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Eickholt, Molly S. "FACE THREAT, FACE SUPPORT, AND ADVICE EFFECTIVENESS FOLLOWING INFIDELITY." UKnowledge, 2013. http://uknowledge.uky.edu/comm_etds/15.
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This study examined advice interactions following infidelity. Participants (N = 213) completed a survey concerning an instance on infidelity and a subsequent advice interaction. Injured party perceptions of advice interactions were measured by examining advice messages, perceived face threat, and perceived face support, in addition to perceived effectiveness of the advice message. Results from this study showed no significant differences in perceived face threat, perceived face support, or advice effectiveness between different advice messages. Results also indicated both positive and negative face threat as negative predictors of advice effectiveness. While negative face support was a positive predictor of advice effectiveness, positive face support was a negative predictor. When controlling for relational closeness, negative face support was the only significant predictor of advice effectiveness.
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Smith, Anjelica Marie. "The Deliberative Potential of Social Media: Face Threat and Face Support in Online Political Expression." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/73670.
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Engaging in productive political discussion has long been a valued aspect of American democratic life. Due to ease of access and the potential for exposure to diverse views, the Internet and social media may support mediated political talk. Literature on the concept of face and politeness theory provides a framework for understanding interpersonal interactions, both online and offline. To understand if social media has the potential to host political discussion among millennials, a survey (N = 352) of undergraduate students examined social media use and political interaction experiences. Facebook was the most popular platform for exposure to others' political opinions and political self-expression. Facebook users with more diverse networks engaged in more political expression. Across numerous platforms, participants reported frequently being exposed to others' political opinions but infrequently sharing their own views. Negative and positive political interactions on Facebook and Twitter were explored for their threat to and support of negative face (need for autonomy) and positive face (need for validation). Findings indicate that engaging in negative interactions leads to more face threat while observing negative interactions solicits more face support. Engaging in positive interactions results in more face support and observing positive interactions leads to more face threat. Across interaction type and platform, participants who actively engaged in political interactions as opposed to merely observing them reported significantly more subsequent online political engagement. Future research on political interactions across various social media platforms and the application of interpersonal communication theory to the study of mediated political talk is warranted.Master of Arts
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Reid, Chelsea. "ATTITUDE ALIGNMENT AMONG COUPLES IN THE FACE OF BELONGING THREAT." VCU Scholars Compass, 2011. http://scholarscompass.vcu.edu/etd/208.
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The present research sought to expand upon previous research demonstrating that individuals shift their attitudes to match the attitudes of their romantic partner. This research examined whether attitude alignment is influenced, in part, by belonging threats. Participants reported their attitudes about social issues and were randomly assigned to receive a belonging threat (or acceptance) in the form of feedback about their future relationships prior to discussing issues about which they disagreed with their partner. Partners discussed issues that were central to self - peripheral to partner and peripheral to self - central to partner. Attitude alignment was measured following discussion and at a one-week follow-up. Attitude alignment was expected to vary as a function of belonging threat, centrality of issue, and strength of unit relationship. Results did not support hypotheses, but did reveal noteworthy points to be considered for future work in this area.
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Wang, Hong, and 王紅. "Help seeking tendency in situation of threat to self-esteem and face-losing." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B3124371X.
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Wang, Hong. "Help seeking tendency in situation of threat to self-esteem and face-losing /." Hong Kong : University of Hong Kong, 2002. http://sunzi.lib.hku.hk/hkuto/record.jsp?B2470927x.
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Spikes, Antonio L. "CLASSROOM RACIAL POLITICS, FACEWORK, AND FACE THREAT: THE IDENTITY MANAGEMENT PRACTICES OF BLACK MALE TEACHERS." OpenSIUC, 2019. https://opensiuc.lib.siu.edu/dissertations/1708.
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The purpose of this dissertation is to improve the racial conditions of USAmerican education and to highlight how racial politics influence the facework practices of Black male teachers, their perceptions of and responses to face threats, and how the classroom, as a context, shapes perceptions and issues of face, facework, and face threat. I utilized identity management theory to examine how Black male teachers construct facework and face threat within the classroom. Additionally, I used semi-structured respondent interviewing and grounded theory as my method and analytical method (respectively) to complete my study. Using key concepts, such as positive face, negative face, face threat, and identity freezing, I concluded that perceptions of racism and racial stereotypes that are sometimes contingent on their gender identity impact how they constructed positive and negative face. Additionally, racism and racial stereotypes shaped which facework strategies the interview participants utilized, what they considered face threatening situations, how they responded to face threatening situations, and what they considered identity freezing situations. Overall, their constructions of facework and face threat were utilized to avoid stereotypes that depicted them as angry and incompetent. Considering the positive potential of this study, I concluded with how this research can help administrators and colleagues to improve the education system for Black male teachers.
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Hadden, Alexis A. "Face Threat Mitigation in Feedback: An Examination of Student Apprehension, Self-Efficacy, and Perceived Emotional Support." UKnowledge, 2017. http://uknowledge.uky.edu/comm_etds/59.
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This experimental study examined the effects of an instructor’s face threat mitigation tactics on student self-efficacy for learning and perceived emotional support from the instructor in a written feedback setting. Participants (N = 401) were randomly assigned to one of four feedback scenarios in which level of face threat mitigation and instructor age and status were manipulated. Student grade orientation and state feedback apprehension were measured prior to being exposed to the feedback scenario. Results indicate that high face threat mitigation is positively associated with student self-efficacy for learning and perceived emotional support from the instructor. Results also revealed that state feedback apprehension predicts self-efficacy for learning and perceived emotional support from the instructor. Grade orientation predicted self-efficacy for learning but did not significantly predict perceived emotional support from the instructor providing feedback. Finally, scenarios manipulated for instructor age and status did not significantly differ in self-efficacy for learning or perceived emotional support from the instructor. Implications regarding theory, the measurement of feedback apprehension, and student-instructor communication are discussed.
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Juth, Pernilla. "Finding the emotional face in the crowd and the role for threat-biased attention in social anxiety." Stockholm : Department of Clinical Neuroscience, Karolinska Institutet, 2010. http://diss.kib.ki.se/2010/978-91-7409-746-7/.
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Lindersson, Carl. "Threatening Measures, at Face Value : Electrophysiology Indicating Confounds of the Facial Width-to-Height Ratio." Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-17350.
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Previous studies support that the relative width of the upper face (facial width-to-height ratio; fWHR) has evolved to signal threat, but these studies rely greatly on subjective facial ratings and measurements prone to confounds. The present study objectively quantifies threat perception to the magnitude of the observers’ electrophysiological reaction, specifically the event-related potential (ERP) called the late positive potential (LPP), and investigate if brow height and jaw width could have confounded previous fWHR studies. Swedish and international students (N = 30, females = 11, Mage = 24 years, SDage = 2.9) were shown computer-generated neutral faces created with the underlying skeletal morphology varying in brow ridge height, cheekbone width and jaw width. Participants first rated how threatening each face was and then viewed 12 blocks of 64 faces while their electroencephalography (EEG) was recorded. The results supported that the LPP could be used to index threat perception and showed that only brow height significantly affected both facial ratings (p < .001, ɳp2 = .698) and magnitude of the LPP within the 400 to 800 ms latency (p = .02, d = .542). Hence, brow height, not facial width, could explain previous findings. The results contradict the hypothesis that fWHR is an evolved cue of threat and instead support the overgeneralisation hypothesis in that faces with similar features to anger will be perceived as more threatening.
