adult native Russian speakers learned 20 novel pseudowords embedded in sentences, with 20 familiar words as controls. ERPs were recorded before and after learning. Acquisition of the novel words was assessed with four tasks targeting form and meaning retrieval: free recall and recognition of word forms, and free definition and semantic judgment of word meanings. The learning-specific ERP index was calculated as the difference in pre-post ERP changes between novel and familiar words. Pearson correlations between this index and behavioral measures of learning success were assessed using cluster-based permutation analysis across 0-900 ms.

Learning-related ERP changes were significantly associated with free recall and recognition accuracy. Free recall showed a positive correlation cluster from 486 to 900 ms, corresponding predominantly to P600-like activity. Recognition showed a positive cluster from 312 to 900 ms, spanning N400- and P600-like periods: higher recognition accuracy was associated with greater N400 attenuation and P600 enhancement. Both effects showed widespread frontal, central, and parietal distributions. No significant associations were found for definition or semantic judgment.

Our approach provides a more specific measure of learning-related neural change. These findings demonstrate the behavioral relevance of learning-related ERP changes and support a distributed spatiotemporal neural signature of successful novel word acquisition.