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yes / How well can neurotypical adults’ interpret mental states in people with ASD? ‘Targets’ (ASD and neurotypical) reactions to four events were video-recorded then shown to neurotypical participants whose task was to identify which event the target had experienced. In study 1 participants were more successful for neurotypical than ASD targets. In study 2, participants rated ASD targets equally expressive as neurotypical targets for three of the events, while in study 3 participants gave different verbal descriptions of the reactions of ASD and neurotypical targets. It thus seems people with ASD react differently but not less expressively to events. Because neurotypicals are ineffective in interpreting the behaviour of those with ASD, this could contribute to the social difficulties in ASD.

No / Parameterisation of facial expressions on PDE surface representations of human faces are presented in this work. Taking advantage of the boundary-value approach inherent to Bloor-Wilson PDE method, facial expressions are achieved by manipulating the original boundary curves. Such curves are responsible for generating a surface representation of a human face in its neutral configuration, so that regions on these curves represent a given facial expression in a fast and realistic manner. Additionally, the parameterisation proposed here is carried out by applying different mathematical transformations to the affected curves according to the corresponding facial expression. Full analytic expressions parameterising some of the most common facial expressions such as smiling and eyebrow raising are in this work. Some graphical examples of these facial expressions are used to illustrate the results obtained using Bloor-Wilson PDE method as the foundations of the parameterisation scheme proposed here. Thus, it is shown that an efficient, intuitive and realistic parameterisation of facial expressions is attainable using Bloor-Wilson PDE method in along with a suitable mathematical expression.

This study investigates the relationship between the uncanny valley effect and perceived facial expressions in anthropomorphized virtual animals. This thesis builds upon previous research by the author in the hopes of addressing previously identified limitations and reinforcing the data of the earlier study. The aim is to examine whether the uncanny valley effect can be triggered by a mismatch between realistic and stylized facial animations applied to a realistic or stylized 3D animal, and if this effect varies depending on the expression portrayed. A research questionnaire was used to assess whether participants experience uncanniness when there is a discrepancy between the level of realism and stylization in the animation of virtual animals. The findings of the study indicated that the hypothesis is true even with the additional improvements and greater scrutiny concluding that the study will contribute to the understanding of the uncanny valley effect in relation to anthropomorphized virtual animals.

The purpose of this research was to enhance the methods towards the development of an efficient three dimensional face recognition system. More specifically, one of our aims was to investigate how the use of curvature of the diagonal profiles, extracted from 3D facial geometry models can help the neutral face recognition processes. Another aim was to use a gender classifier employed on 3D facial geometry in order to reduce the search space of the database on which facial recognition is performed. 3D facial geometry with facial expression possesses considerable challenges when it comes face recognition as identified by the communities involved in face recognition research. Thus, one aim of this study was to investigate the effects of the curvature-based method in face recognition under expression variations. Another aim was to develop techniques that can discriminate both expression-sensitive and expression-insensitive regions for ii face recognition based on non-neutral face geometry models. In the case of neutral face recognition, we developed a gender classification method using support vector machines based on the measurements of area and volume of selected regions of the face. This method reduced the search range of a database initially for a given image and hence reduces the computational time. Subsequently, in the characterisation of the face images, a minimum feature set of diagonal profiles, which we call T shape profiles, containing diacritic information were determined and extracted to characterise face models. We then used a method based on computing curvatures of selected facial regions to describe this feature set. In addition to the neutral face recognition, to solve the problem arising from data with facial expressions, initially, the curvature-based T shape profiles were employed and investigated for this purpose. For this purpose, the feature sets of the expression-invariant and expression-variant regions were determined respectively and described by geodesic distances and Euclidean distances. By using regression models the correlations between expressions and neutral feature sets were identified. This enabled us to discriminate expression-variant features and there was a gain in face recognition rate. The results of the study have indicated that our proposed curvature-based recognition, 3D gender classification of facial geometry and analysis of facial expressions, was capable of undertaking face recognition using a minimum set of features improving efficiency and computation.