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Trad, Laura. "The Effect of Face Threat Mitigation on Instructor Credibility and Student Motivation in the Absence of Instructor Nonverbal Immediacy." Master's thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5877.
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Many years of communication research have shown that an increase in immediacy has been a major factor that affects students' perceptions of instructor credibility which in turn affects, both students' cognitive and affective learning, student state motivation and a variety of other positive outcomes. However, in order for immediacy to be effective, instructor and student must be in the same location at the same time. With the recent push toward on-line classes, what can we find to act like immediacy in a text based format? This research suggests that face threat mitigation can be used in a text-based environment, to achieve the pro-social goals of instructor credibility and student state motivation to the same extent as it does when coupled with immediacy. This study is a replication of a study done by Witt and Kerssen-Griep (2012). In the original study face threat mitigation (FTM) was coupled with instructor nonverbal immediacy (NVI) and they examined the impact these factors had on instructor credibility (i.e., competence, character, and caring) and student state motivation in a video simulated feedback situation. This study surveyed 218 undergraduate students in an introductory communication course. Students were randomly assigned to read hypothetical scenarios in which FTM was manipulated in a manner similar to Witt and Kerssen-Griep's study. They responded to three scales. The current study removed the instructor by using a simulated electronic feedback correspondence. Results of a MANCOVA and four separate ANOVAs were similar to those of the original findings. FTM was found to have a significant positive relationship with instructor credibility (i.e., competence, character, and caring) and student state motivation.M.A.
Masters
Communication
Sciences
Communication; Interpersonal Communication
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Lassetter, Bethany. "Stigma management through a threat-specific lens: when do targets anticipate and seek to manage the prejudice they face?" Thesis, University of Iowa, 2018. https://ir.uiowa.edu/etd/6174.
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When do targets of stigma seek to manage the prejudice they face? Recent work shows that stigmatized targets anticipate that others view their group as posing specific threats, and as a result, prioritize threat-mitigating strategies when motivated to convey a positive impression (e.g., Black men prioritize smiling to reduce physical safety threat; Neel, Neufeld, & Neuberg, 2013). I predicted that stigmatized targets use these strategies selectively: First, with people vulnerable to the threat the target is stereotyped to pose, and second, in environments that make the target’s threat salient. Black and White male participants read about a hypothetical interaction with a stranger and then ranked self-presentational strategies in order of importance for making a good impression. Study 1 showed that environmental threat and partner vulnerability did not influence rank of smiling; however, after being made aware of stereotypes people hold of African Americans in general (Study 2), Black men trended toward prioritizing smiling more in a threatening (compared to a non-threatening) environment or with a vulnerable (compared to a non-vulnerable) partner. Although further work is needed to replicate this effect before drawing concrete conclusions, this finding speaks to targets strategically employing threat-reducing behaviors with specific perceivers and in certain environments.
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Zhang, Shuangyue. "Is honesty the best policy? Honest but hurtful evaluative messages in romantic relationships." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1123853679.
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Thesis (Ph. D.)--Ohio State University, 2005.Title from first page of PDF file. Document formatted into pages; contains iii, v, 138 p.; also includes graphics. Includes bibliographical references (p. 128-138). Available online via OhioLINK's ETD Center
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Lee, Dirkson Christopher. "I don't know why it's funny, but I'll laugh anyway: Analysis of feigned laughter in the context of face-threatening-utterances." CSUSB ScholarWorks, 2001. https://scholarworks.lib.csusb.edu/etd-project/1965.
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The purpose of this thesis is to reveal some of the behavioral characteristics of a specific type of laughter that I term "feigned laughter," and how it is used in the context of face-threatening-utterances (FTUs), or utterances that threaten the face needs of an individual.
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Pooter, Hélène de. "Le droit international face aux pandémies : vers un système de sécurité sanitaire collective ?" Thesis, Paris 1, 2013. http://www.theses.fr/2013PA010343.
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Face aux pandémies, le droit international s'organise-t-il sous la forme d'un « système de sécurité sanitaire collective» (abandon des mesures unilatérales excessives - garantie offerte par la collectivité par le biais d'une action commune - sauvegarde du droit des États d'adopter les mesures individuelles nécessaires) ? L'étude des instruments adoptés au sein de l'OMS (Règlement sanitaire international et Cadre de préparation en cas de grippe pandémique), des actes unilatéraux de l'ONU (résolutions de l'Assemblée générale, du Conseil de sécurité et du Conseil économique et social), de la coopération entre organisations intergouvernementales et des accords de l'OMC (GATT, Accord SPS et Accord sur les ADPIC) révèle que chaque segment de la question reçoit une réponse positive. Pourtant, on ne peut ignorer le caractère largement imparfait du résultat de la lutte contre les pandémies. S'il existe indéniablement des indices en faveur de la thèse selon laquelle un système de sécurité sanitaire collective serait en formation, le droit international face aux pandémies se caractérise par un agglomérat de fragments aux antipodes d'un édifice juridique cohérentIn the face of pandemics, is international law organized as a "system of collective health security" (foregoing excessive unilateral measures - guaranteed by the community through joint action - upholding State rights to adopt necessary individual measures)? The study of instruments adopted by the WHO (International Health Regulations, Pandemic Influenza Preparedness Framework), of unilateral acts of the UN (resolutions of the General Assembly, the Security Council and the Economic and Social Council), of cooperation between international organizations and of the WTO's Agreements (GATT, SPS Agreement and TRIPS Agreement) reveals that the answer to each segment of the question is positive. However, one cannot ignore the highly imperfect result of the fight against pandemics. If there are undeniable indices which illustrate the existence of a nascent system of collective health security, international law in the face of pandemics is nevertheless thus far characterized by an agglomerate of fragments at odds with a coherent legal edifice
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Green, Melissa Jayne. "Facial affect processing in delusion-prone and deluded individuals: A continuum approach to the study of delusion formation." University of Sydney. Psychology, 2002. http://hdl.handle.net/2123/792.
