This thesis investigates our sensitivity to social signals from the face, both in health and disease, and explores some of the methodologies employed to measure them. The first set of experiments used forced choice and free naIll1ng paradigms to investigate the interpretation of a set of facial expressions by Western and Japanese participants. Performance in the forced choice task exceeded that measured in the free naming task for both cultures, but the Japanese participants were found to be particularly poor at labelling expressions of fear and disgust. The difficulties experienced with translation and interpretation in these tasks led to the development of a psychophysical paradigm which was used to measure the signalling strength of facial expressions without the need for participants to interpret what they saw. Psychophysical tasks were also used to measure sensitivity to eye gaze direction. A 'live' and screen-based task produced comparable thresholds and revealed that our sensitivity to these ocular signals was at least as good as Snellen acuity. Manipulations of the facial surround in the screen-based task revealed that the detection of gaze direction was facilitated by the presence of the facial surround and as such it can be assumed that gaze discriminations are likely to be made in conjunction with other face processing analyses. The tasks developed in these chapters were used to test two patients with bilateral amygdala damage. Patients with this brain injury have been reported to experience difficulties in the interpretation of facial and auditory signals of fear. In this thesis, their performance was found to depend on the task used to measure it. However, neither patient was found to be impaired in their ability to label fearful expressions compared to control participants. Instead, patient SE demonstrated a consistently poor performance in his ability to interpret expressions of disgust. Vll Experiments 2, 3, 4 and 5 of Chapter 3, have also been reported in Perception, 1995, Vol. 24, Supplement, pp. 14. The Face as a long distance transmitter. Jenkins, J., Craven, B. & Bruce, V. Experiments 1,2,3 and 4 of Chapter 3 were also reported in the Technical Report of the Institute of Electronics Information and Communication Engineers. HIP 96-39 (1997-03). Methods for detecting social signals from the face. Jenkins, J., Craven, B., Bruce, V., & Akamatsu, S. Experiments 2 and 5 of Chapter 3, and a selection of the patient studies from Chapter 6 were reported at the Experimental Psychology Society, Bristol meeting, 1996, and at the Applied Vision Association, Annual Meeting, April, 1996. Sensitivity to Expressive Signals from the Human Face: Psychophysical and Neuropsychological Investigations. Jenkins, J., Bruce, V., Calder, A., & Craven, B.

Thesis (Ph.D.) -- McMaster University, 1998. / Includes bibliographical references (leaves [236]-245). Also available via World Wide Web.

Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [276]-291).

Thesis (M. A. in Psychology)--Vanderbilt University, Aug. 2009. / Title from title screen. Includes bibliographical references.

Thesis (Ph. D.)--University of Missouri-Columbia, 2008. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 3, 2009) Vita. Includes bibliographical references.

Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 69-75).

archives@tulane.edu / Making eye contact is one of the earliest, most important forms of communication. Newborns are sensitive to adults’ gaze direction (Farroni, Massaccesi, Pividori, & Johnson, 2004), and by 4 months infants learn more about an object that an adult has looked at (Reid & Striano, 2005). Emotional facial expressions influence infants’ scanning of adults’ eyes (Shepard & Spence, 2012), which may affect their sensitivity to eye gaze cues. In two experiments, we examined the effects of silent dynamic emotional messages on 6-month-old infants’ scanning of face features, as well as their sensitivity to and learning from eye gaze cues. In Experiment 1, infants completed a gaze cueing task in which speakers delivered silent approving, comforting, prohibition, and neutral messages and then shifted their eye gaze to a peripheral target. Although infants showed increased attention to the eyes during prohibition and comforting messages, all infants showed enhanced gaze cueing in the context of approving messages. Moreover, female infants showed trend-level gaze cueing following approving messages, whereas male infants showed trend-level gaze cueing following neutral messages. In Experiment 2, a separate group of infants completed a similar gaze cueing task that included a visual paired comparison test phase to examine learning of the gaze-cued and non-cued targets, based on the hypothesis that increased sensitivity to gaze cues would enhance learning of the cued targets. As in Experiment 1, infants showed increased attention to the eyes during comforting messages. However, we did not find any reliable gaze cueing effects. Infants spent more time looking at test targets following approving messages but did not show evidence of enhanced learning of cued targets. Overall, findings from both experiments suggest that 6-month-olds are more responsive to gaze cues in the context of approving messages, underscoring the significance of positive infant-directed interactions to the development of early joint attention. We conclude by discussing clinical implications, limitations (including a relevant error in Experiment 2), and future directions. / 1 / Claire Frances Noonan

No description available.

