[A neuropsychological and behavioural profile of attention deficits in fragile X syndrome].
BACKGROUND
Fragile X syndrome is a well-recognised cause of developmental delay in males and to a lesser extent females. The aim of the present study was to present a detailed cognitive and behaviour analysis of the core attention impairments frequently associated with fragile X.


METHODS
Two complementary studies were conducted. Study 1 examined the severity and range of behavioural problems in a group of 25 fragile X boys with fragile X compared with five control groups: a learning disabled comparison group (Down's syndrome-Trisomy 21) and four groups of normal developing control children. Two well validated rating scales were used as measures of behaviour: Study 2 examined performance by the above groups on a novel computerised task of attention that measured the ability to inhibit irrelevant responses.


RESULTS
Findings from Study 1 revealed that fragile X children were significantly more hyperactive, inattentive and impulsive in comparison with the Down's syndrome children but not in comparison to the poor attention control groups. The findings from Study 2 revealed that the main impairment in fragile X was in inhibiting repetition of successful responses and in switching attention from one type of response to another in a sequence, whether it has been successful or not.


CONCLUSIONS
Emerging evidence now supports the hypothesis that the fundamental deficit in fragile X is in controlling the flow of sequences of input and output. It is suggested that this control require inhibition.
Cornish
K
K
Section of Developmental Psychiatry, Divisiono f Psychiatry, University of Nottingham, Jubilee Campus, Nottingham, United Kingdom.
Munir
F
F
Wilding
J
J
D000293:Adolescent; D001288:Attention / Q000502:physiology*; D001289:Attention Deficit Disorder with Hyperactivity / Q000209:etiology / Q000503:physiopathology*; D002648:Child; D002652:Child Behavior / Q000502:physiology*; D002675:Child, Preschool; D002658:Developmental Disabilities / Q000503:physiopathology; D004314:Down Syndrome / Q000503:physiopathology; D005260:Female; D005600:Fragile X Syndrome / Q000150:complications / Q000503:physiopathology*; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests