Holistic image processing is tied to expertise and is characteristic of face and body processing by adults. Infants process faces holistically, but it is unknown whether infants process body information holistically. In the present study, we examined whether infants discriminate changes in body posture holistically. Body posture is an important nonverbal cue that signals emotion, intention, and goals of others even from a distance. In the current study, infants were tested for discrimination between body postures that differ in limb orientations in three conditions: in the context of the whole body, with just the limbs that change orientation, or with the limbs in the context of scrambled body parts. Nine-month olds discriminated between whole body postures, but failed in the isolated parts and scrambled body conditions, indicating that they use holistic processes to discriminate body information. In contrast, 3.5-month olds failed to discriminate between whole body postures, therefore no conclusion can be drawn about their ability to process bodies holistically. These results indicate that infants process body information holistically during the first year of life, but there are developmental changes in the processing of body information from 3.5 to 9 months of age.

Many important questions remain unanswered regarding how we recognize faces. Methodological inconsistencies have contributed to confusion regarding these questions, especially those surrounding three purported face processing mechanisms—featural, configural, and holistic—and the extent to which each play a role in face recognition. The work presented here aims to 1) empirically test the assumption that several face recognition tasks index the same underlying construct(s), and 2) contribute data to a number of ongoing debates concerning the reliability and validity of various methods for assessing integrative (i.e., holistic and/or configural) aspects of face processing. Experiment 1 tested the assumption that various tasks purporting to measure integrative face processing index the same construct(s). It is important to test this assumption because if these tasks are in fact measuring different things, then researchers should cease interpreting them as interchangeable measures. Using a within-subjects design (N = 223) we compared performance—as reflected by accuracy and reaction time measures, as well as two types of difference scores—across four of the most commonly used integrative face processing tasks: The Partial Composite Face Effect Task, the Face Inversion Effect Task, the Part Whole Effect Task, and the Configural/Featural Difference Detection Task. Analyses showed that within-task correlations were much stronger than those between-tasks. This suggests that the four conditions within each task are measuring something in common; In contrast, low correlations across tasks suggest that each is measuring something unique. This in turn suggests these tasks should not be seen as assessing the same integrative face-processing construct. Exploratory factor analyses corroborated the correlation data, finding that performance on most conditions loaded onto a single factor in unrotated solutions, but onto separate factors in direct oblimin-rotated solutions. In Experiment 2, we investigated the question of whether integrative face processing performance is related to face recognition ability. We did this by assessing the degree to which results from four widely-used integrative face processing tasks correlate with a measure of general face recognition ability, The Cambridge Face Memory Test (CFMT). The four integrative processing tasks used in this study only partly overlapped those from in Experiment 1. They were: The Complete Composite Face Effect Task, the Partial Composite Face Effect Task, the Part Whole Effect Task, and the Configural/Featural Difference Detection Task. As with Experiment 1, we used a within-subjects design (N = 260) and analyzed a variety of performance variables across these tasks. Analyses demonstrated low to moderate positive correlations between performance on the task conditions and performance on the CFMT. This suggests that the constructs the tasks reflect do contribute to face recognition ability to a modest degree. These analyses also replicated parts of Experiment 1, showing weak correlations between tasks. Also similar to Experiment 1, factor analyses generally revealed task conditions loading onto a common first factor in the unrotated factor matrix, but loading separately in the rotated factor solution. In addition to providing evidence regarding the nature of integrative face processing tasks, the data presented here speak to a number of other questions in this domain. For instance, they contribute to the debate regarding which kinds of difference scores (subtraction-based or regression-based) are more reliable, as well as the reliability of the various tasks used to investigate integrative face processing. In addition, the data inform the debate over whether the Complete or the Partial version of the Composite Face Effect Task is the superior measure of integrative face processing. In summary, the studies presented here indicate that the previous literature in face recognition needs to be interpreted with care, with an eye to differences in methodology and the problems of low measurement reliability. The various methods used to investigate integrative face processing are not assessing the same thing and cannot be taken as reflecting the same underlying construct.

No description available.

