Neural evidence for the contribution of holistic processing but not attention allocation to the other-race effect on face memory

Examining the Contribution of Physical Cues for Same- and Cross-Race Face Individuation

Face individuation involves sensitivity to physical characteristics that provide information about identity. We examined whether Black and White American faces differ in terms of individuating information, and whether Black and White perceivers differentially weight information when judging same-race and cross-race faces. Study 1 analyzed 20 structural metrics (e.g., eye width, nose length) of 158 Black and White faces to determine which differentiate faces within each group. High-utility metrics (e.g., nose length, eye height, chin length) differentiated faces of both groups, low-utility metrics (e.g., face width, eye width, face length) offered less individuating information. Study 2 (N = 4,510) explored Black and White participants' sensitivity to variation on structural metrics using similarity ratings. High-utility metrics affected perceived dissimilarity more than low-utility metrics. This relationship was non-significantly stronger for same-race faces rather than cross-race faces. Perceivers also relied more on features that were racially stereotypic of the faces they were rating.

More elaborate processing of own-race faces and less elaborate processing of other-race faces contribute to the other-race effect in face memory

Research suggests that own-race faces are naturally memorized in a more elaborate (e.g., many features of a face or the whole face) way, whereas other-race faces are memorized in a less elaborate (e.g., only selected features of the face) manner. Here, we tested if instructions for judgements about the whole face and a single facial feature modulated the other-race effect in face memory. White participants performed whole-face and single-feature tasks while memorizing White and Black faces for later recognition. Encoding instructions had a stronger impact on own-race than other-race faces. Whole-face instructions increased the other-race effect, whereas single-feature instructions decreased it. Own-race faces in the whole-face task demonstrated event-related potential (ERP) patterns of memory encoding comparable to previously observed natural memory encoding, suggesting naturally more elaborate encoding of own-race faces. ERPs of memory encoding for other-race faces were similar between task conditions and comparable to previously observed natural encoding patterns, suggesting naturally less elaborate encoding. No impact of the encoding tasks was found on ERPs related to memory retrieval, which may be an artefact of a perceptual task that does not enhance semantic details in memory. The current results indicate that some contributions to the other-race effect are more elaborate (more detailed) memory encoding for own-race faces and less elaborate (less detailed) memory encoding for other-race faces. This study also provides evidence for more malleability of own-race than other-race faces through task instructions, consistent with assumptions of perceptual learning theories of the other-race effect.

Facial expressions of anger improve neural correlates of memory retrieval but not encoding of only same-race faces

The other-race effect is the phenomenon that people are better able to recognize and remember faces of their same race. Angry faces have been shown to facilitate processes that promote face recognition as reflected in the proportion of remembered faces after study. The other-race effect may be diminished when other-race faces display negative expressions, but no event-related potential studies have examined whether this improvement in other-race face recognition occurs during facial encoding or recognition. The current study used the old-new recognition task to examine whether anger reduces the other-race effect by improving face memory for other-race faces in comparison to neutral faces and whether this improvement would be reflected during encoding or retrieval. Caucasian and African American faces were rated as angry or neutral by a separate pool of Caucasian participants. Caucasian and African/African American participants in the old-new task studied the faces rated as most angry or neutral and later identified them among distractors in the test phase. The Dm, FN400, and parietal old-new effect were recorded during the study and test phase for Caucasian participants. Anger did not improve other-race face memory in behavior for either race of participants. For Caucasian participants, activation increased during retrieval of previously studied angry Caucasian faces, which indicates more detailed memory retrieval of same-race as compared to other-race angry faces. This is evidence that experience with same-race faces and not stereotypes of other-race faces influences the other-race effect during memory retrieval.

Recognising other-race faces is more effortful: The effect of individuation instructions on encoding-related ERP Dm effects

Humans are better at recognising faces from their own vs. another ethnic background. Socio-cognitive theories of this own-race bias (ORB) propose that reduced recognition of other-race faces results from less motivation to attend to individuating information during encoding. Accordingly, individuation instructions that explain the phenomenon and instruct participants to attend to other-race faces during learning attenuate or eliminate the ORB. However, it is still unclear how exactly such instructions affect other-race face processing. We addressed this question by investigating encoding-related event-related brain potentials, contrasting neural activity of subsequently remembered and forgotten items (Dm effects). In line with socio-cognitive accounts, individuation instructions reduced the ORB. Critically, instructions increased Dm effects for other-race faces, suggesting that more processing resources were allocated to these faces during encoding. Thus, compensating for reduced experience with other-race faces is possible to some extent, but additional resources are needed to decrease difficulties resulting from a lack of perceptual expertise.