EEG Signatures of Auditory Distraction: Neural Responses to Spectral Novelty in Real-World Soundscapes

In everyday life, ambient sounds can disrupt our concentration, interfere with task performance, and contribute to mental fatigue. Even when not actively attended to, salient or changing sounds in the environment can involuntarily divert attention. Understanding how the brain responds to these real-world auditory distractions is essential for evaluating the cognitive consequences of environmental noise. In this study, we recorded electroencephalography (EEG) while participants performed different tasks during prolonged exposure to a complex urban soundscape. We identified naturally occurring, acoustically salient events and analyzed the corresponding event-related potentials (ERPs). Auditory spectral novelty reliably elicited a P3a response (250-350 ms), reflecting robust attentional capture by novel environmental sounds. In contrast, the Reorienting Negativity (RON) window (450-600 ms) showed no consistent modulation, possibly due to the continuous and largely behaviorally irrelevant nature of the soundscape. Performance in a behavioral task was briefly disrupted following novel sounds, underscoring the functional impact of attentional capture. Noise sensitivity, measured via the Weinstein Noise Sensitivity Scale (WNSS; 1978), was not associated with ERP amplitudes. Together, these findings demonstrate that the P3a component provides a stable neural marker of attentional shifts in naturalistic contexts and highlight the utility of spectral novelty detection as a tool for investigating auditory attention outside the laboratory.