<p>Holistic processing has been deemed a crucial part of human face processing. There are three tasks that are indexes of holistic processing and each is used by many researchers for the purposes of demonstrating that either their participants have intact holistic processing or that holistic processing is impaired or missing. The tasks that demonstrate holistic processing are the face inversion, composite face, and the whole-part tasks. In this dissertation, I evaluate the hypothesis that holistic processing is important for face identification. A secondary hypothesis that is evaluated is whether the three indexes of holistic processing are related and whether they are tapping the same underlying process. Chapter 2 tests the first hypothesis in a large group of young adults and shows that the composite face effect (an index of holistic processing) is not related to accuracy on two identification tasks. Chapter 3 tested both hypotheses and showed that none of the holistic indexes are related to one another and they are unrelated to face identification accuracy. In Chapter 4, a large group of older adults are tested on the composite face task and a face identification task, similar to Experiment 2 from Chapter 2. Unlike the results for young adults, older adults show a significant positive correlation between the composite face effect and identification accuracy even though older adults perform worse on the identification task.</p> / Doctor of Philosophy (PhD)

Igenkänning av ansikten har främst undersökts i form av korttidsretention. Via sådan forskning har det kunnat påvisas att människor generellt har en bättre förmåga till igenkänning av ansikten jämfört med visuella stimulus av liknande komplexitet. Det har även påvisats effekter av extraversion och kön på förmågan att känna igen ansikten. Denna studie undersökte långtidsretention av ansikten och detta i relation till extraversion och kön. Utöver detta undersökte studien relationen mellan igenkänning av ansikten och annat visuellt stimulus (hundar). Detta studerades genom en experimentell inomgruppsdesign där deltagarna utförde ett datorbaserat igenkänningstest direkt och 24 timmar efter inlärning. Extraversion mättes med självskattningsformuläret Revised NEO Personality Inventory (NEO-PI R). Studien inkluderade 51 deltagare (31 kvinnor, 19 män, en icke-binär, M = 27.69 år). Resultaten visade en fördel för igenkänning av ansikten, men kunde inte påvisa någon skillnad i nedgång stimulusen emellan. Vidare visade resultaten en signifikant stimulus × kön interaktion, där kvinnor presterade bättre än män på igenkänning av ansikten men inte på igenkänning av hundar. En effekt av extraversion hittades enbart i extremgrupperna på kontinuumet extraversion. Slutligen visade studien att det inte fanns något signifikant samband mellan prestation på igenkänning av hundar och ansikten vid det första testtillfället. I studien diskuteras implikationerna ett holistiskt processande verkar ha på inlärning men inte på minneskonsolidering över tid. Studien belyser också brister i tidigare studier som undersökt extraversion i relation till ansiktsigenkänning och fördjupar sig i eventuella orsaker till uppmätta könsskillnader. / Face-recognition has foremost been studied with a focus on short-term retention. This research has concluded that in general people are a better in recognizing faces in comparison to recognition of stimuli with matching complexity. Studies have also shown that extraversion and sex affect face-recognition ability. This study investigated long-term memory retention of faces in relation to extraversion and sex. In addition, this study explored the relationship between recognition of faces, and another visual stimulus (dogs). This was conducted by using an experimental within-subjects-design in which the participants performed a computer-based recognition-test both immediately after the study phase, as well as 24 hours later. Revised NEO Personality Inventory (NEO-PI R) was used to measure extraversion. The study had 51 participants (31 women, 19 men, one non-binary, M = 27.69 years). The results showed an advantage in recognition of faces but failed to show a difference in decline between stimuli. There was a stimulus × sex interaction, where women showed an advantage compared to men in recognition of faces but not regarding recognition of dogs. Extraversion was shown to have an effect on the performance only when the most and least extraverted was compared. Finally, there was no relationship between face-recognition and recognition of dogs in the short-term retention test. The study highlights shortcomings in earlier studies investigating extraversion in relation to face recognition and discusses possible reasons for the obtained sex differences. The study also discusses whether holistic processing is implicated in learning, but not with respect to long-term memory consolidation.

