Semantic information can facilitate covert face recognition in congenital prosopagnosia

Abstract

People with congenital prosopagnosia have never developed the ability to accurately recognize faces. This single case investigation systematically investigates covert and overt face recognition in “C.,” a 69 year-old woman with congenital prosopagnosia. Specifically, we: (a) describe the first assessment of covert face recognition in congenital prosopagnosia using multiple tasks; (b) show that semantic information can contribute to covert recognition; and (c) provide a theoretical explanation for the mechanisms underlying covert face recognition.

Keywords:

• Congenital prosopagnosia
• Covert face recognition
• Name recognition
• Developmental prosopagnosia
• Models of face recognition
• Face recognition

Ethics declaration: The current study was approved by the Ethics Committees of Macquarie University and has therefore been conducted in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki. Informed consent was obtained from all participants. Thank you to C. Ellie Wilson for designing and programming the famous face recognition task, Alan Taylor for his statistical advice, and to C. for her time and patience. Thank you also to A. Mike Burton and Brad Duchaine for helpful comments on this work.

Notes

¹Stimuli for the Mooney Faces Task, the Composite Faces Task, and the Jane Task were provided by the McMaster Vision Lab. For a detailed description of the stimuli see Mondloch, Le Grand, and Maurer (2003), Le Grand, Mondloch, Maurer, and Brent (2004), and Mondloch, Le Grand, and Maurer (2002) respectively.

²Whereas in previous studies the Composite Faces Task has mostly been presented as a sequential matching task (i.e., for each pair of composite faces participants were presented with one stimulus after the other in a rapid sequence), in our study the task was presented as a paired matching task (i.e., the composites of each pair were presented simultaneously). Due to the reduced difficulty of a paired matching versus a sequential matching task, we observed a composite effect only in reaction time (whereas previous studies have reported composite effects for both accuracy and reaction time).

³As for the Composite Faces Task, the Jane Task has mostly been presented as a sequential matching task in previous studies (i.e., for each pair of faces participants were presented with one stimulus after the other in a rapid sequence), whereas in our study it was presented as a paired matching task (i.e., the stimuli of each pair were presented simultaneously).