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

of the Arabic number system within the representation of number magnitude, the neurofunctional
implications of the auditory-verbal and the visual number form representation will
not be specified any further.
Triple Code Model
Autitory verbal
Code
arithmetic facts
two x four = “eight“
Analog magnitude
Representation
Comparison
Estimation
Visual Arabic
Number form
{1, 2 ,…8 ,9}
Figure 2:
Dehaene & Cohen’s (1995) Triple Code Model (adapted from Cohen &
Dehaene, 1995, p. 132)
In summary, it is evident, that the two models differ substantially in respect of the
implementation of the place-value structure of the Arabic number system. On the one hand,
an amodal semantic representation of number magnitude is at the heart of McCloskey’s model
and this magnitude representation is organized along place-value constraints. On the other
hand, within the framework of the Triple Code Model place-value structuring is not assumed
for the representation of analogue magnitude. Instead, the magnitude of any number is
represented by a holistic code not including place-value information. Anyway, there is some
inconsistency within the Triple Code Model regarding the influence of place-value
information. For the case of multi-digit arithmetic, in particular addition and subtraction
Dehaene and Cohen (1995) propose a solution process based on repetitively solving single
digit problems at corresponding place-value positions, i.e., at the same power level [e.g., 24 +
61 = (2 + 6) * 10 1 + (4 + 1) * 10 0 ].
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