摘要：Various sources of information demonstrate a tight link between visuospatial and
nu-merical disabilities. In the past, this link has been attributed to the
involvement of visuospa-tial peripheral support systems like for instance
visuospatial working memory in numerical cognition. However, it is also possible
that the association of visuospatial and numerical abilities has a more basic
origin. The basic mental representation of numerical magnitude has been shown to
take the form of an oriented mental number line in normally developing chil-dren
and adults, as evidenced by the SNARC effect (preference for left-hand responses
to small numbers and right-hand responses to large numbers). To investigate the
possibility of abnormal spatial number coding in children with combined
visuospatial and numerical dis-abilities, we measured the SNARC effect in a
visuospatial disability group (VSD) during a number comparison task (smaller or
larger than 5) and compared it to a matched control group. A SNARC effect was
obtained in the control group but not in the visuospatial disabil-ity group.
This result is a first indication that the link between visuospatial and
numerical disabilities may be mediated by a basic abnormality in representing
numerical magnitudes on an oriented mental number line.