The face plays an extremely important role in human communication. It enables individual recognition and provides other information about the person, such as social or emotional information. Human psychology has shown that face recognition uses a specific cognitive process called holistic processing. In recent decades, it has been shown to play an important role in animal communication as well. In the first part of my thesis, I tested whether changing the uniform configuration of a bird's face would affect the ability of the red-backed shrike (Lanius collurio) to recognize a potential predator. Due to unfavourable conditions in both breeding seasons when the experiments were conducted, no firm conclusions can be drawn from the results. They only suggest that the shrike perceives the configuration changes. An essential characteristic of all predators is their size, which affects the ability of prey to defend themselves. Several studies have already found that birds discriminate between different predators of different sizes. In the second part of my thesis, I evaluated experiments in which shrikes were exposed to dummies of two predator species with modified size. The shrikes responded with less aggression to the enlarged jays, whereas aggression increased only slightly to the shrunken crows. Thus,...

La zeitgesit contemporaine sur la reconnaissance des visages suggère que le processus de reconnaissance reposerait essentiellement sur le traitement des distances entre les attributs internes du visage. Il est toutefois surprenant de noter que cette hypothèse n’a jamais été évaluée directement dans la littérature. Pour ce faire, 515 photographies de visages ont été annotées afin d’évaluer l’information véhiculée par de telles distances. Les résultats obtenus suggèrent que les études précédentes ayant utilisé des modifications de ces distances ont présenté 4 fois plus d’informations que les distances inter-attributs du monde réel. De plus, il semblerait que les observateurs humains utilisent difficilement les distances inter-attributs issues de visages réels pour reconnaître leurs semblables à plusieurs distances de visionnement (pourcentage correct maximal de 65%). Qui plus est, la performance des observateurs est presque parfaitement restaurée lorsque l’information des distances inter-attributs n’est pas utilisable mais que les observateurs peuvent utiliser les autres sources d’information de visages réels. Nous concluons que des indices faciaux autre que les distances inter-attributs tel que la forme des attributs et les propriétés de la peau véhiculent l’information utilisée par le système visuel pour opérer la reconnaissance des visages. / According to an influential view, based on studies of development and of the face inversion effect, human face recognition relies mainly on the treatment of the distances among internal facial features. However, there is surprisingly little evidence supporting this claim. Here, we first use a sample of 515 face photographs to estimate the face recognition information available in interattribute distances. We demonstrate that previous studies of interattribute distances generated faces that exaggerated 4 times this information compared to real-world faces. When interattribute distances are sampled from a real-world distribution, we show that human observers recognize faces poorly across a broad range of viewing distances (with a maximum accuracy of 65%). In contrast, recognition performance is restored when observers only use facial cues of real-world faces other than interattribute distances. We conclude that facial cues other than interattribute distances such as attribute shapes and skin properties are the dominant information of face recognition mechanisms.

La zeitgesit contemporaine sur la reconnaissance des visages suggère que le processus de reconnaissance reposerait essentiellement sur le traitement des distances entre les attributs internes du visage. Il est toutefois surprenant de noter que cette hypothèse n’a jamais été évaluée directement dans la littérature. Pour ce faire, 515 photographies de visages ont été annotées afin d’évaluer l’information véhiculée par de telles distances. Les résultats obtenus suggèrent que les études précédentes ayant utilisé des modifications de ces distances ont présenté 4 fois plus d’informations que les distances inter-attributs du monde réel. De plus, il semblerait que les observateurs humains utilisent difficilement les distances inter-attributs issues de visages réels pour reconnaître leurs semblables à plusieurs distances de visionnement (pourcentage correct maximal de 65%). Qui plus est, la performance des observateurs est presque parfaitement restaurée lorsque l’information des distances inter-attributs n’est pas utilisable mais que les observateurs peuvent utiliser les autres sources d’information de visages réels. Nous concluons que des indices faciaux autre que les distances inter-attributs tel que la forme des attributs et les propriétés de la peau véhiculent l’information utilisée par le système visuel pour opérer la reconnaissance des visages. / According to an influential view, based on studies of development and of the face inversion effect, human face recognition relies mainly on the treatment of the distances among internal facial features. However, there is surprisingly little evidence supporting this claim. Here, we first use a sample of 515 face photographs to estimate the face recognition information available in interattribute distances. We demonstrate that previous studies of interattribute distances generated faces that exaggerated 4 times this information compared to real-world faces. When interattribute distances are sampled from a real-world distribution, we show that human observers recognize faces poorly across a broad range of viewing distances (with a maximum accuracy of 65%). In contrast, recognition performance is restored when observers only use facial cues of real-world faces other than interattribute distances. We conclude that facial cues other than interattribute distances such as attribute shapes and skin properties are the dominant information of face recognition mechanisms.

