No global processing deficit in the Navon task in 14 developmental prosopagnosics.
Faces are represented in a more configural or holistic manner than other objects. Substantial evidence indicates that this representation results from face-specific mechanisms, but some have argued that it is produced by configural mechanisms that can be applied to many objects including words. The face-specific hypothesis predicts that non-face configural processes will often be normal in prosopagnosic subjects, whereas the domain-general configural hypothesis predicts they will be deficient on all configural tasks. Although the weight of the evidence favors the face-specific hypothesis, a recent study reopened this issue when it was found that three out of five developmental prosopagnosics showed a larger local processing bias than controls in a global-local task (i.e. a Navon task). To examine this issue more thoroughly we tested a significantly larger sample of prosopagnosics (14 participants) who had severe face memory and face perception deficits. In contrast to the previous report, the developmental prosopagnosics performed normally in the global-local task. Like controls, they showed a typical global advantage and typical global-to-local consistency effects. The results demonstrate that the configural processing required by the Navon task is dissociable from face configural processing.
Duchaine
Bradley
B
Institute of Cognitive Neuroscience, University College London, 17 Queen Square, London WC1N3AR, UK. b.duchaine@ucl.ac.uk
Yovel
Galit
G
Nakayama
Ken
K
D000293:Adolescent; D000328:Adult; D005149:Facial Expression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010364:Pattern Recognition, Visual; D020238:Prosopagnosia / Q000175:diagnosis* / Q000453:epidemiology; D012720:Severity of Illness Index; D055815:Young Adult