Multisensory templates exert top-down control on contingent attentional
capture. (a) The experiment design of the task and trial sequence.
The target and nontarget search displays of the two tasks are illustrated. One
is the visual task, in which participants were asked to discriminate whether the
red bar was vertical or horizontal. The other is the audiovisual task, in which
participants were asked to discriminate between vertical and horizontal red bars
when they were accompanied by a high-pitched tone (illustrated here as a 2000 Hz
tone). Thus, the blue bars or low pitches (the nontarget search displays) were
to be ignored. Each trial began with the cue array, which was composed of six
elements, each consisting of four closely aligned dots. One element was a color
singleton that matched the target color (illustrated here as
“red”). The red singleton was presented randomly and with equal
probability at one of the four lateral locations but never at the top or bottom
locations. The visual target (the red vertical or horizontal bar) and the visual
nontarget (the blue vertical or horizontal bar) were presented in the same
manner as the cue. In the cued trials, the visual target or nontarget was
presented at the ipsilateral (same) side as the cued singleton, while in the
uncued trials, the visual target or nontarget was presented on the contralateral
(opposite) side. (b) Behavioral results. Spatial cueing effects,
which were calculated by subtracting the reaction time for the cued targets from
that for the uncued targets, were found in both the visual and audiovisual
tasks. More interestingly, the amplitude of the spatial cueing effect in the
visual task was larger than that in the audiovisual task. (c) ERP
results. The grand average ERP measured at the posterior electrodes PO7/8
contralateral and ipsilateral to the location of a target-color singleton cue.
The difference waveforms that were obtained by subtracting the ipsilateral from
the contralateral ERPs are illustrated separately for the visual (gray) and
audiovisual tasks (green). The N2pc is marked and is an enhanced negativity that
emerges approximately 200 ms after the onset of the target-color singleton cue.
The results revealed that the amplitude of the N2pc component was larger in the
visual task than in the audiovisual task. Adapted with permission from the
corresponding author (Matusz and Eimer,
2013). Copyright © 2013 Society for Psychophysiological
Research.