Presentation-time measures of the effects of manipulations in colour space on discrimination of famous faces

Caricaturing the distinctive shape of famous faces can produce an advantage in reaction-time paradigms but the role of distinctive colour and intensity information in recognition of facial identity has not previously been explored. A presentation-time paradigm was developed by which stimuli could be presented for a range of brief display periods. Subjects were required to identify photo-realistic colour representations of famous faces which either were veridical, were caricatured in colour space, or had enhanced colour saturation and intensity contrast (as contrast controls). Recognition accuracy was greater when viewing the caricatured stimuli than either the veridical images or the contrast controls. The removal of colour information to produce grey-scale images also decreased accuracy of face recognition. Both results indicate that colour information aids differentiation of a class of natural stimuli with similar configurations. Thus it is demonstrated that caricaturing faces can be extended to the colour domain and, as with shape caricaturing, enhancement of distinctive information can produce a recognition advantage for famous faces.