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

intergration is specifically relevant. When neglect patients would exhibit particular
impairments in these triplets this would indicate that neglect not only hinders the
processing of magnitude information but also of structural information when presented
with two-digit numbers. In turn, this would imply that the mental number line
incorporates such structural place-value information.
Section 5: A computational model of place-value integration in two-digit number
comparison
Study 7: Two-digit number processing – holistic, decomposed or hybrid? A
computational modelling approach
This last study is not an empirical study, but aimed at clarifying an issue for
which there is currently no empirical resolution. At the moment there are three
different conceptualizations of how number magnitude representation may be
organized. The assumption of a holistic representation sees the magnitude of a number
to be represented as a single integrated entity, thereby not retaining the place-value
structure of the Arabic number system. Contrarily, the strictly decomposed view
assumes that each power level of a given number (e.g., tens and units of two-digit
numbers) is represented separately. Finally, the hybrid model of number magnitude
representation is a combination of the former two models assuming both decomposed
representations of the individual power levels as well as an overall holistic
representation of a given number. In particular, the strictly decomposed and the hybrid
model cannot be differentiated on the based of empirical data. Therefore, three
network models corresponding to each of above mentioned representational models
were programmed to evaluate which of these models accounts best for the
accumulated empirical data. Particular interest was paid whether the models would
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