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This thesis examines attentional and cognitive biases for particular facial expressions in delusion-prone and deluded individuals. The exploration of cognitive biases in delusion-prone individuals provides one means of elucidating psychological processes that might be involved in the genesis of delusions. Chapter 1 provides a brief review of the continuum approach to schizophrenia, and outlines recent theoretical conceptualisations of delusions. The study of schizophrenia phenomena at the symptom level has become a popular method of inquiry, given the heterogeneous phenotypic expression of schizophrenia, and the uncertainty surrounding the existence of a core neuropathology. Delusions are one of the most commonly experienced symptoms of schizophrenia, and have traditionally been regarded as fixed, false beliefs that are pathognomonic of an organic disease process. However, recent phenomenological evidence of delusional ideation in the general population has led to the conceptualisation of delusions as multi-dimensional entities, lying at the extreme end of a continuum from normal through to maladaptive beliefs. Recent investigations of the information processing abnormalities in deluded individuals are reviewed in Chapter 2. This strand of research has revealed evidence of various biases in social cognition, particularly in relation to threat-related material, in deluded individuals. These biases are evident in probabilistic reasoning, attribution style, and attention, but there has been relatively little investigation of cognitive aberrations in delusion-prone individuals. In the present thesis, social-cognitive biases were examined in relation to a standard series of faces that included threat-related (anger, fear) and non-threatening (happy, sad) expressions, in both delusion-prone and clinically deluded individuals. Chapters 3 and 4 present the results of behavioural (RT, affect recognition accuracy) and visual scanpath investigations in healthy participants assessed for level of delusion- proneness. The results indicate that delusion-prone individuals are slower at processing angry faces, and show a general (rather than emotion-specific) impairment in facial affect recognition, compared to non-prone healthy controls. Visual scanpath studies show that healthy individuals tend to direct more foveal fixations to the feature areas (eyes, nose, mouth) of threat-related facial expressions (anger, fear). By contrast, delusion-prone individuals exhibit reduced foveal attention to threat-related faces, combined with �extended� scanpaths, that may be interpreted as an attentional pattern of �vigilance-avoidance� for social threat. Chapters 5 and 6 extend the work presented in Chapters 3 and 4, by investigating the presence of similar behavioural and attentional biases in deluded schizophrenia, compared to healthy control and non-deluded schizophrenia groups. Deluded schizophrenia subjects exhibited a similar delay in processing angry faces, compared to non-prone control participants, while both deluded and non-deluded schizophrenia groups displayed a generalised affect recognition deficit. Visual scanpath investigations revealed a similar style of avoiding a broader range of negative (anger, fear, sad) faces in deluded schizophrenia, as well as a common pattern of fewer fixations with shorter duration, and reduced attention to facial features of all faces in both deluded and non-deluded schizophrenia. The examination of inferential biases for emotions displayed in facial expressions is presented in Chapter 7 in a study of causal attributional style. The results of this study provide some support for a �self-serving� bias in deluded schizophrenia, as well as evidence for an inability to appreciate situational cues when making causal judgements in both delusion-prone and deluded schizophrenia. A theoretical integration of the current findings is presented in Chapter 8, with regard to the implications for cognitive theories of delusions, and neurobiological models of schizophrenia phenomena, more generally. Visual attention biases for threat-related facial expressions in delusion-prone and deluded schizophrenia are consistent with proposals of neural dysconnectivity between frontal-limbic networks, while attributional biases and impaired facial expression perception may reflect dysfunction in a broader �social brain� network encompassing these and medial temporal lobe regions. Strong evidence for attentional biases and affect recognition deficits in delusion-prone individuals implicates their role in the development of delusional beliefs, but the weaker evidence for attributional biases in delusion-prone individuals suggests that inferential biases about others� emotions may be relevant only to the maintenance of delusional beliefs (or that attributional biases for others� emotional states may reflect other, trait-linked difficulties related to mentalising ability). In summary, the work presented in this thesis demonstrates the utility of adopting a single-symptom approach to schizophrenia within the continuum framework, and attests to the importance of further investigations of aberrant social cognition in relation to the development of delusions.
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Connors, Marianne Dorothy. "The pragmatic particles 'enfin' and 'écoute' in French film and TV dialogue." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/27764.
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This thesis investigates the use of the pragmatic particles (PPs) 'enfin' and 'écoute' in French film dialogue, and their translations in British English subtitles. Using a corpus of nine films and eight episodes drawn from two television series – all released in the UK between 2005 and 2015, and equating to approximately twenty-two hours – the study identifies tokens across a much wider range of contexts than has previously been possible using traditional corpora. The main contribution is an analysis of PP functions. The results for 'enfin' show a different functional distribution of the particle to other corpora, with corrective 'enfin' occurring significantly less frequently. The relatively large number of tokens of performative and emotional (or affective) 'enfin' allows for an elaboration of these two categories, and a tendency is observed for 'enfin' to appear as an apparent disagreement mitigator in discussions between peers. With regard to 'écoute', it is argued that écoute1 functions as a face-threat mitigator in unequal relationships and écoute2 as an FTA, although the particle is multifunctional and some tokens exhibit characteristics of both categories. Attention is given to combinations of 'enfin' and 'écoute' with other particles: while there is a clear tendency for disagreement-mitigating 'enfin' to co-occur with 'mais', and for the precision and restrictive subcategories of the corrective to co-occur with 'je veux dire', other previously documented combinations ('enfin bon' and 'ben écoute') are not frequently occurring in the present corpus. The thesis also makes a significant contribution to the field of Audiovisual Translation (AVT). The English subtitles show high rates of omission for both particles consistent with previous research, with disagreement-mitigating 'enfin' particularly vulnerable to omission. However, the analysis reveals a surprising pattern regarding 'écoute': a clear division of labour between ‘look’ (used to translate more confrontational tokens) and ‘listen’ (more conciliatory and socially distant). The study includes an experimental analysis of the subtitles relative to their character limits, demonstrating a potential new approach for researchers wishing to investigate the impact of various subtitling constraints.
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Lee, Jinho. "Synthesis and analysis of human faces using multi-view, multi-illumination image ensembles." Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1133366279.
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Castle, Gina. "LET'S GIVE THEM SOMETHING TO TALK ABOUT: EXPLORING RACISM AND RACIAL TENSIONS AS POTENTIAL FACE THREATS IN BLACK AND WHITE INTERRACIAL RELATIONSHIPS." Master's thesis, University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3360.
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This study examined how racism and racial tensions potentially threatened the face needs of Black and White interracial couples. Specifically, this study investigated the benefit of family approval of one's interracial relationship. Couples use of corrective face work in response to prejudice was also examined. This research used a qualitative, interpretive method to gather and analyze data from 14 personal interviews. The interview schedule enabled interviewees to use storytelling to share their experience of being in a Black and White interracial relationship. Interviewees were asked questions surrounding their experience as the partner in an interracial relationship. Couples shared how they told their family that their romantic partner was a different race and shared how they encountered prejudice when they are out in public. Further, they spoke about how people stare at them and make comments about their interracial relationship. The data underwent a thematic analysis (Owen, 1984) where I reviewed the data and searched for themes that were recurrent and repeated by interviewees. There were several themes that emerged. First, the very presence of racial tensions and racism affects interracial couples. Second, family support seemed to mitigate threats to couples' positive and negative faces and enabled couples to engage in open and honest dialogue with their family and their significant other. Finally, even couples with family support, engaged in corrective face work to respond to the face threats posed by racism and racial tensions.M.A.
Nicholson School of Communication
Sciences
Communication MA
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Chan, Yin-man. "Three-dimensional cephalometry of Chinese faces." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43958643.
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Chan, Yin-man, and 陳彥民. "Three-dimensional cephalometry of Chinese faces." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43958643.
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Hunter, David W. "Synthesis of facial ageing transforms using three-dimensional morphable models." Thesis, St Andrews, 2009. http://hdl.handle.net/10023/763.
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Tiddeman, Bernard. "Three-dimensional morphanalysis of the face." Thesis, Heriot-Watt University, 1998. http://hdl.handle.net/10399/633.
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Chen, Xiaochen. "Tracking vertex flow on 3D dynamic facial models." Diss., Online access via UMI:, 2008.
