Faces as objects of non-expertise: processing of thatcherised faces in congenital prosopagnosia.
Congenital prosopagnosia (cPA) is a severe disorder in recognising familiar faces, a human characteristic that is presumably innate, without any macro-spatial brain anomalies. Following the idea that cPA is based on deficits of configural face processing, we used a speeded grotesqueness decision task with thatcherised faces, since the Thatcher illusion can serve as a test of configural disruption (Lewis and Johnston, 1997 Perception 26 225-227). The time needed to report the grotesqueness of a face in relation to orientation showed dissociate patterns between a group of fourteen people with cPA and a group of matched controls: whereas the RTs of controls followed a strong sigmoid function depending on rotation from the upright orientation, the RTs of people with cPA showed a much weaker sigmoid trend approaching a linear function. The latter result is interpreted as a diagnostic sign of impaired configural processing, being the primary cause of the absence of 'face expertise' in prosopagnosia.
Carbon
Claus-Christian
CC
Faculty of Psychology, University of Vienna, Liebiggasse 5, A 1010 Vienna, Austria. ccc@experimental-psychology.com
Grüter
Thomas
T
Weber
Joachim E
JE
Lueschow
Andreas
A
D000328:Adult; D000704:Analysis of Variance; D016022:Case-Control Studies; D005145:Face; D005197:Famous Persons; D005260:Female; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology*; D020238:Prosopagnosia / Q000523:psychology*; D011930:Reaction Time; D021641:Recognition, Psychology / Q000502:physiology*; D012044:Regression Analysis