Les recherches menées au cours de cette thèse de Doctorat s'inscrivent dans les activités du laboratoire commun OPERA (OPtique EmbaRquée Active) impliquant ESSILOR-LUXOTTICA et le CNRS. L’objectif est de contribuer au développement des “lunettes du futur” intégrant des fonctions d'obscurcissement, de focalisation ou d'affichage qui s’adaptent en permanence à la scène et au regard de l’utilisateur. Ces nouveaux dispositifs devront être dotés de capacités de perception, de décision et d’action, et devront respecter des contraintes d'encombrement, de poids, de consommation énergétique et de temps de traitement. Ils présentent par conséquent des connexions évidentes avec la robotique. Dans ce contexte, les recherches ont consisté à investiguer la structure et la construction de tels systèmes afin d’identifier leurs enjeux et difficultés. Pour ce faire, la première tâche a été de mettre en place des émulateurs de divers types de lunettes actives, qui permettent de prototyper et d’évaluer efficacement diverses fonctions. Dans cette phase de prototypage et de test, ces émulateurs s’appuient naturellement sur une architecture logicielle modulaire typique de la robotique. La seconde partie de la thèse s'est focalisée sur le prototypage d’un composant clé des lunettes du futur, qui implique une contrainte supplémentaire de basse consommation : le système de suivi du regard, aussi appelé oculomètre. Le principe d’un assemblage de photodiodes et d’un traitement par réseau de neurones a été proposé. Un simulateur a été mis au point, ainsi qu’une étude de l'influence de l'agencement des photodiodes et de l’hyper-paramétrisation du réseau sur les performances de l'oculomètre. / The research carried out during this doctoral thesis takes place within the OPERA joint laboratory (OPtique EmbaRquée Active) involving ESSILOR-LUXOTTICA and the CNRS. The aim is to contribute to the development of "glasses of the future", which feature obscuration, focus or display capabilities that continuously adapt to the scene and the user gaze. These new devices will be endowed with perception, decision and action capabilities, and will have to respect constraints of space, weight, energy consumption and processing time. They therefore show obvious connections with robotics. In this context, the structure and building of such systems has been investigated in order to identify their issues and difficulties. To that end, the first task was to set up emulators of various types of active glasses, which enable the prototyping and effective testing of various functions. In this prototyping and testing phase, these emulators naturally rely on a modular software architecture typical of robotics. The second part of the thesis focused on the prototyping of a key component which implies an additional constraint on low consumption, namely the eye tracking system, also known as gaze tracker. The principle of a photodiode assembly and of a neural network processing has been proposed. A simulator has been developed, as well as a study of the influence of the arrangement of photodiodes and the hyper-parametrization of the network on the performance of the oculometer.

Master of Science / Psychological Sciences / Lester C. Loschky / A fundamental issue in visual attention is the relationship between the useful field of view (UFOV), the region of visual space where information is encoded within a single fixation, and eccentricity. A common assumption is that impairing attentional resources reduces the size of the UFOV (i.e. “tunnel vision”). However, most research has not accounted for eccentricity-dependent changes in spatial resolution, potentially conflating fixed visual properties with flexible changes in visual attention. Williams (1988; 1989) argued that foveal loads are necessary to reduce the size of the UFOV, producing "tunnel vision". Without a foveal load, it is argued that the attentional decrement is constant across the visual field (i.e. "general interference"). However, other research asserts that auditory working memory (WM) loads produce tunnel vision. To date, foveal versus auditory WM loads have not been compared to determine if they differentially change the size of the UFOV. In two experiments, we tested the effects of a foveal (rotated L vs. T discrimination) task, and an auditory WM (N-back) task on an extrafoveal (Gabor) discrimination task. Gabor patches were scaled for size and processing time to produce equal performance across the visual field under single task conditions, thus removing the confound of eccentricity-dependent differences in visual sensitivity. The results showed that while both foveal and auditory loads reduced Gabor orientation sensitivity, only the foveal load interacted with retinal eccentricity to produce tunnel vision, clearly demonstrating task-specific changes to the form of the UFOV. This has theoretical implications for understanding the UFOV.