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Stahl, Jonathan L. "Reading Faces: Inferring Physical Traits from Behavioral Descriptions." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1496307932460106.
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Wei, Xiaozhou. "3D facial expression modeling and analysis with topographic information." Diss., Online access via UMI:, 2008.
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Tibbalds, Adam Dominic. "Three dimensional human face acquisition for recognition." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624854.
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Darby, Rachel K. "Compromising Face-to-Face Confrontation: Does the Protected Child Witness Threaten Impartial Juror Decision-Making?" Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/scripps_theses/224.
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The use of protective testimonial aids by the child witness has been advocated for as research indicates that it decreases witness stress and suggestibility; however, the use of such aids has also been attacked as incompatible with the defendant’s confrontational right and the fact-finding function of the jury. The present study examines the effects of testimony modality, as well as empathy-inducing closing arguments, on juror perceptions of the child witness, perceptions of the defendant, and ultimate judgments of guilt. In this between-subjects factorial study, workers on Amazon Mechanical Turk were invited to participate in an online simulated sexual assault case survey. Participants read all trial stimuli, which consisted of written juror instructions, case facts, testimonies, closing arguments, and legal definitions. In addition, participants were exposed to photographs depicting the child witness testifying under one of three possible conditions (direct, shielded, CCTV) and either read the prosecutor’s closing argument that contained a specific empathy-inducing portion or did not. Results indicated that regardless of testimony modality and empathy-inducing closing arguments, jurors did not exhibit a pro-prosecution or pro-defense bias.
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Huang, Di. "Robust face recognition based on three dimensional data." Phd thesis, Ecole Centrale de Lyon, 2011. http://tel.archives-ouvertes.fr/tel-00693158.
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The face is one of the best biometrics for person identification and verification related applications, because it is natural, non-intrusive, and socially weIl accepted. Unfortunately, an human faces are similar to each other and hence offer low distinctiveness as compared with other biometrics, e.g., fingerprints and irises. Furthermore, when employing facial texture images, intra-class variations due to factors as diverse as illumination and pose changes are usually greater than inter-class ones, making 2D face recognition far from reliable in the real condition. Recently, 3D face data have been extensively investigated by the research community to deal with the unsolved issues in 2D face recognition, Le., illumination and pose changes. This Ph.D thesis is dedicated to robust face recognition based on three dimensional data, including only 3D shape based face recognition, textured 3D face recognition as well as asymmetric 3D-2D face recognition. In only 3D shape-based face recognition, since 3D face data, such as facial pointclouds and facial scans, are theoretically insensitive to lighting variations and generally allow easy pose correction using an ICP-based registration step, the key problem mainly lies in how to represent 3D facial surfaces accurately and achieve matching that is robust to facial expression changes. In this thesis, we design an effective and efficient approach in only 3D shape based face recognition. For facial description, we propose a novel geometric representation based on extended Local Binary Pattern (eLBP) depth maps, and it can comprehensively describe local geometry changes of 3D facial surfaces; while a 81FT -based local matching process further improved by facial component and configuration constraints is proposed to associate keypoints between corresponding facial representations of different facial scans belonging to the same subject. Evaluated on the FRGC v2.0 and Gavab databases, the proposed approach proves its effectiveness. Furthermore, due tq the use of local matching, it does not require registration for nearly frontal facial scans and only needs a coarse alignment for the ones with severe pose variations, in contrast to most of the related tasks that are based on a time-consuming fine registration step. Considering that most of the current 3D imaging systems deliver 3D face models along with their aligned texture counterpart, a major trend in the literature is to adopt both the 3D shape and 2D texture based modalities, arguing that the joint use of both clues can generally provides more accurate and robust performance than utilizing only either of the single modality. Two important factors in this issue are facial representation on both types of data as well as result fusion. In this thesis, we propose a biological vision-based facial representation, named Oriented Gradient Maps (OGMs), which can be applied to both facial range and texture images. The OGMs simulate the response of complex neurons to gradient information within a given neighborhood and have properties of being highly distinctive and robust to affine illumination and geometric transformations. The previously proposed matching process is then adopted to calculate similarity measurements between probe and gallery faces. Because the biological vision-based facial representation produces an OGM for each quantized orientation of facial range and texture images, we finally use a score level fusion strategy that optimizes weights by a genetic algorithm in a learning pro cess. The experimental results achieved on the FRGC v2.0 and 3DTEC datasets display the effectiveness of the proposed biological vision-based facial description and the optimized weighted sum fusion. [...]
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Li, Huibin. "Towards three-dimensional face recognition in the real." Phd thesis, Ecole Centrale de Lyon, 2013. http://tel.archives-ouvertes.fr/tel-00998798.
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Due to the natural, non-intrusive, easily collectible, widespread applicability, machine-based face recognition has received significant attention from the biometrics community over the past three decades. Compared with traditional appearance-based (2D) face recognition, shape-based (3D) face recognition is more stable to illumination variations, small head pose changes, and varying facial cosmetics. However, 3D face scans captured in unconstrained conditions may lead to various difficulties, such as non-rigid deformations caused by varying expressions, data missing due to self occlusions and external occlusions, as well as low-quality data as a result of some imperfections in the scanning technology. In order to deal with those difficulties and to be useful in real-world applications, in this thesis, we propose two 3D face recognition approaches: one is focusing on handling various expression changes, while the other one can recognize people in the presence of large facial expressions, occlusions and large pose various. In addition, we provide a provable and practical surface meshing algorithm for data-quality improvement. To deal with expression issue, we assume that different local facial region (e.g. nose, eyes) has different intra-expression/inter-expression shape variability, and thus has different importance. Based on this assumption, we design a learning strategy to find out the quantification importance of local facial regions in terms of their discriminating power. For facial description, we propose a novel shape descriptor by encoding the micro-structure of multi-channel facial normal information in multiple scales, namely, Multi-Scale and Multi-Component Local Normal Patterns (MSMC-LNP). It can comprehensively describe the local shape changes of 3D facial surfaces by a set of LNP histograms including both global and local cues. For face matching, Weighted Sparse Representation-based Classifier (W-SRC) is formulated based on the learned quantification importance and the LNP histograms. The proposed approach is evaluated on four databases: the FRGC v2.0, Bosphorus, BU-3DFE and 3D-TEC, including face scans in the presence of diverse expressions and action units, or several prototypical expressions with different intensities, or facial expression variations combine with strong facial similarities (i.e. identical twins). Extensive experimental results show that the proposed 3D face recognition approach with the use of discriminative facial descriptors can be able to deal with expression variations and perform quite accurately over all databases, and thereby has a good generalization ability. To deal with expression and data missing issues in an uniform framework, we propose a mesh-based registration free 3D face recognition approach based on a novel local facial shape descriptor and a multi-task sparse representation-based face matching process. [...]
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Heseltine, Thomas David. "Face recognition : two-dimensional and three-dimensional techniques." Thesis, University of York, 2005. http://etheses.whiterose.ac.uk/9880/.
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Duncan, Andrew Wilson. "Exploring attentional bias towards threatening faces in chimpanzees." Kyoto University, 2019. http://hdl.handle.net/2433/244515.
