| |
Abstract:
Abstract: Intersensory interactions can modify orienting
behaviours (Stein and Meredith, 1993), such as eye movements.
Visually guided saccades curve away from a visual non-target to
which observers direct covert attention (e.g., Sheliga et al.,
1994). We examined the influence of visual, auditory and tactile
non-targets upon the trajectories of visually guided saccades using
a paradigm in which a saccade to a visual target was generated
following the occurrence of a task-relevant distractor, or
imperative stimulus, in the periphery. We recorded eye movements to
target LEDs located at 15 degrees above or below a central fixation
LED. Imperative stimuli were 15 degrees to the left or right of
fixation in the upper hemifield. Visual (LED onset), auditory
(noise) and tactile (vibratory stimulus) distractors were employed
in different blocks but were absent in control trials. Curved
saccade trajectories were observed in test and control conditions
and there was a significant effect of non-target location upon the
direction of curvature, particularly when visual imperative signals
were employed: saccades curved to the left when the imperative
stimulus was on the right and vice versa. Results further support
the link between covert and overt orienting asserted by the
premotor hypothesis (Rizzolatti, 1983) and highlight a useful
paradigm for studying intersensory and intrasensory interactions.
(Funded by Wellcome Trust, UK.)
|