Informelle Berichte zeigten größere Amplituden der durch Gesichter ausgelösten N170 Komponente im Ereigniskorrelierten Potenzial (EKP) bei asiatischen als bei kaukasischen Probanden. Als mögliche Ursache vermutete ich unterschiedliche Erfahrungen mit logographischen bzw. alphabetischen Schriftsystemen (Schriftsystem-Hypothese) oder die verstärkte Exposition mit unbekannten Gesichtern während der Immersion in eine neue soziale oder ethnische Umgebung (soziale Immersions-Hypothese). Zur Überprüfung dieser Hypothesen führte ich zwei kulturvergleichende Studien mit Erwachsenen bzw. Kindern durch. In Studie 1 untersuchte ich einheimische Chinesen und nicht-chinesische Auswärtige in Hongkong und deutsche Einheimische und chinesische Auswärtige in Berlin. Die Auswärtigen an beiden Orten zeigten größere N170 Amplituden auf Gesichter als die Einheimischen. Außerdem zeigten Deutsche, die erst kurze Zeit in Berlin lebten ähnliche Amplituden wie langjährige Einheimische. Insgesamt unterstützt Studie 1 die soziale Immersions-Hypothese, dass die Immersion in eine neue ethnische Umgebung zu einer Vergrößerung der N170 führt. Studie 2 untersuchte die Schriftsystem-Hypothese bei chinesischen und deutschen Erstlesern am Ende der ersten oder zu Beginn des zweiten Schuljahres an ihrem jeweiligen Heimatort. Die Ergebnisse unterstützen die Schriftsystem-Hypothese, dass chinesische Kinder eine größere N170 auf Gesichter zeigen als deutsche. Insgesamt konnte die vorliegende Dissertation zwei neue Einfluss-Faktoren auf das Gesichterverarbeitungs-System nachweisen, das erworbene Schriftsystem (logographische versus alphabetisch) und die Erfahrung sozialer Immersion in eine neue ethnische Umgebung. Diese Effekte zu ganz unterschiedlichen Zeitpunkten der Entwicklung (Kindheit vs. junges Erwachsenen-Alter) zeigen, dass das Gesichterverarbeitungs-System über lange Zeit seine Plastizität behält. / Informal reports have shown larger face-elicited N170 component of event-related potential (ERP) in Asians than Caucasians participants. I proposed that different experience with logographic versus alphabetic scripts (script system hypothesis) or by exposure to abundant novel faces during the immersion into a new social and/or ethnic environment (social immersion hypothesis) as a possible cause. To test these hypotheses, I conducted two cross-cultural ERP studies with adults and Children. In Study 1, I examined Chinese locals and non-Chinese foreigners in Hongkong, and German locals and Chinese foreigners in Berlin. It turned out that the foreigners in both locations showed larger N170 amplitudes to faces than the locals. In addition, Germans who had only lived in Berlin for a short time showed similar face N170 amplitudes as long-term Berlin residents. In sum, Study 1 supports the social immersion hypothesis that immersing into a new ethnic environment drives an increase of face N170. Study 2 investigated the scripts system hypothesis in Chinese and German early readers assessed at the end of the first-grade or at the beginning of the second grade in their respective home towns. The findings support the script system hypothesis that Chinese children showed larger face N170 amplitudes than German children. Overall, the present thesis demonstrated two new influencing factors on the face processing system, the acquired script system (logographic vs. alphabetic) and the social immersion experience in a new ethnic environment. More specifically, learning to read a visually complex logographic Chinese script or immersing into an other-ethnic social environment facilitates early perceptual processing of faces. These effects acquired at different stages of development (early childhood versus young adulthood) show that the face processing system retains its plasticity over a long period of time.