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付記する学位プログラム名: 霊長類学・ワイルドライフサイエンス・リーディング大学院Kyoto University (京都大学)
0048
新制・課程博士
博士(理学)
甲第22034号
理博第4538号
新制||理||1652(附属図書館)
京都大学大学院理学研究科生物科学専攻
(主査)教授 友永 雅己, 准教授 宮地 重弘, 教授 濱田 穣
学位規則第4条第1項該当
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Abbott, Amanda Helen. "The acquisition and analysis of craniofacial data in three dimensions /." Title page, contents and summary only, 1988. http://web4.library.adelaide.edu.au/theses/09PH/09pha131.pdf.
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Thesis (Ph. D.)--Dept. of Dentistry, University of Adelaide, 1990.Typescript (Photocopy). A stereo-viewer is provided ... to facilitate fusing of the three dimensional CT reconstructions and the stereo wire frame models--Pref. v. 2. Includes bibliographical references (leaves [244]-263).
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Jayaratne, Yasas Shri Nalaka. "Three-dimensional assessment of facial deformities and their surgical outcomes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hdl.handle.net/10722/210236.
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Data on the three?dimensional (3?D) morphology of normal faces and
facial deformities as well as objective techniques for evaluating postoperative
changes are currently unavailable. With the advent of stereophotography and
cone?beam CT (CBCT), it is possible to acquire 3?D images of soft and hard
tissues of the maxillofacial complex. A series of studies were conducted aimed
at 1) establishing 3?D facial anthropometric norms for Hong Kong young
adults, 2) determining 3?D facial anthropometric features in skeletal Class II
and III deformities, 3) characterizing the oropharyngeal space in Class II and III
skeletal deformities, 4) exploring clinical applications of 3?D colour maps, 5)
establishing a non?invasive technique for estimating serial volume changes
and 6) creating virtual craniofacial models by fusing 3?D photographs and
CBCT images.
Study 1: A stereophotographic system was used to capture 3?D images of 103
Hong Kong Chinese young adults with normal balanced faces. An
anthropometric analysis protocol with linear, angular and proportional
measurements was developed to establish a normative database and quantify
dysmorphology. The Hong Kong Chinese norms were distinct from Caucasians,
especially with regard to ocular and nasal measurements. Facial height and
nasolabial measurements differed significantly between Hong Kong males and
females.
Study 2: Anthropometric analyses of 3?D facial images from 41 skeletal Class II
and 43 Class III subjects were performed. The Class II subjects had increased
lower facial height compared with Class III, who had longer total facial heights
and narrower faces. While Class II deformity primarily resulted from
mandibular deficiency with a normal maxilla, Class III presented as combined
midfacial hypoplasia and mandibular hyperplasia.
Study 3: Anthropometric characteristics of the oropharygeal space in skeletal
Class II and III were evaluated using 62 CBCT scans. The retroglossal (RG) and
retropalatal (RP) volumes and average cross sectional areas were significantly
larger in Class III than Class II skeletal deformity. The RP compartment was
larger but less uniform than the RG compartment in both Classes.
Study 4: 3?D photographs or CBCT images acquired at two different time
points were superimposed using a common unaffected area. 3?D colour maps
were generated depicting distance differences between superimposed images
in a graphical format. These maps were used as an objective tool for
treatment planning and assessing outcomes after orthognathic surgery,
bimaxillary distraction and facial trauma.
Study 5: 3?D photogrammetry was employed for planning soft tissue
expansion (STE) and transplantation of a vascularised scapular flap in
hemifacial microsomia. This technique facilitated the identification of extent
and degree of tissue deficiency, selection of the appropriate tissue expander,
monitoring volumetric changes during STE and estimation of the free flap
dimensions.
Study 6: 3?D facial photographs and CBCT scans of 29 subjects were merged
to create virtual craniofacial models with natural surface texture. Accuracy
was assessed with 3?D colour maps and Root Mean Square (RMS) error. The
CBCT and 3?D photographic data were integrated while minimizing average
RMS error to 0.441mm. These virtual composite craniofacial models
permitted concurrent 3?D assessment of bone and soft tissue.published_or_final_version
Dentistry
Doctoral
Doctor of Philosophy
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Zangeneh, Reza. "Thread-parallel mesh generation and improvement using face-edge swapping and vertex insertion." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/51007.
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The purpose of this thesis is three-fold. First, we devise a memory model for unstructured mesh data for efficient use of memory on parallel shared memory architectures with the purpose of lowering the synchronization overhead between threads and also excluding the probability of occurring race conditions. Second, we present a new thread-parallel edge and face swapping algorithm for two and three dimensional meshes using OpenMP for shared memory architectures. We show how removing the conflicts from the reconfiguration procedure by applying a vertex locking strategy can result in a near linear speed-up with parallel efficiency of close to one on two threads and 70% with sixteen threads on shared-memory processors. Finally, we derive a parallel mesh generation and refinement module for shared memory architectures based on pre-existing serial modules — GRUMMP — by implementing Chernikov and Chrisochoides’ parallel insertion algorithm along with the two above tools. Experiments show a worst case parallel efficiency of 60% for parallel refinement with 16 threads.Applied Science, Faculty of
Mechanical Engineering, Department of
Graduate
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Gaskovski, Peter. "Exploring the influence of threat, ambiguity, and identity in angry faces." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ53493.pdf.
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Pokalova, Elena. "Shifting Faces of Terror after 9/11: Framing the Terrorist Threat." Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1322435499.
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Cadavid, Steven. "Human Identification Based on Three-Dimensional Ear and Face Models." Scholarly Repository, 2011. http://scholarlyrepository.miami.edu/oa_dissertations/516.
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We propose three biometric systems for performing 1) Multi-modal Three-Dimensional (3D) ear + Two-Dimensional (2D) face recognition, 2) 3D face recognition, and 3) hybrid 3D ear recognition combining local and holistic features. For the 3D ear component of the multi-modal system, uncalibrated video sequences are utilized to recover the 3D ear structure of each subject within a database. For a given subject, a series of frames is extracted from a video sequence and the Region-of-Interest (ROI) in each frame is independently reconstructed in 3D using Shape from Shading (SFS). A fidelity measure is then employed to determine the model that most accurately represents the 3D structure of the subject’s ear. Shape matching between a probe and gallery ear model is performed using the Iterative Closest Point (ICP) algorithm. For the 2D face component, a set of facial landmarks is extracted from frontal facial images using the Active Shape Model (ASM) technique. Then, the responses of the facial images to a series of Gabor filters at the locations of the facial landmarks are calculated. The Gabor features are stored in the database as the face model for recognition. Match-score level fusion is employed to combine the match scores obtained from both the ear and face modalities. The aim of the proposed system is to demonstrate the superior performance that can be achieved by combining the 3D ear and 2D face modalities over either modality employed independently. For the 3D face recognition system, we employ an Adaboost algorithm to builda classifier based on geodesic distance features. Firstly, a generic face model is finely conformed to each face model contained within a 3D face dataset. Secondly, the geodesic distance between anatomical point pairs are computed across each conformed generic model using the Fast Marching Method. The Adaboost algorithm then generates a strong classifier based on a collection of geodesic distances that are most discriminative for face recognition. The identification and verification performances of three Adaboost algorithms, namely, the original Adaboost algorithm proposed by Freund and Schapire, and two variants – the Gentle and Modest Adaboost algorithms – are compared. For the hybrid 3D ear recognition system, we propose a method to combine local and holistic ear surface features in a computationally efficient manner. The system is comprised of four primary components, namely, 1) ear image segmentation, 2) local feature extraction and matching, 3) holistic feature extraction and matching, and 4) a fusion framework combining local and holistic features at the match score level. For the segmentation component, we employ our method proposed in [111], to localize a rectangular region containing the ear. For the local feature extraction and representation component, we extend the Histogram of Categorized Shapes (HCS) feature descriptor, proposed in [111], to an object-centered 3D shape descriptor, termed Surface Patch Histogram of Indexed Shapes (SPHIS), for surface patch representation and matching. For the holistic matching component, we introduce a voxelization scheme for holistic ear representation from which an efficient, element-wise comparison of gallery-probe model pairs can be made. The match scores obtained from both the local and holistic matching components are fused to generate the final match scores. Experimental results conducted on the University of Notre Dame (UND) collection J2 dataset demonstrate that theproposed approach outperforms state-of-the-art 3D ear biometric systems in both accuracy and efficiency.
