The composite face illusion: A whole window into our understanding of holistic face perception

Two identical top halves of a face are perceived as being different when their bottom halves belong to different faces, showing that the parts of a face cannot be perceived independently from the whole face. When this visual illusion is inserted in a matching task, observers make more mistakes and/or are slower at matching identical top face halves aligned with different bottom halves than when the bottom halves are spatially offset: The composite face effect. This composite face paradigm has been used in more than 60 studies that have provided information about the specificity and nature of perceptual integration between facial parts (“holistic face perception”), the impairment of this process in acquired prosopagnosia, its developmental course, temporal dynamics, and neural basis. Following a review of the main contributions made with the paradigm, I explain its rationale and strengths, and discuss its methodological parameters, making a number of proposals for its optimal use and refinement in order to improve our understanding of holistic face perception. Finally, I explain how this standard composite face paradigm is fundamentally different than the application to facial parts of a congruency/interference paradigm that has a long tradition in experimental psychology since Stroop (1935), and which was originally developed to measure attentional and response interference between different representations rather than perceptual integration. Moreover, a version of this congruency/interference paradigm used extensively over the past years with composite faces lacks a baseline measure and has decisional, attentional, and stimulus confounds, making the findings of these studies impossible to interpret in terms of holistic perception. I conclude by encouraging researchers in this field to concentrate fully on the standard composite face paradigm, gaze contingency, and other behavioural measures that can help us take one of the most important challenges of visual perception research: Understanding the neural mechanisms of holistic face perception.     

Holistic face perception: Mind the gap!

The most widely used measurement of holistic face perception, the composite face effect (CFE), is challenged by two apparently contradictory goals: having a defined face part (i.e., the top half), and yet perceiving the face as an integrated unit (i.e., holistically). Here, we investigated the impact of a small gap between top and bottom face halves in the standard composite face paradigm, requiring matching of sequentially presented top face halves. In Experiment 1, the CFE was larger for no-gap than gap stimuli overall, but not for participants who were presented with gap stimuli first, suggesting that the area of the top face half was unknown without a gap. This was confirmed in Experiment 2, in which these two stimulus sets were mixed up: the gap stimuli thus provided information about the area of a top face half and the magnitude of the CFE did not differ between stimulus sets. These observations indicate that the CFE might be artificially inflated in the absence of a stimulus cue that objectively defines a border between the face halves. Finally, in Experiment 3, observers were asked to determine which of two simultaneously presented faces was the composite face. Perceptual judgements for no-gap stimuli approached ceiling; however, with a gap, participants were almost unable to distinguish the composite face from a veridical face. This effect was not only due to low-level segmentation cues at the border of no-gap face halves, because stimulus inversion decreased performance in both conditions. This result indicates that the two halves of different faces may be integrated more naturally with a small gap that eliminates an enhanced contrast border. Collectively, these observations suggest that a small gap between face halves provides an objective definition of the face half to match and is beneficial for valid measurement of the behavioural CFE.     

Multimodal Perception of Reachability Expressed Through Locomotion

We investigated the information that supports perception of whether an object is within reach using a locomotor task. Participants adjusted their own position relative to a fixed target by stepping or by propelling a wheelchair until they judged it to be within reach. The to-be-reached object was presented in virtual reality. The display of the target was driven in real time as a function of the observer's movement, thus depicting a stationary virtual object at a definite distance only through the relation across optical and nonoptical patterns of stimulation. We asked participants to judge the distance they could reach with their unaided hand or when holding a rod that extended their effective reach. They could see neither their body nor the rod thereby limiting available visual information about “reachability.” As expected, our results showed that despite the limited information that was available, participants' locomotor adjustments were influenced by (a) their simulated distance from the target, (b) their arm length, and (c) the presence or absence of the rod. The type of motion (stepping or wheelchair) had little influence. However, judgment accuracy was influenced by participants' initial simulated distance from the target. We compare the performance obtained in our locomotor judgment task with previous studies that have used different methods for measuring perceived reaching-ability. We discuss perceptual information that could have supported performance within the framework of the global array.     

