This study explored the critical features of temporal synchrony for the facilitation of prenatal perceptual learning with respect to unimodal stimulation using an animal model, the bobwhite quail. The following related hypotheses were examined: (1) the availability of temporal synchrony is a critical feature to facilitate prenatal perceptual learning, (2) a single temporally synchronous note is sufficient to facilitate prenatal perceptual learning, with respect to unimodal stimulation, and (3) in situations where embryos are exposed to a single temporally synchronous note, facilitated perceptual learning, with respect to unimodal stimulation, will be optimal when the temporally synchronous note occurs at the onset of the stimulation bout. To assess these hypotheses, two experiments were conducted in which quail embryos were exposed to various audio-visual configurations of a bobwhite maternal call and tested at 24 hr after hatching for evidence of facilitated prenatal perceptual learning with respect to unimodal stimulation. Experiment 1 explored if intermodal equivalence was sufficient to facilitate prenatal perceptual learning with respect to unimodal stimulation. A Bimodal Sequential Temporal Equivalence (BSTE) condition was created that provided embryos with sequential auditory and visual stimulation in which the same amodal properties (rate, duration, rhythm) were made available across modalities. Experiment 2 assessed: (a) whether a limited number of temporally synchronous notes are sufficient for facilitated prenatal perceptual learning with respect to unimodal stimulation, and (b) whether there is a relationship between timing of occurrence of a temporally synchronous note and the facilitation of prenatal perceptual learning. Results revealed that prenatal exposure to BSTE was not sufficient to facilitate perceptual learning. In contrast, a maternal call that contained a single temporally synchronous note was sufficient to facilitate embryos’ prenatal perceptual learning with respect to unimodal stimulation. Furthermore, the most salient prenatal condition was that which contained the synchronous note at the onset of the call burst. Embryos’ prenatal perceptual learning of the call was four times faster in this condition than when exposed to a unimodal call. Taken together, bobwhite quail embryos’ remarkable sensitivity to temporal synchrony suggests that this amodal property plays a key role in attention and learning during prenatal development.

The current program of research tests the following main hypotheses: 1) Synesthetic correspondence is an amodal property that serves to bind intersensory signals and manipulating this correspondence between pairs of audiovisual signals will affect performance on a temporal order judgment (TOJ) task; 2) Manipulating emphasis during a TOJ task from spatial to temporal aspects will strengthen the influence of task-irrelevant auditory signals; 3) The degree of dimensional overlap between audiovisual pairs will moderate the effect of synesthetic correspondence on the TOJ task; and 4) There are gaps in current perceptual theory due to the fact that synesthetic correspondence is a potential confound that has not been sufficiently considered in the design of perception research. The results support these main hypotheses. Finally, potential applications for the findings presented here are discussed.

Dans ce travail, nous considérons le cas d'un robot mobile d'intérieur dont l'objectif est de détecter les humains présents dans l'environnement et de se positionner physiquement par rapport à eux, dans le but de mieux percevoir leur état. Pour cela, le robot dispose de différents capteurs (capteur RGB-Depth, microphones, télémètre laser). Des contributions de natures variées ont été effectuées :Classification d'événements sonores en environnement intérieur : La méthode de classification proposée repose sur une taxonomie de petite taille et est destinée à différencier les marqueurs de la présence humaine. L'utilisation de fonctions de croyance permet de prendre en compte l'incertitude de la classification, et de labelliser un son comme « inconnu ».Fusion audiovisuelle pour la détection de locuteurs successifs dans une conversation : Une méthode de détection de locuteurs est proposée dans le cas du robot immobile, placé comme témoin d'une interaction sociale. Elle repose sur une fusion audiovisuelle probabiliste. Cette méthode a été testée sur des vidéos acquises par le robot.Navigation dédiée à la détection d'humains à l'aide d'une fusion multimodale : A partir d'informations provenant des capteurs hétérogènes, le robot cherche des humains de manière autonome dans un environnement connu. Les