Does acquisition of Greeble expertise in prosopagnosia rule out a domain-general deficit?

► We tested the specificity of impairment in a prosopagnosic individual (LR) who uses only a single feature to identify faces. ► LR was able to reach expertise criterion for Greebles, though he took many more training sessions than controls. ► Post-tests revealed that LR used only a single feature to identify Greebles, whereas controls used multiple features. ► LR's face recognition deficit is the most apparent symptom of a more general impairment in expertise-related visual processing. ► Even when performance for object recognition is high, a range of paradigms is helpful to assess how recognition is accomplished.