Psychiatric patients, particularly schizophrenics, tend to be less accurate decoders of facial expressions than normals. The involvement of three basic information processing stages in this deficit was investigated: attention; encoding; and processing. Psychiatric inpatients, classified by diagnosis and severity of pathology, and nonpatient controls were administered seven facial cue decoding tasks. Orientation of attention was assessed through rate of diversion of gaze from the stimuli. Encoding was assessed using simple tasks, requiring one contrast of two facial stimuli and selection from two response alternatives. Processing was assessed using a more complex task, requiring several contrasts between stimulus faces and selection from numerous response alternatives. Residualized error scores were used to statistically control for effects of attention on task performance. Processing task performance was evaluated using ANCOVA to control for effects of encoding. Schizophrenics were characterized by generalized information processing deficit while affective disorder subjects evidenced impairment only in attending. Attention impairments in both groups were related to severity of psychopathology. Problems in encoding and processing were related only to a schizophrenic diagnosis. Their decoding deficits appeared attributable to general visuospatial discrimination impairment rather than repression-sensitization defenses or the affective connotation of cues. Adequacy of interpersonal functioning was associated with measures of attending and processing but not encoding. The measures of encoding, however, may have lacked adequate discriminating power due to low difficulty.

L'environnement semble jouer un rôle important dans le développement de la discrimination des stimuli sociaux. Le développement précoce de la discrimination des stimuli sociaux tels que les visages et les expressions faciales a suscité de nombreuses recherches. Par ailleurs, les individus avec autisme ne semblent pas répondre aux stimuli sociaux de la même façon que des individus au fonctionnement normal et ces différences apparaissent de manière précoce.Cependant, les recherches actuelles ne nous fournissent pas assez d'éléments dur la façon dont cette discrimination se met en place, en particulier sur les régions du visage qui sont importantes pour la discrimination. C'est ce point que nous avons choisi d'étudier au cours de cette thèse, auprès d'enfants avec autisme. Les travaux effectués dans le cadre de cette thèse ont eu pour objectifs tout d'abord de développer une tâche permettant de mesurer les éléments du visage impliqués dans la discrimination d'expressions faciales chez des enfants au développement typique et des enfants avec autisme (Etudes 1 & 2). Puis, nous avons mis en place une tâche ayant pour objectif d'évaluer l'importance des régions des yeux et de la bouche auprès d'enfants avec autisme et de montrer l'effet de la modification des patterns d'observation des visages sur la façon dont les éléments du visage exercent un contrôle discriminatif sur les réponses des enfants avec autisme (Etudes 3 & 4). Ces résultats sont discutés au regard de l'importance de l'environnement dans la mise en place de la discrimination des stimuli sociaux. Les implications concernant les recherches chez l'enfant au développement typique seront discutées, ainsi que la place de la direction du regard, en plus de l'expression des yeux, comme élément discriminatif / The role of the environment has been demonstrated in the development of the discrimination of social stimuli. The discrimination of social stimuli such as faces and facial expressions have been extensively studied during the past decades. In addition, people with autism show atypical responses to social stimuli compared to typically functioning individuals. Those discrepancies can be seen very early in life. However, there is still much to know about how this learning takes place, particularly on the face parts that are relevant for the discrimination. The focus of this work is to study more precisely how face parts come to control the responses of children with autism. The goal of our studies was first, to build a task to measure precisely which parts of the face are involved in facial expressions discrimination in children with autism and in typically developing children (Experiments 1 & 2). Subsequently, we devised a task which evaluated the role of the eyes' and mouth regions in children with autism and typically developing children in order to see the effect of the modification of observing patterns of faces on the way eyes and mouth come to control the responses of children with autism (Experiments 3 & 4). Results are discussed in line with the role of the environment in participating in the development of facial expressions discrimination. Implications for the study in early facial expression discrimination learning in typically developing children are discussed. Direction of gaze, in adition to the eyes region expression, is discussed as a relevant element for the discrimination of facial stimuli.