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Rajwade, Ajit. "Facial pose estimation and face recognition from three-dimensional data." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82410.
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Face recognition from 3D shape information has been proposed as a method of biometric identification in recent times. This thesis presents a 3D face recognition system capable of recognizing the identity of an individual from his/her 3D facial scan in any pose across the view-sphere, by suitably comparing it with a set of models stored in a database. The system makes use of only 3D shape information ignoring textural information completely.Firstly, the thesis proposes a generic learning strategy using support vector regression [11] to estimate the approximate pose of a 3D scan. The support vector machine (SVM) is trained on range images in several poses, belonging to a small set of individuals. This thesis also examines the relationship between size of the range image and the accuracy of the pose prediction from the scan.
Secondly, a hierarchical two-step strategy is proposed to normalize a facial scan to a nearly frontal pose before performing recognition. The first step consists of a coarse normalization making use of either the spatial relationships between salient facial features or the generic learning algorithm using the SVM. This is followed by an iterative technique to refine the alignment to the frontal pose, which is basically an improved form of the Iterated Closest Point Algorithm [17]. The latter step produces a residual error value, which can be used as a metric to gauge the similarity between two faces. Our two-step approach is experimentally shown to outdo both the individual normalization methods in terms of recognition rates, over a very wide range of facial poses. Our strategy has been tested on a large database of 3D facial scans in which the training and test images of each individual were acquired at significantly different times, unlike several existing 3D face recognition methods.
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Aljarrah, Inad A. "Three Dimensional Face Recognition Using Two Dimensional Principal Component Analysis." Ohio University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1142453613.
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Yeganeh, Behzad, Mohammad Hashemi, Serres Fredrick J. de, Marek Jan Los, and Saeid Ghavami. "Different Faces of Hepatocellular Carcinoma as a Health Threat in 21st Century." Linköpings universitet, Cellbiologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-89877.
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Scoales, M. "Facial affect recognition and attentional bias to threat faces in positive schizotypy." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/968209/.
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Part 1-The Literature Review explores the topic of attentional bias which is thought to be a component of many anxiety disorders. A review of the literature on dot-probe studies of anxious individuals which used faces as stimuli found 24 studies. Studies of both socially anxious and generally anxious individuals suggest attentional bias in the initial, orienting stage of attention, which is increased by conditions of social threat. The review concludes that attentional vigilance for threat is a consistent feature of anxiety disorders including both social anxiety and GAD. There is little or no evidence to support the view that anxiety disorders are characterised by attentional avoidance of threat faces, as measured by the dot-probe paradigm. Part 2 -The Empirical Paper reports on a study of facial affect recognition and attentional bias in psychosis-prone participants. Data collection was shared with another trainee (see Appendix D). There was no difference in facial affect recognition between the two groups. The high schizotypy group did however display a significantly greater attentional bias score at 2000ms, and a significantly lower attentional bias score at lOOms, than the non psychosis-prone group. The limitations, clinical and research implications of this study are discussed. Part 3 -The Critical Appraisal describes the selection of the topic, ethical and theoretical considerations, an appraisal of the design and methodology, as well as reflections on the research process as a whole.
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Choi, KyoungHo. "A framework for automatic creation of talking heads for multimedia applications /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/5955.
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Zou, Le. "3D face recognition with wireless transportation." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1448.
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Prewitt, Thomas Joseph. "Quasi-static, Deformable-body Analysis of a Face Gear-Thrust Bearing System." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1344867144.
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O'Mara, David Thomas John. "Automated facial metrology." University of Western Australia. School of Computer Science and Software Engineering, 2002. http://theses.library.uwa.edu.au/adt-WU2003.0015.
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Automated facial metrology is the science of objective and automatic measurement of the human face. There are many reasons for measuring the human face. Psychologists are interested in determining how humans perceive beauty, and how this is related to facial symmetry [158]. Biologists are interested in the relationship between symmetry and biological fitness [124]. Anthropologists, surgeons, forensic experts, and security professionals can also benefit from automated facial metrology [32, 101, 114]. This thesis investigates the concept of automated facial metrology, presenting original techniques for segmenting 3D range and colour images of the human head, measuring the bilateral symmetry of n-dimensional point data (with particular emphasis on measuring the human head), and extracting the 2D profile of the face from 3D data representing the head. Two facial profile analysis techniques are also presented that are incremental improvements over existing techniques. Extensive literature reviews of skin colour modelling, symmetry detection, symmetry measurement, and facial profile analysis are also included in this thesis. It was discovered during this research that bilateral symmetry detection using principal axes is not appropriate for detecting the mid-line of the human face. An original mid-line detection technique that does not use symmetry, and is superior to the symmetry-based technique, was developed as a direct result of this discovery. There is disagreement among researchers about the effect of ethnicity on skin colour. Some researchers claim that people from different ethnic groups have the same skin chromaticity (hue, saturation) [87, 129, 206], while other researchers claim that different ethnic groups have different skin colours [208, 209]. It is shown in this thesis that people from apparently different ethnic groups can have skin chromaticity that is within the same Gaussian distribution. The chromaticity-based skin colour model used in this thesis has been chosen from the many models previously used by other researchers, and its applicability to skin colour modelling has been justified. It is proven in this thesis that the Mahalanobis distance to the skin colour distribution is Gaussian in both the chromatic and normalised rg colour spaces. Most facial profile analysis techniques use either tangency or curvature to locate anthropometric features along the profile. Techniques based on both approaches have been implemented and compared. Neither approach is clearly superior to the other, but the results indicate that a hybrid technique, combining both approaches, could provide significant improvements. The areas of research most relevant to facial metrology are reviewed in this thesis and original contributions are made to the body of knowledge in each area. The techniques, results, literature reviews, and suggestions presented in this thesis provide a solid foundation for further research and hopefully bring the goal of automated facial metrology a little closer to being achieved.
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McCool, Christopher Steven. "Hybrid 2D and 3D face verification." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16436/.
