The frequency and severity of specific cognitive deficits in 81 children with neurofibromatosis type 1 (NF1), ages 8 to 16 years, compared to 49 unaffected sibling controls, were assessed in a study at the University of Sydney, New South Wales, Australia. Specific learning disabilities, defined by IQ-achievement discrepancies, occurred in 20% (37% in males and 5% females), but 51% showed impairments in reading, spelling, and mathematics, and 81% had moderate to severe impairments in cognitive functioning. Mental retardation was present in 6 - 7%. Attention deficit hyperactivity disorder was diagnosed in 38%, while 63% had sustained attention difficulties. Compared with their siblings, ADHD was 3 times more common in NF1 children, with similar frequencies in males and females. An NF1 neuropsychological profile shows deficits in visuo-spatial and -perceptual skills, executive functioning, attention, and expressive and receptive language. Verbal and visual memory was preserved. 
COMMENT. A neuropsychological profile for neurofibromatosis type 1 is characterized by weaknesses in visuospatial and visuoperceptual skills and strengths in verbal and visual memory. Specific learning disabilities are particularly prevalent in males, and girls are relatively spared. Comorbidity with ADHD is prevalent, both in males and females with NF1.