Pesquisas demonstram que estímulos olfatórios podem afetar a identificação expressões faciais, embora os resultados sejam inconsistentes. De acordo com estes estudos, odores podem aumentar a velocidade do processo, porém somente as expressões de nojo e felicidade foram estudadas. Este estudo teve como objetivo investigar a influência de odorantes no reconhecimento de cinco expressões faciais (medo, raiva, felicidade, nojo e tristeza). Em dois experimentos, foi realizada uma tarefa de tempo de reação (RT) enquanto os sujeitos foram expostos a estimulação olfatória. Os participantes avaliaram as propriedades de valência e ativação (arousal) dos odores após a realização da tarefa. No primeiro experimento a performance dos participantes não foi diferente entre as estimulações olfativas, e uma segunda análise foi realizada organizando-se os dados de acordo com a valência hedônica subjetiva dos odores. Os resultados demonstram que as expressões de tristeza foram reconhecidas significativamente mais devagar que felicidade e raiva na estimulação afetiva agradável, mas não para as condições neutra (sem odor) e desagradável. No experimento 2 foram encontradas diferenças significativas entre o limiar para percepção de tristeza e felicidade para o odorante agradável, mas não nas outras condições. Concluímos que a influência dos odorantes na percepção de expressões faciais provavelmente não se limita a efeitos de congruência e incongruência emocional, e possivelmente pode ser passível de influência ativação dos odores. Nossos resultados do experimento 1 foram mais coerentes quando consideramos a valência como uma dimensão de aproximação/afastamento. Estes resultados salientam a importância da seleção do grupo de estímulos e da análise da reação emocional dos participantes aos odores, em experimentos que utilizem estimulação olfativa / Research demonstrated that olfactory stimuli can influence the identification of facial expressions, although the results are inconsistent. According to these experiments, odors can enhance the speed of the process, but only disgust and happiness were tested. The objective of this study was to investigate the influence of odorants in recognition of five facial expressions (fear, anger, happiness, disgust ad sadness). In two experiments, a reaction time task (RT) was performed meanwhile subjects were exposed to olfactory stimulation. Participants rated the properties of valence and arousal of the odors after completing the task. In the first experiment the participants performance was not different between the odorants, and a second analysis was conducted with the data organized according to the subjective hedonic valence attributed to the odors. subjective hedonic valence attributed to the odors. Results show that the facial expressions of sadness were identified significantly slower than happiness and anger in the pleasant affective stimulation, but not for the neutral and unpleasant conditions. In experiment 2 significant differences were found between the perception thresholds of happiness and sadness for the pleasant odorant, but not in the other conditions. We conclude that the influences of the olfactory stimuli in the perception of facial expressions are probably not limited to emotional congruence and incongruence effects, and are possibly influenced by the arousal of the odors. Our results of experiment 1 were more coherent when we considered valence as a dimension of approach/withdrawal. This data reinforces the importance of odor stimuli selection and analysis of the emotional reactions elicited by the odorants in each participant

Made available in DSpace on 2016-07-27T14:20:33Z (GMT). No. of bitstreams: 1 Raquel Santana Schiavon Sanchez.pdf: 411121 bytes, checksum: c2c5e5e09cb21ce2c58fcaccfc1de299 (MD5) Previous issue date: 2007-03-12 / This study investigates the influence of non-verbal communication on the efficiency of salespersons, through an analysis of how well different subjects can perceive-recognize universal facial expressions of emotions. Our subjects were 15 salespeople employed by a retail and service company and 100 graduate business students of a university in Goiânia. A questionnaire and the “reading faces” test (Ekman (2003) were applied to each subject. The test consists of 14 photographs of the face of a same person with facial expressions of sadness, disgust, happiness, anger, fear and disdain. The hypthesis, that the more one knows how to interpret emotional facial expressions, the more successful persons are in their sales results (as presented in the literature), was not confirmed, although it was demonstrated in the study that all the salespeople tend to make use of non-verbal communication in their daily activities. / Este estudo é uma investigação acerca da influência da comunicação não-verbal na eficiêcia dos vendedores, através de uma análise da facilidade com que diferentes sujeitos percebem-reconhecem expressões faciais de emoções universais. Participaram deste experimento 15 vendedores de empresa varejista e de serviço e 100 alunos do curso de graduação em administração de uma universidade em Goiânia, GO. Foi aplicado um questionário e o teste “Lendo faces” do Ekman(2003), que consiste em 14 fotos do rosto de um mesmo sujeito com as expressões de emoções faciais de tristeza, nojo, alegria, raiva, medo e desdenho. Não foi confirmada a hipótese de que quanto mais sabe-se interpretar as expressões faciais de emoção, mais sucesso as pessoas têm em seus resultados de vendas, como é apresentado na literatura, embora todos os vendedores tendem a fazer uso da interpretação da comunicação não-verbal nas suas atividades diárias, como ficou demonstrado na pesquisa

