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

Abstract

Multiple mechanisms have been suggested to contribute to the other-race effect on face memory, the phenomenon of better memory performance for own-race than other-race faces. Here, two of these mechanisms, increased attention allocation and greater holistic processing during memory encoding for own-race than other-race faces, were tested in two separate experiments. In these experiments event-related potentials were measured during study (the difference due to memory, Dm) and test phase (old/new effects) to examine brain activation related to memory encoding and retrieval, allowing for selective investigations of these memory sub-processes. In Experiment 1, participants studied own-race (Caucasian) and other-race (Chinese) faces under focused or divided attention. In Experiment 2, participants studied own-race (Caucasian) and other-race (African American) faces presented upright or upside down (i.e., inverted). Both experiments showed decreases in memory performance when attention allocation or holistic processing was reduced, but these effects were similar for own-race and other-race faces. Manipulations of holistic processing, but not attention allocation, influenced the neural other-race effects during memory encoding. Inverted own-race faces showed similar neural patterns as upright other-race faces, indicating that when holistic processing of own-race faces was reduced, these faces were encoded similarly as upright other-race faces. No influences of the experimental manipulations on other-race effects during memory retrieval were found. The present study provides the first neural evidence that increased holistic processing during memory encoding contributes to the other-race effect on face memory.

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

“…Lucas, Chiao, and Paller (2011) observed more pronounced Dm effects for own-than for other-race faces, which they interpreted to reflect more elaborate processing of own-race faces. Other studies have focused on the different contributions of familiarity and recollection (see Yonelinas, 2002) to own-and other-race face recognition (e.g., Herzmann, Minor, & Adkins, 2017;Herzmann, Minor, & Curran, 2018;Herzmann, Willenbockel, Tanaka, & Curran, 2011). Overall, these studies suggest that successful memory encoding is more effortful for other-compared to own-race faces.…”

“…For example, Herzmann et al (2011) found recollection-related Dm effects to be more pronounced for other-relative to own-race faces, which was interpreted to reflect less efficient encoding (see also Herzmann et al, 2017). A more recent study further showed that encoding-related activity contributing to Dm effects is sensitive to task difficulty (Herzmann et al, 2018). The authors observed overall more positive amplitudes during a divided attention compared to a focused attention task during encoding, suggesting the recruitment of additional neural resources when the task is more difficult.…”

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

“…If natural, that is default, memory encoding of own-race faces reflects more elaborate processing, we hypothesized that in the whole-face processing task we would find results identical to the patterns of the Dm and old/new effects for own-race faces from our previous studies (Herzmann et al, 2011(Herzmann et al, , 2017(Herzmann et al, , 2018. For own-race faces in the single-feature processing task, we expected to see patterns of the Dm that resembled those of other-race faces in the single-feature processing task because task instructions would prevent the naturally occurring more elaborate processing (Stahl et al, 2010).…”

“…Old/new effects contrast brain activation for old as compared to new items and have been found to show specific ERP components for familiarity, the FN400, and recollection, the parietal old/new effect (Curran, 2000;Rugg & Curran, 2007). The FN400 has been inconsistently observed in face recognition studies (Curran & Hancock, 2007;Herzmann et al, 2011Herzmann et al, , 2017Herzmann et al, , 2018Yovel & Paller, 2004). We therefore focus our review on the parietal old/new effect.…”

“…Given that recollection reflects the retrieval of items with associated details whereas familiarity reflects the retrieval of items alone, the parietal old/new effect has been taken as an indicator of the amount of detail retrieved from memory (Curran, 2000;Rugg & Curran, 2007). We previously found that the parietal old/new effect was larger for own-race than other-race faces (Herzmann et al, 2011(Herzmann et al, , 2017(Herzmann et al, , 2018 and took it as an indication that retrieval of own-race faces is richer and more detailed. This may be a result of the more elaborate encoding during memory encoding as larger parietal old/new effects were seen following deep processing instructions (Marzi & Viggiano, 2010;Stahl et al, 2010), which have been connected to more elaborate encoding (Winograd, 1981).…”