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

From a developmental point of view it is interesting that none of the current models of
numerical development (e.g., von Aster & Shalev, 2007; Butterworth, 2005; Wilson &
Dehaene, 2007; Rubinsten & Henik, 2009) considers the role of place-value understanding,
explicitly. Nevertheless, based on recent findings suggesting particular effects of place-value
processing in children (e.g., Nuerk et al., 2004; Moeller et al., 2009c; Pixner et al., 2009)
Study 4 specifically addressed the question of place-value understanding in numerical
development in a longitudinal design. Therein, indices of place-value processing from a
variety of basic numerical tasks such as magnitude comparison and transcoding were assessed
in first grade and their predictive value for children’s performance in an addition task
administered two years later was inspected. To date, such longitudinal influences have only
been investigated for the case of children’s number magnitude representation (Holloway &
Ansari, 2009; Halberda, Mazzocco, & Feigenson, 2008) but not for structural aspects such as
place-value understanding. So, Study 4 of the current thesis aimed at replicating previous
findings but for another basic numerical representation by combining specific aspects of prior
studies (e.g., Zuber et al., 2009 on the influence of place-value information in transcoding;
Pixner et al., 2009 on place-value integration in first-graders performing a two-digit
magnitude comparison; Study 2 on decomposed processing in two-digit addition) to
investigate the longitudinal development of numerical capabilities as determined by children’s
mastery of the place-value structure of the Arabic number system.
As the evidence corroborating the notion of decomposed processing of multi-digit
number from classical behavioural and developmental studies accumulates, further neuropsychological
aspects regarding such processing are of particular interest. On the one hand,
the question if and if so in what way place-value processing is affected by neuropsychological
disorders such as hemi-spatial neglect arises. On the other hand, the question regarding
possible neural correlates of place-value processing comes up. Both of these were addressed
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