MATERIAL and METHODS: The Wechsler Intelligence Scale for Children-Revised (WISC-R) test was applied to healthy children (control group), hydrocephalic children (hydrocephalus group) and children with ADHD (ADHD group); and the test results were statistically analyzed with the Multivariate Analysis of Variance (MANOVA) and linear logistic regression test.

RESULTS: All test results of the hydrocephalus group were significantly worse than the ADHD and control groups. However, the ADHD group showed performances as good as the control group at the tests except for the arithmetic, digit span, block design, object assembly and coding subtests.

CONCLUSION: The WISC-R results suggested that the ADHD group has more difficulties with their encode, focused/execute attention and sustain attention than visual attention. However, children with hydrocephalus have much more problems with their visuospatial perception, material organization and attention (especially encode, focused/execute attention and sustain attention); and these problems could produce adaptive problems in their social, cultural, behavioral and academic achievement. Keywords : Attention, ADHD, Hydrocephalus, WISC-R