摘要：When comparing 2-digit Arabic numbers, not only the relevant semantic relations
be-tween numbers are computed, but also irrelevant ones, like the unit-decade
compatibility effect (Nuerk, Weger, & Willmes, 2001). As pointed out by
Nuerk and Willmes (this issue), the magnitude representations of decade and unit
digit may be activated beside the semantic representation of the two-digit
magnitude. The magnitude representation of units and dec-ades may produce
congruity effects, which have not been explored yet. Here we examine different
forms of digit congruity produced by the mode of presentation of the stimuli,
and how the congruity of decade and unit digits may interfere with the normal
two-digit number processing. In two experiments participants were asked to
identify the larger of two two-digit Arabic numbers. Unit- and decade digits
were presented in different combinations within a short time interval, so that
the two-digit structure was perceptually disturbed. Re-gression analyses
revealed that in both Experiments 1 and 2 the semantic congruity of the digits
being presented simultaneously led to a bias in response times which strongly
inter-fered with the decade distance and compatibility effects. Our results
suggest that the seman-tic comparison of 2-digit Arabic numbers may also be
determined by congruity relations between the digits of these numbers.
Implications for presenting one two-digit number in a comparison with a fixed
standard are discussed.
关键词：two-digit number processing, unit-decade compatibility effect, second-order
congruity