informations sont fusionnées au sein d'une grille de perception multimodale. Cette grille permet au robot de prendre une décision quant à son prochain déplacement, à l'aide d'un automate reposant sur des niveaux de priorité des informations perçues. Ce système a été implémenté et testé sur un robot Q.bo.Modélisation crédibiliste de l'environnement pour la navigation : La construction de la grille de perception multimodale est améliorée à l'aide d'un mécanisme de fusion reposant sur la théorie des fonctions de croyance. Ceci permet au robot de maintenir une grille « évidentielle » dans le temps comprenant l'information perçue et son incertitude. Ce système a d'abord été évalué en simulation, puis sur le robot Q.bo. / In this work, we consider the case of mobile robot that aims at detecting and positioning itself with respect to humans in its environment. In order to fulfill this mission, the robot is equipped with various sensors (RGB-Depth, microphones, laser telemeter). This thesis contains contributions of various natures:Sound classification in indoor environments: A small taxonomy is proposed in a classification method destined to enable a robot to detect human presence. Uncertainty of classification is taken into account through the use of belief functions, allowing us to label a sound as "unknown".Speaker tracking thanks to audiovisual data fusion: The robot is witness to a social interaction and tracks the successive speakers with probabilistic audiovisual data fusion. The proposed method was tested on videos extracted from the robot's sensors.Navigation dedicated to human detection thanks to a multimodal fusion:} The robot autonomously navigates in a known environment to detect humans thanks to heterogeneous sensors. The data is fused to create a multimodal perception grid. This grid enables the robot to chose its destinations, depending on the priority of perceived information. This system was implemented and tested on a Q.bo robot.Credibilist modelization of the environment for navigation: The creation of the multimodal perception grid is improved by the use of credibilist fusion. This enables the robot to maintain an evidential grid in time, containing the perceived information and its uncertainty. This system was implemented in simulation first, and then on a Q.bo robot.

Os humanos têm enfrentado a escolha entre preferências por traços femininos e masculinos, isto é, entre investimentos diretos (cuidado parental) e indiretos (qualidade genética) na reprodução, respectivamente, o que afeta a percepção de atratividade e indica qualidades biossociais. A FM é influenciada principalmente por hormônios reprodutivos, mas sua percepção é mediada por: 1) contextos biopsicossociais (autopercepção e percepção por terceiros), 2) múltiplos canais de informação (visual e vocal) e/ou 3) ameaças ambientais (patógenos e escassez de recursos). Estudos anteriores possuem limitações, como ausência de clareza quanto à associação entre autopercepção e percepção por terceiros da FM; incongruência nas informações das faces e vozes dos homens; e estudos focando principalmente nas preferências das mulheres por faces e vozes manipuladas digitalmente e usando um modelo de escolha forçada. Assim, examinamos: (a) possíveis associações entre percepções subjetivas (autopercepção e percepção por terceiros da FM e atratividade) e FM medida; (b) concordância na FM de mulheres e homens percebida por terceiros; e (c) influência de patógenos (PT) e escassez de recursos (ER) nas preferências pela FM no sexo oposto. Tiramos fotos faciais e gravamos vozes e danças de público-alvo de 41 mulheres e 38 homens e medimos o dimorfismo sexual da forma facial, a frequência fundamental vocal e o etograma das danças. Estes participantes também autoavaliaram sua FM e atratividade faciais, vocais e comportamentais. Posteriormente, 64 (43 mulheres) e 51 (28 mulheres) estudantes avaliaram respectivamente a FM e atratividade dos estímulos do público-alvo. Com as avaliações da FM escolhemos os cinco mais masculinos e os cinco mais femininos para cada estímulo, dentro de cada sexo. Finalmente, 370 estudantes (206 mulheres) leram um artigo de jornal da condição controle e um dos artigos da condição ambiental (PT ou ER); o artigo PT era sobre o Aedes aegypti, enquanto o artigo ER era sobre a crise econômica brasileira. Os participantes foram aleatoriamente designados para o contexto de relacionamento de curto ou longo prazo. Após cada artigo, os voluntários avaliaram a atratividade dos estímulos do público-alvo individualmente. Cada amostra conteve diferentes estudantes do estado de São Paulo com 18 a 35 anos. As percepções subjetivas das mulheres não refletiram as