Unfamiliar and newly learned face identification: An examination of individual differences

Abstract

Face identification involves two tasks: Recognizing an individual even when their appearance changes, and discriminating them from similar-looking individuals. People vary in the accuracy with which they identify unfamiliar faces. Much of the work investigating individual differences in face identification used tightly controlled stimuli (i.e., focused on discrimination). Few studies have used stimuli that incorporate variability in appearance (e.g., focused on recognition). Despite interest in individual differences, and understanding that recognizing a face across instances poses a difficult challenge, many gaps in the literature remain. These include potential predictors, the reliability and convergent validity of face identification tasks, and whether unfamiliar face identification predicts face learning efficiency. I examined a potential predictor of face identification—photography experience (Chapter 2). I recruited photography Experts, Hobbyists and Novices to take part in an unfamiliar face identification task. Photography experience was not a significant predictor of sensitivity in unfamiliar face identification. However, it was a predictor of response bias. I examined the reliability and convergent validity of face identification tasks (Chapter 3). Participants completed four unfamiliar face identification tasks on two days (study 1), or two versions (simultaneous and sequential) of three unfamiliar face identification tasks (study 2). Sensitivity to identity and bias were stable across time and tasks. Response times were fastest on trials that were congruent vs. incongruent with one’s bias, providing preliminary evidence that this reflects decision-making processes. I examined whether unfamiliar face matching predicts face learning efficiency (Chapter 4). Participants completed two unfamiliar face matching tasks and a novel face learning task (which tested recognition four times during learning). Individual differences in the slope of face learning were predicted by unfamiliar face matching ability. These differences appear to be driven by individual differences in recollection, not familiarity. My dissertation provides insights about individual differences in face identification. Individual differences in sensitivity in unfamiliar face identification were stable across time and tasks. They also predict face learning efficiency. My results suggest that face identification is not just a perceptual problem—it is influenced by decision making and other processes. These results have implications for face identification theories and applied settings.