L. Buchanan et al., A REEXAMINATION OF THE VISUOSPATIAL DEFICIT IN TURNER-SYNDROME - CONTRIBUTIONS OF WORKING-MEMORY, Developmental neuropsychology, 14(2-3), 1998, pp. 341-367
Studies describing deficits in children with Turner Syndrome (TS) typi
cally report that visual and spatial processing are impaired relative
to verbal processing (Rovet & Netley, 1982). The exact nature of this
deficit is not entirely clear, however, because the tasks that have be
en used to date (e.g., mental rotation, part-whole and left-right deci
sions, etc.) do not distinguish between what Kosslyn (1980) described
as the two components of visual processing: locating an object in spac
e (where?) and determining the identity of an object (what?). We repor
t findings from an experiment designed to examine visual processing an
d working memory in children with TS and normal control children. Howe
ver, unlike previous examinations of visuospatial processing in TS, th
e reported experiments tease apart what and where aspects of the visua
l system. Moreover, they examine separately the contributions of both
visual and verbal working memory to visuospatial processing. Differenc
es between children with TS and normal controls indicate that the core
deficit is in visuospatial working memory. Correlations with karyotyp
e information from the girls with TS provide some preliminary support
for a gene-dosage hypothesis.