percepções dos terceiros nem as medidas objetivas. Todavia, a FM facial e 8 vocal delas se correlacionou, sugerindo concordância informacional. Diferentemente, as autoavaliações dos homens e as avaliações de terceiros quanto à FM e atratividade se correlacionaram. Ademais, o tom de voz mais masculino se associou com a FM autodeclarada e declarada por terceiros. Entretanto, as avaliações de terceiros quanto à FM facial e vocal não se relacionaram, indicando mensagens distintas. Além disso, no contexto de longo prazo, as mulheres preferiram um mosaico entre faces masculinas e vozes femininas após a ER. Os homens, por sua vez, preferiram vozes masculinas, sugerindo preferência por parceiros com maior acesso a recursos. Não houve efeito da condição PT no contexto de curto prazo, indicando a influência do modelo experimental. Finalmente, as danças não produziram qualquer efeito, sugerindo um desenvolvimento diferente das faces e vozes / During evolution, humans faced the trade-off between preferences for feminine and masculine traits which are connected to direct (parental care) and indirect (genetic quality) investments into reproduction, respectively. Therefore, femininity-masculinity (FM) affects perceived attractiveness and indicates biosocial qualities. Physiological and morphological FM are primarily influenced by reproductive hormones; however, its perception can be mediated by: 1) biopsychosocial contexts (e.g. self- and other-perception), 2) multiple channels of information (e.g. visual and vocal information), and 3) environmental threats (e.g. pathogens and resource scarcity). However, previous studies show limitations. Firstly, it is unclear if self- and other-rated FM are associated. Secondly, results suggest that womens faces and voices present concordant information about their FM; however, mixed results are found for men. Finally, studies mainly focus on womens preferences for digitally manipulated male faces and voices in a forced-choice design. Thus, we examined: (a) possible associations between subjective perceptions (i.e. self- and other-rated FM and attractiveness), and measured FM; (b) whether womens and mens FM is concordantly perceived by third-party raters; and (c) the influence of pathogen threat (PT) and resource threat (RT) on womens and mens preference for FM in the opposite sex. We took facial photos, and recorded voices and dances of a target sample of 41 women and 38 men and we measured sexual dimorphism of facial shape, vocal fundamental frequency, and ethogram of videos. These participants also self-rated their facial, vocal, and behavioral FM and attractiveness. Later, 64 (43 women) and 51 (28 women) students independently rated facial, vocal and behavioral FM and attractiveness of the target sample, respectively. Finally, 370 (206 women) students were primed with newspaper-like articles on either PT (Aedes aegypti, and its mosquito-borne diseases) or RT (Brazilian economic crisis), and compared to a control condition (lions poisoned in a Kenyan Reserve). Participants were randomly assigned either for a short- or long-term relationship. After each priming article, participants rated attractiveness of the five most masculine and the five most feminine stimuli of the opposite sex of the target sample in a standalone-rating design. Each sample was independent and comprised students, aged 18-35 years, from universities across the state of Sao Paulo, Brazil. In women, results showed that 10 subjective perceptions did not reflect perceptions of others or objective measures. However, womens facial and vocal FM correlated positively, suggesting concordant information about mate quality. In contrast, mens self-rated FM and attractiveness correlated with third-party ratings, and male voice pitch correlated with self- and other-rated FM. Nevertheless, other-ratings on mens FM did not correlated, indicating multiple messages. Finally, for long-term context, women preferred a mosaic of mens masculine faces and feminine voices after primed with RT condition. Men, however, preferred masculine female voices, suggesting a preference for partners with easier access to resources. There was no effect of PT condition in short-term context, indicating the influence of the study design. Finally, no effect was found for dances, suggesting a different development than faces and voices

