TEMPORAL DYNAMICS OF LINGUISTIC AND VISUAL ACTIVATION DURING WORD PROCESSING: AN EEG-RSA STUDY

Understanding how conceptual knowledge is represented and accessed remains a central challenge in cognitive science. Contemporary theories increasingly propose that conceptual representations emerge from the interaction of multiple sources of information, including linguistic and perceptual experience. However, the temporal dynamics through which these representational sources contribute to semantic processing remain poorly understood. The present study investigated the temporal contributions of linguistic and visual information during word processing using electroencephalography (EEG) and time-resolved Representational Similarity Analysis (RSA). Fifty native Italian speakers completed a Deese-Roediger McDermott (DRM) paradigm while EEG activity was recorded. The present analysis focused on the encoding phase of the word condition. Neural similarity patterns derived from EEG activity were compared with linguistic and visual representational models to examine their respective contributions to semantic processing over time. The results revealed that both linguistic and visual representational structures were reflected in neural activity during word processing, but with distinct temporal profiles. Visual information contributed at earlier stages of processing, with significant effects emerging approximately 100 ms after stimulus onset and extending across multiple processing stages. In contrast, linguistic information emerged later, around 170 ms after stimulus onset, and exhibited a more temporally restricted pattern. Furthermore, both representational sources explained unique variance in neural similarity patterns when considered simultaneously. These findings suggest that conceptual processing during word recognition involves the interaction of both perceptual and linguistic representations, which unfold according to partially distinct temporal dynamics. More broadly, the present study provides support for contemporary multimodal accounts of conceptual representation and highlights the value of time-resolved EEG-RSA for investigating the temporal organization of semantic cognition. Keywords: Semantic cognition, Conceptual representation, Electroencephalography (EEG), Representational Similarity Analysis (RSA), Multimodal semantics