PRIMING EFFECT AS RELATED TO DIFFICULTY IN SELECTION FOR OVERLAPPING STIMULI MANIPULATED BY THE RELATIVE LINE THICKNESS OF ATTENDED AND UNATTENDED FIGURES
H. Kobari, PRIMING EFFECT AS RELATED TO DIFFICULTY IN SELECTION FOR OVERLAPPING STIMULI MANIPULATED BY THE RELATIVE LINE THICKNESS OF ATTENDED AND UNATTENDED FIGURES, Perceptual and motor skills, 86(3), 1998, pp. 1219-1230
The present study examined how difficulty of ignoring unattended stimu
lus affected the negative priming. To establish an experimental situat
ion with intentional ignoring, subjects were presented overlapping sti
muli consisting of two figures of different colors and were required t
o attend to one of the figures while ignoring the other. Moreover. the
difficulty in selection was manipulated by their line thickness. The
assumption was that the magnitude of that difficulty should increase w
ith the ratio of line thickness of the unattended figure to that of th
e attended one. Reaction time was measured in both ignored repetition
and control conditions. In the former, both the unattended figure in t
he prime and the attended one in the probe were of the same form, whil
e in the latter, they were different. Priming effect was indicated by
the difference between the two reaction times. Two experiments showed
that the printing effect changed with the ratio of line thickness, dep
icted as a V-shaped curve. The effect was facilitative at the ratio of
line thickness of 1, which was inconsistent with the previous studies
reporting an inhibitive effect. The following two experiments, howeve
r, confirmed that the effect at the ratio of I was facilitative when t
he ratio of line thickness was varied, but it was inhibitive when the
ratio of line thickness was fixed within a session. The inconsistency
could then be attributed to the difference in the manipulation of the
ratio of line thickness.