La capacité humaine de reconnaitre et d’identifier de nombreux individus uniquement grâce à leur voix est unique et peut s’avérer cruciale pour certaines enquêtes. La méconnaissance de cette capacité jette cependant de l’ombre sur les applications dites « légales » de la phonétique. Le travail de thèse présenté ici a comme objectif principal de mieux définir les différents processus liés au traitement des voix dans le cerveau et les paramètres affectant ce traitement. Dans une première expérience, les potentiels évoqués (PÉs) ont été utilisés pour démontrer que les voix intimement familières sont traitées différemment des voix inconnues, même si ces dernières sont fréquemment répétées. Cette expérience a également permis de mieux définir les notions de reconnaissance et d’identification de la voix et les processus qui leur sont associés (respectivement les composantes P2 et LPC). Aussi, une distinction importante entre la reconnaissance de voix intimement familières (P2) et inconnues, mais répétées (N250) a été observée. En plus d’apporter des clarifications terminologiques plus-que-nécessaires, cette première étude est la première à distinguer clairement la reconnaissance et l’identification de locuteurs en termes de PÉs. Cette contribution est majeure, tout particulièrement en ce qui a trait aux applications légales qu’elle recèle. Une seconde expérience s’est concentrée sur l’effet des modalités d’apprentissage sur l’identification de voix apprises. Plus spécifiquement, les PÉs ont été analysés suite à la présentation de voix apprises à l’aide des modalités auditive, audiovisuelle et audiovisuelle interactive. Si les mêmes composantes (P2 et LPC) ont été observées pour les trois conditions d’apprentissage, l’étendue de ces réponses variait. L’analyse des composantes impliquées a révélé un « effet d’ombrage du visage » (face overshadowing effect, FOE) tel qu’illustré par une réponse atténuée suite à la présentation de voix apprise à l’aide d’information audiovisuelle par rapport celles apprises avec dans la condition audio seulement. La simulation d’interaction à l’apprentissage à quant à elle provoqué une réponse plus importante sur la LPC en comparaison avec la condition audiovisuelle passive. De manière générale, les données rapportées dans les expériences 1 et 2 sont congruentes et indiquent que la P2 et la LPC sont des marqueurs fiables des processus de reconnaissance et d’identification de locuteurs. Les implications fondamentales et en phonétique légale seront discutées. / The human ability to recognize and identify speakers by their voices is unique and can be critical in criminal investigations. However, the lack of knowledge on the working of this capacity overshadows its application in the field of “forensic phonetics”. The main objective of this thesis is to characterize the processing of voices in the human brain and the parameters that influence it. In a first experiment, event related potentials (ERPs) were used to establish that intimately familiar voices are processed differently from unknown voices, even when the latter are repeated. This experiment also served to establish a clear distinction between neural components of speaker recognition and identification supported by corresponding ERP components (respectively the P2 and the LPC). An essential contrast between the processes underlying the recognition of intimately familiar voices (P2) and that of unknown but previously heard voices (N250) was also observed. In addition to clarifying the terminology of voice processing, the first study in this thesis is the first to unambiguously distinguish between speaker recognition and identification in terms of ERPs. This contribution is major, especially when it comes to applications of voice processing in forensic phonetics. A second experiment focused more specifically on the effects of learning modalities on later speaker identification. ERPs to trained voices were analysed along with behavioral responses of speaker identification following a learning phase where participants were trained on voices in three modalities : audio only, audiovisual and audiovisual interactive. Although the ERP responses for the trained voices showed effects on the same components (P2 and LPC) across the three training conditions, the range of these responses varied. The analysis of these components first revealed a face overshadowing effect (FOE) resulting in an impaired encoding of voice information. This well documented effect resulted in a smaller LPC for the audiovisual condition compared to the audio only condition. However, effects of the audiovisual interactive condition appeared to minimize this FOE when compared to the passive audiovisual condition. Overall, the data presented in both experiments is generally congruent and indicate that the P2 and the LPC are reliable electrophysiological markers of speaker recognition and identification. The implications of these findings for current voice processing models and for the field of forensic phonetics are discussed.