91 research outputs found
Breaking face processing tasks apart to improve their predictive value in the real world: A comment on Ramon, Bobak, and White (2019).
peer reviewedIn this commentary, I will expand on three aspects suggested by Ramon et al. (2019, British Journal of Psychology, 110, 461) to improve the predictive value of laboratory-based tasks in real-world applications. There are potential benefits that may arise from three interrelated considerations, particularly in terms of predicting agents' susceptibility to errors in operational settings. The first is a proposal to conduct a detailed examination of performance on face processing tests rather than only analysing overall accuracy scores. The second involves considering non-face-related cognitive and meta-cognitive sub-processes involved in face processing tasks. The third highlights the contribution of superior recognisers in creating challenging tests that simulate difficult real-world situations
The illusory perception of distinctiveness in familiar faces
peer reviewedAn illusion of distinctiveness forfaces is described that manifests asa positive association between perceived familiarity and perceived distinctiveness. This association seems partly rooted in intrinsic facial characteristics but is boosted by actual exposure to faces.Suchillusioncould impederesearch onfamiliar faceswhere distinctiveness is manipulated or controlled and researchers will need to find ways around it
THE VISUAL PROCESSING OF SELF-REFERENTIAL STIMULI: DO WE PROCESS OUR OWN FACE DIFFERENTLY FROM OTHER FACES?
Lorsque nous pensons à nous-mêmes, à toutes les caractéristiques physiques ou
psychologiques qui nous définissent, à tous les objets que nous possédons, nous avons
l’impression qu’ils ont un statut bien particulier dans notre esprit, qu’ils sont spéciaux pour
nous. Notre propre visage est certainement parmi l’une des plus uniques et distinctives de
toutes ces informations autoréférentielles. Dans ce travail, nous nous sommes penchés sur
les spécificités du traitement visuel du propre visage.
Dans un premier chapitre théorique, nous avons questionné la possibilité d’utiliser le
traitement du propre visage comme un indice de conscience de soi (voir Chapitre 1).
Ensuite, nous avons passé en revue les différentes études existantes qui concernaient la
spécificité du propre visage ou d’autres informations autoréférentielles (voir Chapitre 2).
Suite à cette revue de la littérature, il est apparu que l’intuition selon laquelle notre propre
visage est un stimulus spécial n’avait pas pu être confirmée unanimement par les études qui
nous précédaient.
Ce travail ambitionnait donc d’évaluer empiriquement dans quelle mesure notre propre
visage est traité par le système cognitif de façon différente des autres visages que nous
rencontrons. Nous avons tenté de répondre à cette question selon trois angles différents.
Tout d’abord, nous nous sommes intéressés à la précision de la représentation de notre
propre visage en mémoire. Pour cela, nous avons utilisé dans notre première étude une
méthode psychophysique permettant de déterminer dans quelle mesure nous sommes
capables de détecter des modifications fines apportées à des photographies de notre propre
visage (voir Chapitre 4). Ensuite, nous avons examiné si la reconnaissance de notre propre
visage, mais aussi celle de notre propre corps, sont sous-tendues par des zones cérébrales
spécifiques. A cette fin, au cours d’une seconde étude, nous avons utilisé l’imagerie par
résonance magnétique fonctionnelle (IRMf, voir Chapitre 5). Enfin, nous avons testé si le
propre visage est particulièrement apte à capturer ou à retenir notre attention lorsqu’il est
présenté de façon inopportune alors que nous sommes occupés à réaliser une tâche sans
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rapport (voir Chapitres 6, 7 et 8). Pour ce faire, nous avons eu recours, dans une série de
trois études, à différents paradigmes attentionnels : un paradigme de jugement de parité, un
paradigme de cécité attentionnelle, et un paradigme de recherche visuel lors duquel nous
avons procédé à l’enregistrement des mouvements oculaires des participants.
Tout au long de ce travail, nous avons adopté une approche visant à différencier les effets
d’autoréférence de simples effets de familiarité. Pour ce faire, dans toutes nos études, nous
avons comparé les réponses obtenues lors de la présentation du propre visage du
participant à celles obtenues lors de la présentation du visage d’une personne hautement
familière pour le participant (un ami ou un collègue du même groupe d’âge et du même
sexe). Par ailleurs, dans les études attentionnelles, les réponses subséquentes à la
présentation de ces deux visages familiers étaient également comparées à celles obtenues
suite à l’apparition de visages de personnes inconnues. En somme, si les performances
obtenues sur le propre visage et le visage très familier différaient, nous pourrions penser
que ces différences sont dues à l’aspect autoréférentiel du propre visage. Par contre, si les
performances ne différaient pas entre le propre visage et l’autre visage très familier mais
que ces deux visages se distinguaient des visages inconnus, nous pourrions supposer que
nous sommes face à de simples effets de familiarité.
La première étude psychophysique a montré que la représentation que nous avons en
mémoire de notre propre visage est très précise. Cette précision est seulement limitée par
les capacités de discrimination perceptive de notre système visuel. Cependant, il en était de
même pour le visage d’une autre personne hautement familière. De ce point de vue, il ne
semble donc pas que notre propre visage soit spécial. Néanmoins, il semblerait que cette
représentation soit sous-tendue par des substrats cérébraux spécifiques, comme indiqué par
notre seconde étude en IRMf. Cette étude a aussi montré que notre propre corps serait
également traité par des régions cérébrales spécifiques. De plus, certaines régions seraient
dédiées au traitement abstrait de notre propre apparence physique puisqu’elles étaient
impliquées indépendamment du type de matériel présenté (visage ou corps). Enfin, nous
avons montré, grâce aux trois études attentionnelles, que le propre visage n’est pas un
distracteur exceptionnel par rapport à d’autres visages familiers. En effet, le propre visage
ne semble pas capturer l’attention de façon automatique. Il semblerait que le propre visage
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bénéficie simplement d’une allocation de l’attention préférentielle par rapport à des visages
inconnus. En d’autres termes, l’allocation de l’attention au propre visage est sujette Ă
diverses contraintes (par exemple sa localisation spatiale) et il semblerait que l’attention soit
nécessaire pour identifier le propre visage en tant que tel.
Cet ensemble de résultats est discuté dans un dernier chapitre (voir Chapitre 9) où nous
tentons de mettre les données provenant des trois perspectives différentes (représentation
en mémoire, substrats cérébraux et propriétés attentionnelles relatifs au propre visage) en
rapport. De plus, la possibilité d’utiliser le propre visage comme outil d’étude de la
conscience de soi ou de différents processus cognitifs (reconnaissance ou attention visuelle)
est brièvement passée en revue
An inconvenient association between familiarity and distinctiveness ratings of familiar faces
peer reviewedNew ratings data suggest that the more a famous face is judged familiar, the more it is judged distinctive, that is different from other faces. The same ratings obtained on unfamiliar faces do not show the same positive association. High distinctiveness ratings on celebrities might thus reflect an illusion of distinctiveness—a subjective impression that does not match the objective distinctiveness of a given face’s features. Such illusion, making objective distinctiveness ratings difficult to obtain for faces that are widely known, could be problematic for building well-controlled materials to study familiar face recognition, the impact of distinctiveness itself or individual differences in face recognition abilities. To objectify this phenomenon and test if it can be mitigated, we examined the links between familiarity and distinctiveness ratings obtained from full headshots of celebrities and between familiarity and compound distinctiveness ratings calculated from ratings on four different isolated facial parts. Isolating facial parts is known to disrupt facial recognition, and so ratings of isolated parts should be less influenced by familiarity than ratings of headshots. We found that the association between familiarity and distinctiveness was stronger than between familiarity and compound distinctiveness, both at the individual participant level and at the face item level. The eyes and external features were the most distinctive while the mouth and the nose areas were the least. We will discuss the implications of this illusion of distinctiveness for future research on familiar face recognition and how it might further our understanding of information contained in facial representations
Angry faces hold the eyes
peer reviewedEfficient processing of complex social and biological stimuli associated with threat is crucial for survival. Previous studies have suggested that threatening stimuli such as angry faces not only capture visual attention, but also delay the disengagement of attention from their location. However, in the previous studies disengagement of attention was measured indirectly and was inferred on the basis of delayed manual responses. The present study employed a novel paradigm that allows to directly examine the delayed disengagement hypothesis by measuring the time it takes to disengage the eyes from threatening stimuli. The results showed that participants were indeed slower to make an eye movement away from an angry face presented at fixation than from either a neutral or a happy face. This finding provides converging support that the delay in disengagement of attention is an important component of processing threatening information
Faces are special, but facial expressions aren't: Insights from an oculomotor capture paradigm.