Adult Attachment Styles and Psychological Disease: Examining the Mediating Role of Personality Traits

ABSTRACT

The aim of the present study was to examine differences in anxiety and depression related to differences in attachment models of the self and of others and whether personality traits mediate this relationship. The authors assessed attachment styles, anxiety, depression, and personality traits among 274 adult volunteers. Participants were classified into 4 attachment groups (secure, preoccupied, fearful, and dismissing–avoidant) according to K. Bartholomew's (1990) Bartholomew, K. 1990. Avoidance of intimacy: An attachment perspective. Journal of Social and Personal Relationships, 7: 147–178. [Crossref], [Web of Science ®] , [Google Scholar] model. The present authors found significant differences among attachment groups on anxiety and depressive symptoms with attachment styles involving a negative self-model showing higher scores than attachment styles characterized by a positive self-model. The authors also found that differences between attachment styles in anxiety and depression remained significant when personality factors related to attachment prototypes were entered as covariates. Results indicate that secure attachment in adults was associated with better mental health, while insecure attachment styles characterized by negative thinking about the self were associated with higher depression and anxiety scores. Our findings seem to evidence that attachment and personality are only partly overlapping and that attachment cannot be considered as redundant with personality in the explanation of psychological disease.     

Index to Volume 112

For various nonnormal distributions, the power of the Student t test can be increased if continuous measures are transformed to ranks before the test is performed. The power of the test can also be increased almost as much and, even more for some distributions, if measures are replaced by dichotomous variables with the values 0 and 1, instead of ranks. Similarly, the power of a significance test of correlation can be increased if scores are transformed to ranks, that is, with the use of the Spearman rank correlation method. Power can also be increased almost as much and in some cases even more if dichotomous variables are introduced, that is, if the phi coefficient is used as a measure of correlation.     

I suffer more from your pain when you act like me: Being imitated enhances affective responses to seeing someone else in pain

Social–psychological research has suggested that being imitated changes the way that we experience others: We like someone who imitates us more, and the interaction with this person runs more smoothly. Whether being imitated also affects basic social reactions, such as empathy for pain, is an open question. Empathy for pain refers to the observation that perceiving another person in pain results in pain-related brain activation in the observer. The aim of the present study was to combine the two lines of research, to investigate whether being imitated can influence empathy for pain. To this end, we developed an experimental approach combining an imitation task with a pain perception task. Subjective reports, as well as physiological responses, indicated that being imitated enhances affective responses to seeing someone else in pain. Furthermore, using rubber hand illusion measures, we provided evidence for the role of shared representations in the sensory and motor domains as a core underlying mechanism. In this way, our study integrated social–psychological research on being imitated with cognitive research on empathy for pain. This has broad implications, since imitation plays a crucial role in our daily social interactions, and our study provides insights into a basic cognitive mechanism that might underlie these social situations.     

Exploring the validity of scores from the Rosenberg Self-Esteem Scale (RSES) in Burundi: A multi-strategy approach

The present study aimed to validate the Rosenberg Self-Esteem Scale (RSES) in Burundi, through a multi-strategy approach used in cross-cultural studies. Respondents were 906 health workers (men = 56%; caregivers 60%). They responded to a bilingual version of RSES. We utilised Confirmatory Factorial Analysis (CFA) with structural equation modelling and a back translation test to explore the structure of the RSES and the reliability of scores from the scale. Data from an independent sample were analysed for the reliability of scores assessment. CFA results suggested that the global RSES factor was likely contaminated by a method-effect; mainly associated with negatively worded items. Internal consistencies and a back-translation test demonstrated that the negatively worded items were unsuitable in this context. The independent sample study confirmed poor reliability and internal consistency of scores for both alternative language versions of the RSES. Our data suggested that an overall cultural effect, rather than a merely specific language effect, may undermine the cross-cultural transportability of the Western scale.     

The influence of contour fragmentation on recognition memory: an event-related potential study

The present study was carried out to examine how the event-related potentials to fragmentation predict recognition success. Stimuli were abstract meaningless figures that were either complete or fragmented to various extents but still recoverable. Stimuli were first encoded as part of a symmetry discrimination task. In a subsequent recognition phase, encoded stimuli were presented complete along with never presented stimuli and participants performed an old/new discrimination task. Fragmentation stimuli elicited more negative ERPs than complete figures over the frontal, central and parietal areas between 180 and 260 ms, and over the occipito-temporal areas between 220 and 340 ms. Only this latter effect was modulated as a function of whether stimuli were recognized or not during the recognition phase of the memory test. More specifically, the effect occurred for stimuli that were later forgotten and was absent for stimuli that were later recognized. This ERP to fragmentation, the occipito-temporal N(frag), possibly reflects the brain response to encoding difficulty, and is thus predictive of recognition performance.