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Face verification is a challenging pattern recognition problem. The face is a biometric that, we as humans, know can be recognised. However, the face is highly deformable and its appearance alters significantly when the pose, illumination or expression changes. These changes in appearance are most notable for texture images, or two-dimensional (2D) data. But the underlying structure of the face, or three dimensional (3D) data, is not changed by pose or illumination variations. Over the past five years methods have been investigated to combine 2D and 3D face data to improve the accuracy and robustness of face verification. Much of this research has examined the fusion of a 2D verification system and a 3D verification system, known as multi-modal classifier score fusion. These verification systems usually compare two feature vectors (two image representations), a and b, using distance or angular-based similarity measures. However, this does not provide the most complete description of the features being compared as the distances describe at best the covariance of the data, or the second order statistics (for instance Mahalanobis based measures). A more complete description would be obtained by describing the distribution of the feature vectors. However, feature distribution modelling is rarely applied to face verification because a large number of observations is required to train the models. This amount of data is usually unavailable and so this research examines two methods for overcoming this data limitation: 1. the use of holistic difference vectors of the face, and 2. by dividing the 3D face into Free-Parts. The permutations of the holistic difference vectors is formed so that more observations are obtained from a set of holistic features. On the other hand, by dividing the face into parts and considering each part separately many observations are obtained from each face image; this approach is referred to as the Free-Parts approach. The extra observations from both these techniques are used to perform holistic feature distribution modelling and Free-Parts feature distribution modelling respectively. It is shown that the feature distribution modelling of these features leads to an improved 3D face verification system and an effective 2D face verification system. Using these two feature distribution techniques classifier score fusion is then examined. This thesis also examines methods for performing classifier fusion score fusion. Classifier score fusion attempts to combine complementary information from multiple classifiers. This complementary information can be obtained in two ways: by using different algorithms (multi-algorithm fusion) to represent the same face data for instance the 2D face data or by capturing the face data with different sensors (multimodal fusion) for instance capturing 2D and 3D face data. Multi-algorithm fusion is approached as combining verification systems that use holistic features and local features (Free-Parts) and multi-modal fusion examines the combination of 2D and 3D face data using all of the investigated techniques. The results of the fusion experiments show that multi-modal fusion leads to a consistent improvement in performance. This is attributed to the fact that the data being fused is collected by two different sensors, a camera and a laser scanner. In deriving the multi-algorithm and multi-modal algorithms a consistent framework for fusion was developed. The consistent fusion framework, developed from the multi-algorithm and multimodal experiments, is used to combine multiple algorithms across multiple modalities. This fusion method, referred to as hybrid fusion, is shown to provide improved performance over either fusion system on its own. The experiments show that the final hybrid face verification system reduces the False Rejection Rate from 8:59% for the best 2D verification system and 4:48% for the best 3D verification system to 0:59% for the hybrid verification system; at a False Acceptance Rate of 0:1%.
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Cook, James Allen. "A decompositional investigation of 3D face recognition." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16653/.
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Automated Face Recognition is the process of determining a subject's identity from digital imagery of their face without user intervention. The term in fact encompasses two distinct tasks; Face Verficiation is the process of verifying a subject's claimed identity while Face Identification involves selecting the most likely identity from a database of subjects. This dissertation focuses on the task of Face Verification, which has a myriad of applications in security ranging from border control to personal banking. Recently the use of 3D facial imagery has found favour in the research community due to its inherent robustness to the pose and illumination variations which plague the 2D modality. The field of 3D face recognition is, however, yet to fully mature and there remain many unanswered research questions particular to the modality. The relative expense and specialty of 3D acquisition devices also means that the availability of databases of 3D face imagery lags significantly behind that of standard 2D face images. Human recognition of faces is rooted in an inherently 2D visual system and much is known regarding the use of 2D image information in the recognition of individuals. The corresponding knowledge of how discriminative information is distributed in the 3D modality is much less well defined. This dissertations addresses these issues through the use of decompositional techniques. Decomposition alleviates the problems associated with dimensionality explosion and the Small Sample Size (SSS) problem and spatial decomposition is a technique which has been widely used in face recognition. The application of decomposition in the frequency domain, however, has not received the same attention in the literature. The use of decomposition techniques allows a map ping of the regions (both spatial and frequency) which contain the discriminative information that enables recognition. In this dissertation these techniques are covered in significant detail, both in terms of practical issues in the respective domains and in terms of the underlying distributions which they expose. Significant discussion is given to the manner in which the inherent information of the human face is manifested in the 2D and 3D domains and how these two modalities inter-relate. This investigation is extended to cover also the manner in which the decomposition techniques presented can be recombined into a single decision. Two new methods for learning the weighting functions for both the sum and product rules are presented and extensive testing against established methods is presented. Knowledge acquired from these examinations is then used to create a combined technique termed Log-Gabor Templates. The proposed technique utilises both the spatial and frequency domains to extract superior performance to either in isolation. Experimentation demonstrates that the spatial and frequency domain decompositions are complimentary and can combined to give improved performance and robustness.
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Filmer, Hannah. "Processing of emotional expression in subliminal and low-visibility images." Thesis, University of Exeter, 2012. http://hdl.handle.net/10036/4045.
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This thesis investigated the processing of emotional stimuli by the visual system, and how the processing of emotions interacts with visual awareness. Emotions have been given ‘special’ status by some previous research, with evidence that the processing of emotions may be relatively independent of striate cortex, and less affected by disruption to awareness than processing of emotionally neutral images. Yet the extent to which emotions are ‘special’ remains questionable. This thesis focused on the processing of emotional stimuli when activity in V1 was disrupted using transcranial magnetic stimulation (TMS), and whether emotional properties of stimuli can be reliably discriminated, or affect subsequent responses, when visibility is low. Two of the experiments reported in this thesis disrupted activity in V1 using TMS, Experiment 1 with single pulses in an online design, and Experiment 2 with theta burst stimulation in an offline design. Experiment 1 found that a single pulse of TMS 70-130 ms following a presentation of a body posture image disrupted processing of neutral but not emotional postures in an area of the visual field that corresponded to the disruption. Experiment 2 did not find any convincing evidence of disruption to processing of neutral or emotional faces. From Experiment 1 it would appear that emotional body posture images were relatively unaffected by TMS, and appeared to be robust to disruption to V1. Experiment 2 did not add to this as there was no evidence of disruption in any condition. Experiments 3 and 4 used visual masking to disrupt awareness of emotional and neutral faces. Both experiments used a varying interval between the face and the mask stimuli to systematically vary the visibility of the faces. Overall, the shortest SOA produced the lowest level of visibility, and this level of visibility was arguably outside awareness. In Experiment 3, participants’ ability to discriminate properties of emotional faces under low visibility conditions was greater than their ability to discriminate the orientation of the face. This was despite the orientation discrimination being much easier at higher levels of visibility. Experiment 4 used a gender discrimination task, with emotion providing a redundant cue to the decision (present half of the time). Despite showing a strong linear masking function for the neutral faces, there was no evidence of any emotion advantage. Overall, Experiment 3 gave some evidence of an emotion advantage under low visibility conditions, but this effect was fairly small and not replicated in Experiment 4. Finally, Experiments 5-8 used low visibility emotional faces to prime responses to subsequent emotional faces (Experiments 5 and 6) or words (Experiments 7 and 8). In Experiments 5, 7 and 8 there was some evidence of emotional priming effects, although these effects varied considerably across the different designs used. There was evidence for meaningful processing of the emotional prime faces, but this processing only led to small and variable effects on subsequent responses. In summary, this thesis found some evidence that the processing of emotional stimuli was relatively robust to disruption in V1 with TMS. Attempts to find evidence for robust processing of emotional stimuli when disrupted with backwards masking was less successful, with at best mixed results from discrimination tasks and priming experiments. Whether emotional stimuli are processed by a separate route(s) in the brain is still very much open to debate, but the findings of this thesis offers small and inconsistent evidence for a brain network for processing emotions that is relatively independent of V1 and visual awareness. The network and nature of brain structures involved in the processing of subliminal and low visibility processing of emotions remains somewhat elusive.
