A neuropsychological profile of attention deficits in young males with fragile X syndrome.

Different processes of attention were examined in a group of 25 fragile X boys with FMR-1 full mutation and compared with three control groups: a learning disabled comparison group comprising 25 boys with Down's syndrome, matched to the fragile X boys on verbal mental age; and 50 mainstream school boys (controls) matched to the fragile X boys on verbal mental age. The controls were further divided into those matched on "poor attention" to the fragile X boys and a "good" attention group, as rated by the ACTeRS questionnaire. Four categories of attention tasks were employed: selective attention, divided attention, sustained attention and executive functioning. The main findings of the study indicate that fragile X boys display an attention deficit at higher levels of attention function/executive functioning and that this profile is different from the profile identified in Down's syndrome boys and more extreme than the profile identified in the poor attention control group. These findings are discussed in the context of functional neuroimaging and brain-behaviour correlates in fragile X syndrome.