O presente trabalho teve como objetivo verificar a aquisição de função simbólica de expressões emocionais por nomes de alimentos verdadeiros e fictícios em adolescentes, por meio do paradigma de equivalência de estímulos. No Estudo I foram ensinadas relações entre as faces humanas expressando alegria e neutralidade com nomes de alimentos verdadeiros pelo procedimento de matching-to-sample simultâneo, diferindo a quantidade de treino em três grupos experimentais (segundo e terceiro grupo com supertreino). Os retratos faciais (conjunto A) foram relacionados a conjuntos de estímulos abstratos (conjuntos B e C); estímulos do conjunto B foram relacionados a nomes de alimentos (D). Portanto, as relações AB, AC e BD foram treinadas. Ao final foi conduzido o teste de equivalência CD/DC. Para avaliação inicial e final dos alimentos, foi utilizado um questionário com cinqüenta nomes de alimentos anexados a uma escala de avaliação de cinco pontos composta de expressões faciais e um teste de preferência alimentar com dez alimentos selecionados do questionário. Cinqüenta e cinco participantes da quinta série do ensino fundamental de escolas públicas e particulares concluíram o Estudo I. Trinta e cinco participantes mostraram desempenhos consistentes na fase de estabelecimento de equivalência de estímulos (nove do Grupo 1, onze do Grupo 2 e quinze do Grupo 3). Entre esses participantes, o alimento treinado com a face alegre foi avaliado em ambos os instrumentos como mais agradável por sessenta e seis porcento dos participantes do primeiro grupo e quarenta e cinco porcento do terceiro grupo. No segundo grupo, quarenta e cinco porcento avaliaram mais positivamente este alimento no pós teste de preferência alimentar. Em relação à face neutra feminina, os participantes dos Grupos 2 e 3 apresentaram avaliações finais mais positivas nos instrumentos finais . Porém, em relação ao alimento equivalente à face neutra masculina, destaca-se uma redução na avaliação do pós-teste de preferência nos Grupos Experimentais 2 e 3. O Estudo II teve como objetivo verificar se a transferência de função ocorreria se fossem utilizados nomes fictícios de alimentos relacionados com expressões esquemáticas de alegria, neutralidade e tristeza pelo procedimento de matching-to-sample com atraso. Os estímulos que diferiram do Estudo I foram os dos conjuntos A e D, compostos por faces esquemáticas e nomes fictícios de alimentos (capira, fulito e piteba), respectivamente. Um questionário com uma escala de cinco pontos de expressões esquemáticas foi usada como pré e pós teste. Trinta e seis participantes concluíram o Estudo II, dos quais vinte e cinco apresentaram desempenhos consistentes no teste de equivalência. A interação entre os questionários versus alimento teve um efeito significativo (p<0,001) no grupo de participantes que atingiram o critério de equivalência. Os participantes aumentaram as avaliações finais de capira (treinado com a face alegre), mantiveram avaliações finais muito próximas às iniciais no alimento fulito (treinado com a face neutra) e, diminuíram consideravelmente o pós teste do alimento piteba (treinado com a face triste). / The aim of the present study was to verify the acquisition of symbolic properties of facial expressions of emotion for real and fictitious food names in adolescents, using a stimulus equivalence paradigm. In Experiment 1, conditional relations between facial expressions (one of happiness and two expressing emotion neutrality) and real food names were trained by simultaneous matching-to-sample procedure. Three experimental groups differed only on the amount of training (Group 2 and 3 with overtraining). Pictures of facial expressions (Set-A) were related to abstract line drawing stimulus (Set-B and Set-C); C stimuli were related to food names (D). So, the AB, AC and BD relations were trained. Finally, they received the equivalence tests CD/DC. The participants were asked to rate the foods names for pleasantness in the beginning and in the end of the experiment by a questionnaire with fifty food names. These were linked to a five point scale of facial expressions and a preference test that had ten food names selected from the questionnaire. Fifty five participants that were in the fifth grade of public and private schools concluded Experiment I. Thirty five participants demonstrated equivalence (nine in Group 1, eleven in Group 2 and 15 in Group 3). The food trained with the happy face was valued in both final instruments of evaluation of the food preference as more pleasant by sixty six percent of the Group 1 participants and forty five percent of the Group 3. In Group 2, forty five percent valued as more pleasant this food only in the final evaluation of the preference test. The food related to the feminine neutral face showed more positive evaluations in Groups 2 and 3. On the other hand, the food equivalent to the masculine neutral face had a reduction in the food preference test in Groups 2 and 3. Experiment II aimed to verify if the transfer of function would happen if fictitious names of foods related to facial expressions of happiness, neutrality and sadness were used via delayed matching-to-sample procedure. Stimuli of Set-A and Set-D were different from Experiment I and had schematic expressions and fictitious food names (capira, fulito and piteba), respectively. A five point scale questionnaire of schematic expressions was used to value the fictitious names of foods in the beginning and in the end of the experiment. Thirty six participants finished Experiment II and twenty five showed stimulus equivalence. There was a significant interaction between the final evaluations and fictitious food names (p<0,001) in the equivalence group. The participants increased the final evaluations of the food trained with the happy face (capira), maintained almost the same evaluations of the food related with the neutral face (fulito) and considerably reduced the judgments of piteba, which was trained with the sad face.