Illusions of face memory: Clarity breeds familiarity.

When people perform a recognition memory task, they may avail themselves of different forms of information. For example, they may recall specific learning episodes, or rely on general feelings of familiarity. Although subjective familiarity is often valid, it can make people vulnerable to memory illusions. Research using verbal materials has shown that "old" responses are often increased by enhancing perceptual fluency, as when selected words are shown with relatively higher contrast on a computer. Conversely, episodic memory can create an erroneous sense of perceptual advantages for recently studied words. In this investigation, symmetric fluency effects were tested in face memory, a domain that is often considered neurologically and psychologically unique. In eight experiments involving over 800 participants, we found consistent memorial and perceptual illusions-fluency created feelings of familiarity, and familiarity created feelings of fluency. In both directions, these effects were manifested as response biases, suggesting effects based on memorial and perceptual attributions.