Importance of the inverted control in measuring holistic face processing with the composite effect and part-whole effect

Holistic coding for faces is shown in several illusions that demonstrate integration of the percept across the entire face. The illusions occur upright but, crucially, not inverted. Converting the illusions into experimental tasks that measure their strength - and thus index degree of holistic coding - is often considered straightforward yet in fact relies on a hidden assumption, namely that there is no contribution to the experimental measure from secondary cognitive factors. For the composite effect, a relevant secondary factor is size of the spotlight of visuospatial attention.The composite task assumes this spotlight can be easily restricted to the target half (e.g., top-half) of the compound face stimulus. Yet, if this assumption were not true then a large spotlight, in the absence of holistic perception, could produce a false composite effect, present even for inverted faces and contributing partially to the score for upright faces.We reviewevidence that various factors can influence spotlight size: race/culture (Asians often prefer a more global distribution of attention than Caucasians); sex (females can be more global); appearance of the join or gap between face halves; and location of the eyes, which typically attract attention. Results from five experiments then show inverted faces can sometimes produce large false composite effects, and imply that whether this happens or not depends on complex interactions between causal factors. We also report, for both identity and expression, that only top-half face targets (containing eyes) produce valid composite measures. A sixth experiment demonstrates an example of a false inverted part-whole effect, where encoding-specificity is the secondary cognitive factor.We conclude the inverted face control should be tested in all composite and part-whole studies, and an effect for upright faces should be interpreted as a pure measure of holistic processing only when the experimental design produces no effect inverted. This Document is Protected by copyright and was first published by Frontiers. All rights reserved. it is reproduced with permissio

No own-race advantage for holistic processing in Chinese participants

Open Access JournalPoster presentations - Face perception: High-level features: 56.304This journal issue is the 2011 meeting abstractsRecent evidence suggests that stronger holistic processing of own-race faces may underlie the well-established own-race advantage for face memory. Across a number of studies Caucasian participants have demonstrated significantly larger holistic processing effects for Caucasian over Asian faces. However, Asian participants have shown a consistently different pattern: similar sized effects for both Asian and Caucasian faces. Here, Experiment 1 replicated these previous findings using Tanaka & Farah?s (1993) part-whole task. Caucasian Australians displayed a significantly larger whole face advantage for Caucasian than Asian faces, while Hong Kong Chinese showed no race-of-face differences in holistic processing. Additionally, we included an inverted face condition to investigate the possibility that results for Asian participants reflect a domain-general global processing bias. Results suggest that Asian participants, unlike Caucasian participants, use face-specific holistic mechanisms to process both own- and other-race upright faces. Experiment 2 used the part-whole task in conjunction with Palermo & Rhodes? (2002) flanker task. In the study phase of each trial the part-whole target was flanked by two faces. Participants performed an across-viewpoint identity-matching task (same/different) on the flanker faces while simultaneously encoding the central target. The presence of holistic processing for the flanker task is argued to disrupt holistic processing of the targets. For Caucasian participants holistic processing for own-race targets was reduced only when the flanker faces were Caucasian. For Asian participants both Asian and Caucasian flankers interfered with holistic processing for own-race targets, however no reduction in holistic processing for other-race targets was observed for either race of flankers. Results for this task again support a difference between Asian and Caucasian participants in holistic processing for other-race face. Together these results suggest that, at least for Asian participants, differences in the strength of holistic processing do not explain differences in memory for own- and other-race faces.link_to_OA_fulltextThe 11th Annual Meeting of the Vision Sciences Society, Naples, FL., 6-11 May 2011. In Journal of Vision, 2011, v. 11 n. 11, article no. 62

Why are face composites difficult to recognize?

Poster Presentation - Face perception: Wholes and parts: 23.522Open Access JournalThis journal issue is the 2011 meeting abstractsThe composite task is widely used in face processing to test issues of holistic processing. In this task, composite faces are formed by taking the top half of one face and pairing it with the bottom half of another. A large body of data has demonstrated that judgments of one half are affected by the identity of the irrelevant half, particularly when the two halves are aligned into the configuration of a normal face, and this interference is thought to be due to mandatory holistic processing of a face. However, very little work has been addressed at understanding the nature of the interference observed in the composite task. We examined this issue by creating composites from faces that were identical except for the spacing of the eyes. In the experiment, Chinese participants viewed Chinese and Caucasian composites (both halves of each face were always the same race), and had to judge whether the top halves of two successive composites were identical or different. The complete design of the composite task was used, so that the composite effect is demonstrated by the top/bottom congruency x alignment interaction. Top (target) halves were always identical except (on half the trials) for the spacing of the eyes; bottom halves were either identical or from different faces. The results showed a significant three-way interaction between congruency, alignment, and orientation, which demonstrated a composite effect but only for aligned, upright faces. This effect was further modified by the significant four-way interaction between congruency, alignment, orientation, and race as our Chinese participants showed a stronger congruency effect for Chinese than Caucasian faces, but again only when they were aligned and upright. These results show that in the composite task, changes in irrelevant face information interfere with the processing of configural relationships within the target region.link_to_OA_fulltextThe 11th Annual Meeting of the Vision Sciences Society, Naples, FL., 6-11 May 2011. In Journal of Vision, 2011, v. 11 n. 11, article no. 66

Importance of the inverted control in measuring holistic face processing with the composite effect and part-whole effect.

Holistic coding for faces is shown in several illusions that demonstrate integration of the percept across the entire face. The illusions occur upright but, crucially, not inverted. Converting the illusions into experimental tasks that measure their strength - and thus index degree of holistic coding - is often considered straightforward yet in fact relies on a hidden assumption, namely that there is no contribution to the experimental measure from secondary cognitive factors. For the composite effect, a relevant secondary factor is size of the "spotlight" of visuospatial attention. The composite task assumes this spotlight can be easily restricted to the target half (e.g., top-half) of the compound face stimulus. Yet, if this assumption were not true then a large spotlight, in the absence of holistic perception, could produce a false composite effect, present even for inverted faces and contributing partially to the score for upright faces. We review evidence that various factors can influence spotlight size: race/culture (Asians often prefer a more global distribution of attention than Caucasians); sex (females can be more global); appearance of the join or gap between face halves; and location of the eyes, which typically attract attention. Results from five experiments then show inverted faces can sometimes produce large false composite effects, and imply that whether this happens or not depends on complex interactions between causal factors. We also report, for both identity and expression, that only top-half face targets (containing eyes) produce valid composite measures. A sixth experiment demonstrates an example of a false inverted part-whole effect, where encoding-specificity is the secondary cognitive factor. We conclude the inverted face control should be tested in all composite and part-whole studies, and an effect for upright faces should be interpreted as a pure measure of holistic processing only when the experimental design produces no effect inverted