The influence of the place-value structure of the Arabic number ...

The debate under which conditions holistic two-digit number processing dominates or
replaces decomposed processing of tens and units continues (Zhou, Chen, Chen, & Dong, in
press; see Nuerk & Willmes, 2005 for a review). The current data have a clear message
concerning this controversy: decomposed processing does not rely on external
representations, but can also be demonstrated even when internal representations are
involved. This suggests that two-digit numbers can be represented in a decomposed fashion
irrespective of their representational format (i.e. external or internal). And actually, this
finding has an everyday implication as whenever we judge whether a price is expensive or
not, we compare this price to an internal standard which deems us (approximately)
appropriate. However, a possible limitation of this interpretation may be that both Zhang and
Wang (2005) and Zhou et al. (in press) report unit-based null effects when the to be compared
numbers were presented serially rather than simultaneously. Therefore, the particular
influence of this distinction cannot be answered by the current results but has to be addressed
in future research. Nevertheless, what the current results do indicate is that the decomposition
of two-digit numbers is not limited to the external representational format but generalizes to
the internal representation as well.
A word on the logarithmic fitting of overall distance
Previously, (e.g. Dehaene et al., 1990) logarithmic fittings of the distance effects for
two-digit numbers have been used to indicate holistic rather than decomposed processing. It
was argued before (Nuerk & Willmes, 2005, see also Verguts & de Moor, 2005, for similar
arguments) that a good fit of overall logarithmic distance can be produced by decomposed as
well as by holistic models. In the present study, some parameters have been changed as
compared to previous studies: different standards (53 and 57) allowing for larger unit
distances were used together with 50 % of within-decade trials as compared to a much lower
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