title: Alerting and orienting of attention without visual awareness.
abstract: Two types of the attentional network, alerting and orienting, help organisms respond to environmental events for survival in the temporal and spatial dimensions, respectively. Here, we applied chromatic flicker beyond the critical fusion frequency to address whether awareness was necessary for activation of the two attentional networks. We found that high-frequency chromatic flicker, despite its failure to reach awareness, produced the alerting and orienting effects, supporting the dissociation between attention and awareness. Furthermore, as the flicker frequency increased, the orienting effect attenuated whereas the alerting effect remained unchanged. According to the systematic decline in temporal frequency sensitivity across the visual hierarchy, this finding suggests that unconscious alerting might be associated with activity in earlier visual areas than unconscious orienting. Since high-frequency flicker has been demonstrated to only activate early visual cortex, we suppose that neural activation in early visual areas might be sufficient to activate the two attentional networks.
authors.affiliation: Department of Psychology and Behavioral Sciences, Zhejiang University, Hangzhou, Zhejiang, PR China. snlu@zju.edu.cn
authors.forename: Shena
authors.initials: S
authors.lastname: Lu
authors.forename: Yongchun
authors.initials: Y
authors.lastname: Cai
authors.forename: Mowei
authors.initials: M
authors.lastname: Shen
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhou
authors.forename: Shihui
authors.initials: S
authors.lastname: Han
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention; D001364:Awareness; D003463:Cues; D005260:Female; D005425:Flicker Fusion; D006801:Humans; D008297:Male; D010775:Photic Stimulation; D014796:Visual Perception; D055815:Young Adult