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Alali, Ala. "The influence of breathing disorders on face shape : a three-dimensional study." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/60386/.
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Breathing disorders can potentially influence craniofacial development through interactions between the respiratory flow and genetic and environmental factors. It has been suggested that certain medical conditions such as persistent rhinitis and renal insufficiency may have an influence on face shape. The effects of these conditions are likely to be subtle; otherwise they would appear as an obvious visible facial feature. The use of three-dimensional imaging provides the opportunity to acquire accurate and high resolution facial data to explore the influence of medical condition on facial morphology. Therefore, the aim of the present study is to investigate the influence of breathing disorders (asthma, atopy, allergic rhinitis and sleep disordered breathing) on face shape in children. The study sample, comprising of 4784 British Caucasian children of which 2922 (61.1%) were diagnosed with a breathing disorder, was selected from the Avon Longitudinal Study of Parents and Children (ALSPAC), which had been conducted to investigate the genetic and environmental determinants of development, health and disease. Three-dimensional surface laser scans were conducted on the children when they were 15 years old. A total of 21 reproducible facial landmarks (x, y, z co-ordinates) were identified. Average facial shells were constructed for each of the different disease groups and compared to facial shells of healthy asymptomatic children. Face-shape variables (angular and linear measurements) were analysed with respect to the different breathing disorders by employing a variety of statistical methods, including t-tests, chi-square tests, principal component analysis, binary logistic regression and analysis of variance (ANOVA). The results reveal that individual breathing disorders have varying influences on facial features, including increased anterior lower face height, a more retrognathic mandible and reduced nose width and prominence. The study also shows that the early removal of adenoids and tonsils can have a significant effect on obstructive breathing, resulting in the restoration of the facial morphology to its normal shape. This was particularly evident in children with normal BMIs. Surprisingly, no significant differences in face shape were detected in children with multiple diseases (combinations of asthma, allergic rhinitis, atopy and sleep-disordered breathing) when compared to healthy children. This may indicate the multifactorial, complex character of this spectrum of diseases. The findings provide evidence of small but potentially real associations between breathing disorders and face shape. This was largely attributable to the use of high-resolution and reproducible three-dimensional facial imaging alongside a large study sample. They also provide the scientific community with a detailed and effective methodology for static facial modelling that could have clinical relevance for early diagnosis of breathing disorders. Furthermore, this research has demonstrated that the ALSPAC patient archive offers a valuable resource to clinicians and the scientific community for investigating associations between various breathing disorders and face shape.
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Leclerc, Camille. "Biodiversité endémique insulaire face aux changements globaux : état des lieux dans un contexte de conservation." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS507.
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Les changements globaux, du fait de l’empreinte humaine, sont associés à de nombreux déclins de populations et de disparitions d'espèces, et ce, notamment au sein des systèmes insulaires. L'importante biodiversité abritée par de tels écosystèmes est particulièrement vulnérable aux pressions anthropiques en raison de diverses caractéristiques (p. ex. syndrome d’insularité, faible redondance fonctionnelle, isolement géographique des îles). En dépit de cette vulnérabilité accrue, peu d’études se sont jusqu'à lors intéressées à ces systèmes comme modèle d’étude pour évaluer les patrons de menaces sur les différentes facettes de la diversité (taxonomique, fonctionnelle, et phylogénétique). Pourtant, un tel travail permettrait d’améliorer notre compréhension des menaces qui pèsent au sein des îles. Dans ce sens, l’objectif de cette thèse est de décrire les patrons de diversité endémique insulaire dans le contexte actuel des changements globaux et dans un contexte futur de changements climatiques, en explorant les différentes facettes de la diversité. Une finalité de ce travail est de mettre en évidence des priorités éventuelles de conservation pour ces écosystèmes particulièrement vulnérables. Nous avons abordé l'ensemble de ce travail de thèse à une grande échelle à l’aide de deux bases données recensant les îles mondiales et les espèces qui y sont endémiques. Dans une première partie, nous avons caractérisé les menaces pesant sur les écosystèmes insulaires à l'échelle globale, et prospecté également leurs distributions au sein de différents groupes taxonomiques et régions insulaires. Dans une deuxième partie, nous avons analysé l'incidence des menaces sur la biodiversité endémique insulaire et en particulier sur la composante fonctionnelle. Dans une troisième partie, nous avons identifié les régions insulaires à forte représentativité de la biodiversité endémique menacée au travers de différentes facettes et prospecté leurs niveaux de protection via les aires protégées et les menaces les affectant. Dans une dernière partie, nous avons étudié la vulnérabilité future des îles et de la biodiversité endémique face au changement climatique à l’échéance 2050. À la lumière de nos résultats (identification de menaces majeures dont l'importance varie suivant les groupes taxonomiques, les régions insulaires et également les dimensions de biodiversité considérées), nous avons discuté de l’implication des changements globaux pour la biodiversité endémique insulaire dans un contexte de conservation. Cette thèse révèle l’importance d’intégrer de multiples menaces (et leurs associations) et dimensions de diversité pour les approches de changements globaux et de conservationGlobal changes, because of human activities, are associated with numerous population declines and species extinctions, which are especially pronounced in island systems. The important biodiversity of such ecosystems is particularly vulnerable to anthropogenic pressures because of several characteristics (e.g. island syndrome, low functional redundancy, island geographical isolation). Despite this increased vulnerability, few studies have so far looked at these systems as a study model for assessing patterns of threats to the different facets of diversity (taxonomic, functional, and phylogenetic). However, such work would improve our understanding of islands threats. In this sense, the aim of this PhD thesis is to describe patterns of insular endemic diversity in the current context of global changes and in a future climate change context, by exploring different facets of diversity. The purpose of this work is to highlight potential conservation priorities for these particularly vulnerable ecosystems. We have addressed all of this thesis work on a large scale using two databases of worldwide islands and endemic species. In a first part, we characterized threats to island ecosystems at a global scale and also explored their distributions within different taxonomic groups and island regions. In a second part, we analyzed the impact of threats on the functional component of island endemic biodiversity. In a third part, we have identified priority areas for insular endemic biodiversity representativeness and conservation across different dimensions of biodiversity and explored their levels of protection through protected areas and threats affecting them. In a last part, we studied the future vulnerability of islands and endemic biodiversity to climate change by 2050 based on endemic mammals. In the light of our results (identification of major threats whose importance varies according to the taxonomic groups, the island regions and also the dimensions of biodiversity considered), we discussed the implications of global changes for island endemic biodiversity in a conservation context. This PhD thesis reveals the importance of integrating multiple threats and diversity dimensions for global changes and conservation approaches