Investigating spatial and semantic proximity in auditory processing with event-related potentials

We previously demonstrated an interplay between semantic and spatial proximity in auditory processing, with self-relevant stimuli (e.g., one’s own name) enhancing distance discrimination in extrapersonal space. Building on this result, we designed an event-related potentials (ERPs) experiment to understand the cerebral bases of this interaction, by varying proximity in distance and/or autobiographical dimensions. Participants listened to equiprobable stimuli consisting of their own name and an unfamiliar name, each convolved with binaural room impulse responses to simulate two distances (20 cm and 8 m, on both sides). In four blocks (randomly distributed), they were asked to count the stimulus that was semantically and spatially near (own name at 20 cm), spatially near only (unfamiliar name at 20 cm), semantically near only (own name at 8 m), or neither near (unfamiliar name at 8 m). We observed modulations in early sensory-evoked and late cognitive ERPs, reflecting acoustical variations (intensity/reverberation or phonetic characteristics) and proximity discrimination (distance from self in spatial or semantic attributes). Early and late interactions in target and non-target stimuli reflected bottom–up and top–down processes, suggesting automatic and selective attention. This study suggests that auditory perception integrates embodied and situated mental representations, enabling early detection of object proximity, i.e., potential relevance/threat.