Electrophysiological evidence for temporal dynamics associated with attentional processing in the zoom lens paradigm

• DOI: 10.7717/peerj.4538
• Publication Date: 2018-04-03T07:26:53Z
• Authors: Qing Zhang; Tengfei Liang; Jiafeng Zhang; Xueying Fu; Jianlin Wu
• Keywords: N2pc; Visual Search; Visual processing; Visual spatial attention

Background Visuospatial processing requires wide distribution or narrow focusing of attention to certain regions in space. This mechanism is described by the zoom lens model and predicts an inverse correlation between efficiency size attentional scope. Little known, however, about exact timing effects scaling on visual searching whether not additional phases are involved this process. Method Electroencephalographic recordings were made while participants performed a search task under different conditions. Two concentric circles sizes, presented at center screen modulated scopes, arrays distributed space areas indicated these circles. To ensure consistent eccentricity across conditions, we limited our studies neural responses evoked overlapping region scopes. Results Consistent with prediction model, behavioral data showed that reaction times for target discrimination decreased associated error rates also significantly decreased, narrowing event-related potential analysis target-elicited amplitude lateral occipital N1, rather than posterior P1, which reflects earliest visuospatial processing, was sensitive changes attention, indicating modulation effect spatial scale occurred after delay period P1. The N1 generator exhibited higher activity as scope narrowed, reflecting more intensive resources within focus. In contrast N2pc increased expansion focus, suggesting observers might further redistribute according difficulty. Conclusion These findings provide electrophysiological evidence marker attention. Furthermore, from shows there redistribution action mechanism, allows better perform context low resolution. On basis N2pc, compelling paradigm involves multi-stage dynamic processing.