A new study led by Dr. JIANG Yi from the Institute of Psychology of the Chinese Academy of Sciences has revealed the first clear evidence that visual awareness acts as a "conductor" that refines the speed, precision, and neural coordination of attentional rhythmic sampling. 

Published in Nature Communications on Nov. 17, this study resolves a long-standing mystery about the interplay between attention and consciousness, opening new avenues for understanding cognitive function and deficits.

For decades, attention has been likened to a mental "spotlight," illuminating critical information while sidelining distractions. However, recent research has revealed that this spotlight is not static; it oscillates rhythmically (4–8 Hz in humans and monkeys) and samples information even when focused on a single target. 

Despite progress in decoding the neural basis of this rhythmic sampling, its relationship with conscious awareness remained unexplored until now. Researchers sought to answer: Can attention sample rhythmically without conscious awareness? And if so, how does awareness shape this process?

To address these questions, the researchers combined cutting-edge techniques to isolate the role of visual awareness in rhythmic attentional sampling. Using chromatic flicker fusion technology, they rendered visual cues invisible by rapidly alternating two gratings of opposite colors at 30 Hz—beyond the visual system's fusion threshold—making them perceptually indistinguishable from the background. 

By combining this approach with high–temporal-resolution cueing paradigms, electroencephalography, and temporal response function analysis, the researchers examined how visible and invisible cues induce different attentional dynamics and neural responses.

The results show that rhythmic attentional sampling can be induced by invisible cues. More intriguingly, when the cues were consciously visible, they elicited stronger distractor suppression, drove faster rhythmic sampling (~8 Hz vs. ~4 Hz), and greater neural coherence at higher frequencies between the frontal and occipito-parietal regions.

"Visual awareness is not an on-off switch for rhythmic attention, but a powerful regulator that optimizes the process," said Dr. YANG Fang, first author of the study. "It makes attention more flexible, selective, and efficient by sharpening information selection, speeding up the sampling cycle, and refining large-scale neural coordination."

This study opens a new window into the dynamic interplay between attention and consciousness. It deepens our understanding of how the emergence of consciousness helps filter the flood of sensory input and provides new avenues for investigating the neural mechanisms underlying attention deficits from the perspective of the interaction between consciousness and attention.

The research was supported by the Ministry of Science and Technology of China and the National Natural Science Foundation of China.

This figure uses SUN Wukong's (the Monkey King) iconic "Fiery Eyes of Truth" as a metaphor for rhythmic attentional sampling, illustrating how visual awareness modulates the process. SUN Wukong's Fiery Eyes (representing attentional sampling) emit focused, beam-like signals toward an iceberg—half exposed above the sea (conscious state) and half submerged below (unconscious state). Beams targeting the exposed (conscious) segment produce faster, brighter halos, matching the accelerated sampling optimized by visual awareness. In contrast, beams aimed at the submerged (unconscious) segment create slower, dimmer halos, reflecting baseline sampling that persists without awareness. (Image by Drs. JIANG Yi and YANG Fang)