The distracting impact of repeated visible and invisible onsets on focused attention.

A sudden peripheral onset is a powerful attentional attractor. However, in real life potentially distracting events do not always occur as a single event, but rather they can occur in a repetitive fashion. Hence, one of the aims of the present study was to investigate how the attentional system reacts to multiple consecutive onsets within the same trial. The results, quite surprisingly, showed that repeated peripheral onsets do not have a negative impact on visual performance, while they confirmed that a single peripheral onset captures focused attention. We hypothesize the existence of a short-term habituation mechanism that prevents visual attention from being continuously distracted by the same task-irrelevant event when this is rapidly repeated. A further aim of the study was to test the proposal according to which subliminal visual transients can bypass the conscious inhibitory control, thus resulting more distracting than supraliminal transients. We did not find in any of the 8 experiments that we conducted that subliminal onsets, either single or repeated, can grab attention when fully focused at fixation. Hence, in the case of sudden onsets, the general claim that task-irrelevant invisible stimuli can be more disturbing than visible ones does not seem to be fully justified.