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Abstract:
Previous research has shown that children as young as 6
orient attention automatically and covertly following a spatial
cue. We investigated the effect of covert orienting of visual
attention on visual discrimination in 7-11 year old children. In
our spatial discrimination task, an attention-directing cue (box
brightening) was followed at intervals of 100 or 800 ms by a target
stimulus (an "E" oriented to the right, left, up or down) in the
cued or non-cued location. To assess visual discrimination under
full (focused) attention, the target was presented in the same cued
location and a mask followed 50, 100, 250, 500, or 1000 ms. To
assess visual discrimination with and without covert attention, the
target was presented in the cued (80%) or non-cued (20%) location,
and was masked following 50 or 100 ms. Subjects moved a joystick to
indicate the direction of the "E". Results demonstrated age-related
differences in processing speed in the focused attention task.
Younger children required longer target-to-mask intervals to
process accurately. Age-related differences were also evident in
the 'validity effect' following spatial cueing (accuracy at cued
minus non-cued locations). Younger children were slower to orient
to a cued location, and showed greater costs when the target
appeared in the non-cued location. These results suggest
developmental trends in covert visual attention mechanisms.
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