Visual orienting in the early broader autism phenotype: disengagement and facilitation.
BACKGROUND
Recent studies of infant siblings of children diagnosed with autism have allowed for a prospective approach to examine the emergence of symptoms and revealed behavioral differences in the broader autism phenotype within the early years. In the current study we focused on a set of functions associated with visual attention, previously reported to be atypical in autism.


METHODS
We compared performance of a group of 9-10-month-old infant siblings of children with autism to a control group with no family history of autism on the 'gap-overlap task', which measures the cost of disengaging from a central stimulus in order to fixate a peripheral one. Two measures were derived on the basis of infants' saccadic reaction times. The first is the Disengagement effect, which measures the efficiency of disengaging from a central stimulus to orient to a peripheral one. The second was a Facilitation effect, which arises when the infant is cued by a temporal gap preceding the onset of the peripheral stimulus, and would orient faster after its onset.


CONCLUSIONS
Infant siblings of children with autism showed longer Disengagement latencies as well as less Facilitation relative to the control group. The findings are discussed in relation to how differences in visual attention may relate to characteristics observed in autism and the broader phenotype.
Elsabbagh
Mayada
M
Centre for Brain & Cognitive Development, Birkbeck, University of London, London, UK. m.elsabbagh@bbk.ac.uk
Volein
Agnes
A
Holmboe
Karla
K
Tucker
Leslie
L
Csibra
Gergely
G
Baron-Cohen
Simon
S
Bolton
Patrick
P
Charman
Tony
T
Baird
Gillian
G
Johnson
Mark H
MH
D001321:Autistic Disorder / Q000175:diagnosis* / Q000235:genetics / Q000523:psychology*; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009949:Orientation; D010775:Photic Stimulation; D035781:Siblings / Q000523:psychology*; D013028:Space Perception; D013997:Time Factors; D014796:Visual Perception