J. Danckert et P. Maruff, MANIPULATING THE DISENGAGE OPERATION OF COVERT VISUAL-SPATIAL ATTENTION, Perception & psychophysics, 59(4), 1997, pp. 500-508
Processes of covert visual spatial attention have been closely linked
to the programming of saccadic eye movements. In particular, it has be
en hypothesized that the reduction in saccadic latency that occurs in
the gap paradigm is due to the prior disengagement of covert visual sp
atial attention. This explanation has received considerable criticism.
No study as yet has attempted to demonstrate a facilitation of the di
sengagement of attention from a covertly attended object. If such faci
litation were possible, it: would support the hypothesis that the pred
isengagement of covert attention is necessary Tur the generation of ex
press saccades. In two experiments using covert orienting of visual at
tention tasks (COVAT), with a high probability that targets would appe
ar contralateral to the cued location, we attempted to facilitate the
disengagement of covert attention by extinguishing peripheral cues pri
or to the appearance of targets. We hypothesized that the gap between
cue offset and target onset would facilitate disengagement of attentio
n from a covertly attended object. For both experiments, responses to
targets appearing after a gap were slower than were responses in the n
o-gap condition. These results suggest that: the prior offset of a cov
ertly attended object does not facilitate the disengagement of attenti
on.