Image or Identity? Only Super-recognizers’ (Memor)Ability is Consistently Viewpoint-Invariant

Abstract

A face’s memorability refers to the unique combination of visual features facilitating its recognition. Despite considerable variation in face recognition ability amongst the general population, individuals show substantial concordance regarding faces’ memorability. This agreement persists, though reduced, when the viewpoints across which identities are seen at encoding and recognition differ. Consequently, individuals must extract some invariant facial information during recognition, robust to changes in viewpoint, to do so consistently (i.e. as a function of stimulus memorability). However, the extent of such consistency remains unclear. Therefore, in two experiments we tested recognition of (i) implicitly encoded face images and (ii) explicitly encoded identities in a group of control observers against a group of “Super-Recognizers” (SRs) possessing exceptional face processing skills (Ramon, 2021). Novel “With or Without You” (WoWY) resampling analyses assessed the consistency of SRs relative to control observers, simultaneously providing measures of intraindividual consistency. When implicit encoding was surreptitiously solicited (Experiment 1), recognition of studied images was comparable between groups. Yet, when encoding was explicitly solicited (Experiment 2), SRs more accurately recognized identities across viewpoint changes than controls. Critically, image-dependent information could only inform recognition in the first experiment, whereas viewpoint-invariant information could inform recognition equally in both. Individual observers’ performance profiles reveal that only SRs memorability-related performance was consistent between experiments. Overall, SRs’ unique capacity for recognizing faces based on viewpoint-invariant information is rooted in fundamentally more robust representations of identity. These results invite a reinterpretation of face memorability describing viewpoint-invariant information, diagnostic of facial identity representations in memory. <strong>Highlights</strong> <ul><li>Super-Recognizers (SRs) do not uniformly recognize face images better than controls; both SRs and control observers tend to recognize high- and low-memorability stimuli equally well.</li><li>Novel “With or Without You” analyses, combining split-half resampling and permutation techniques, revealed inter- and intra-individual consistency in recognition memory.</li><li>SRs excelled at explicit (but not implicit) learning of facial identities relative to controls when viewpoint-invariant information was task-relevant.</li><li>SRs consistently represent faces with identity-based (viewpoint-invariant) memorability, while controls use either image- or identity-based representations.<br />The finding that consistency of identity-based memorability is relatively unique to SRs suggests that it constitutes a potential marker of overall face recognition ability.</li></ul>