peer reviewedWe compared the ability of angry and neutral faces to drive oculomotor behaviour as a test of the widespread claim that emotional information is automatically prioritized when competing for attention. Participants were required to make a saccade to a colour singleton; photos of angry or neutral faces appeared amongst other objects within the array, and were completely irrelevant for the task. Eye-tracking measures indicate that faces drive oculomotor behaviour in a bottom-up fashion; however, angry faces are no more likely to capture the eyes than neutral faces are. Saccade latencies suggest that capture occurrs via reflexive saccades and that the outcome of competition between salient items (colour singletons and faces) may be subject to fluctuations in attentional control. Indeed, although angry and neutral faces captured the eyes reflexively on a portion of trials, participants successfully maintained goal-relevant oculomotor behaviour on a majority of trials. We outline potential cognitive and brain mechanisms underlying oculomotor capture by faces
Strategic learning of people's names as a function of expected utility in young and old adults
People’s names are notoriously challenging to learn at all ages, more so than semantic information. Because people are somewhat aware of memory limitations and of their own difficulty of learning names, they might spontaneously use cost-efficient encoding strategies whereby they devote more memory resources to the names of people that are most likely to be useful to learn than others. To test this hypothesis, we told young and older participants that they would judge excerpts of a new TV series about a group of twelve musicians and that they could first review information about the characters to facilitate the upcoming viewing, which consisted of face-name-instrument triplets. Further, the probability of appearance of each character was specified via an importance label (main or secondary characters, bit parts). Participants then performed a surprise cued recall test and recalled names, instruments and importance labels associated with pictures. Unsurprisingly, young adults had better memory performance than older ones and semantic information was better recalled than names. In line with a cost-efficient encoding strategy, participants in both groups recalled names and semantic information of the most important characters better, suggesting they had prioritised encoding information about those characters to the detriment of others. Interestingly, there were individual differences in spontaneous encoding strategies used. People who reported using cost-efficient strategies had better memory performance than others and individuals who remembered more semantic information about main characters than about bit parts also did so with names, suggesting that cost-efficient strategies improves the encoding of two types of information
Strategic learning of people's names as a function of expected utility in young and older adults.
peer reviewedPeople's names are challenging to learn at all ages. Because people somewhat know this, they might spontaneously use cost-efficient encoding strategies and devote more resources to learn names that are most likely to be useful. To test this hypothesis, we created a pseudo-incidental learning situation in which young and older participants were exposed to 12 characters from a TV show and reviewed face-name-instrument triplets. Characters' probability of appearance was specified via importance labels (main or secondary characters, bit parts). A surprised cued recall test showed that young adults performed better than older ones, and that semantic information was better recalled than names. Consistent with cost-efficient encoding strategies, participants in both groups recalled names and semantic information about most important characters better. Interestingly, there were large individual differences: people who reported using cost-efficient strategies performed better. At the individual level, memory advantages for most important characters' names and semantic information correlated
Fleeting reliability in the dot-probe task.
In a dot-probe task, two cues-one emotional and one neutral-are followed by a probe in one of their locations. Faster responses to probes co-located with the emotional stimulus are taken as evidence of attentional bias. Several studies indicate that such attentional bias measures have poor reliability, even though ERP studies show that people reliably attend to the emotional stimulus. This inconsistency might arise because the emotional stimulus captures attention briefly (as indicated by ERP), but cues appear for long enough that attention can be redistributed before the probe onset, causing RT measures of bias to vary across trials. We tested this hypothesis by manipulating SOA (stimulus onset asynchrony between onset of the cues and onset of the probe) in a dot-probe task using angry and neutral faces. Across three experiments, the internal reliability of behavioural biases was significantly greater than zero when probes followed faces by 100Â ms, but not when the SOA was 300, 500, or 900Â ms. Thus, the initial capture of attention shows some level of consistency, but this diminishes quickly. Even at the shortest SOA internal reliability estimates were poor, and not sufficient to justify the use of the task as an index of individual differences in attentional bias
A cost-efficient face learning mechanism: The impact of stability in appearance on the resolution of facial representations
The way faces become familiar and what information is represented as familiarity develops has puzzled researchers in the field of human face recognition for decades. In this paper, we propose a cost-efficient mechanism of face learning to describe how facial representations form over time and that explains why recognition errors occur. Encoding of diagnostic facial information would follow a coarse-to-fine trajectory, modulated by the intrinsic stability in individual faces’ appearance. In four experiments, we draw on a robust and ecological method using a proxy of exposure to famous faces in the real world to test hypotheses generated by the model and we manipulate test images to probe the nature of facial representations. We consistently show that stable facial appearances help create more reliable representation in early stages of familiarisation but that their resolution remains relatively low and therefore less discriminative over time. In contrast, variations in appearance hinder recognition at first but encourage refinement of representations with further exposure. Consistent with the cost-efficient face learning mechanism we propose, facial representations built on a foundation of large-scale coarse information. When coarse information loses its diagnostic value through the experience of variations across encounters, facial details and their spatial relationships receive additional representational weights
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