Our everyday world consists of people and objects that are usually specified by dynamic and concurrent auditory and visual attributes, which is known to increase perceptual salience and, therefore, facilitate learning and discrimination in infancy. Interestingly, early experience with faces and vocalizations has two seemingly opposite effects during the first year of life, 1) it enables infants to gradually acquire perceptual expertise for the faces and vocalizations of their own race and, 2) it narrows their ability to discriminate the faces of other-race faces (Kelly et al., 2007). It is not known whether multisensory redundancy might help older infants overcome the other-race effect reported in previous studies. The current project investigated infant discrimination of dynamic and vocalizing other-race faces in younger and older infants using habituation and eye-tracking methodologies. Experiment 1 examined 4-6 and 10-12-month-old infants' ability to discriminate either a native or non-native face articulating the syllable /a/. Results showed that both the 4-6- and the 10-12-month-olds successfully discriminated the faces,regardless of whether they were same- or other-race faces. Experiment 2 investigated the contribution of auditory speech cues by repeating Experiment 1 but in silence. Results showed that only the 10-12-month-olds tested with native-race faces successfully discriminated them. Experiment 3 investigated whether it was speech per se or sound in general that facilitated discrimination of the other-race faces in Experiment 1 by presenting a synchronous, computer-generated "boing" sound instead of audible speech cues. Results indicated that the 4-6-month olds discriminated both types of faces but that 10-12-month-olds only discriminated own-race faces. These results indicate that auditory cues, along with dynamic visual cues, can help infants overcome the effects of previously reported narrowing and facilitate discrimination of other-race static, silent faces. Critically, our results show that older infants can overcome the other race-effect when dynamic faces are accompanied by speech but not when they are accompanied by non- speech cues. Overall, a generalized auditory facilitation effect was found as a result of multisensory speech. Moreover, our findings suggest that infants' ability to process other- race faces following perceptual narrowing is more plastic than previously thought. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection

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.

This research examines how cross-modal and within-modal matching differ. Three broad classes of difference are considered, that crossmodal matching requires (a) "translation" between modality-specific stores or (b) "transformation" of information when different information is available through each modality or (c) transformation, whatever the information available through each modality, owing to differences in encoding strategy. Visual-kinaesthetic matching of the end-point of lever movements has been investigated. It is argued that adult cross-modal performance depends on information and strategy, not directly on modality. Results with children have been less clear, experiments were therefore undertaken, with subjects aged 6-9 years. The hypothesis was that childrens' performance also would be determined by available information, and strategy. With information differences eliminated, modality conditions did not differ in within-subject variability, with up to 20 second unfilled retention intervals. With visual information enhanced by background cues and emphasis of the body midline, visual matching was superior to kinaesthetic, and within-modal was superior to cross-modal matching. These differences disappeared with practice, together with coding relative to the midline in the cross-modal conditions. Midline-relative coding was the norm with the midline emphasised, and without background cues. With or without variability differences, VV did not differ from KK in bias, but KV resulted in greater overshooting, VK greater undershooting. The most likely explanation is resistance to movement when perception is kinaesthetic, causing overestimation of distance moved. Consideration of the information normally available to subjects, generated the hypothesis that temporal and spatial parameters should interact more with kinaesthetic than with visual perception. This was supported, since movement velocity biased only kinaesthetic judgements. It is concluded that matching performance depends on the information encoded and used as the basis of matching, which depends on strategy; strategy depends on information (a) available during stimulus presentation, (b) normally available in each modality, (c) which it is anticipated will be available during response.

The development of species-typical perceptual preferences has been shown to depend on a variety of socially and ecologically derived sensory stimulation during both the pre- and postnatal periods. The prominent mechanism behind the development of these seemingly innate tendencies in young organisms has been hypothesized to be a domain-general pan-sensory selectivity process referred to as perceptual narrowing, whereby regularly experienced sensory stimuli are honed in upon, while simultaneously losing the ability to effectively discriminate between atypical or unfamiliar sensory stimulation. Previous work with precocial birds has been successful in preventing the development of species-typical perceptual preferences by denying the organism typical levels of social and/or self-produced stimulation. The current series of experiments explored the mechanism of perceptual narrowing to assess the malleability of a species-typical auditory preference in avian embryos. By providing a variety of different unimodal and bimodal presentations of a mixed-species vocalizations at the onset of prenatal auditory function, the following project aimed to 1) keep the perceptual window from narrowing, thereby interfering with the development of a species-typical auditory preference, 2) investigate how long differential prenatal stimulation can keep the perceptual window open postnatally, 3) explore how prenatal auditory enrichment effected preferences for novelty, and 4) assess whether prenatal auditory perceptual narrowing is affected by modality specific or amodal stimulus properties during early development. Results indicated that prenatal auditory enrichment significantly interferes with the emergence of a species-typical auditory preference and increases openness to novelty, at least temporarily. After accruing postnatal experience in an environment rich with species-typical auditory and multisensory cues, the effect of prenatal auditory enrichment rapidly was found to rapidly fade. Prenatal auditory enrichment with extraneous non-synchronous light exposure was shown to both keep the perceptual narrowing window open and impede learning in the postnatal environment, following hatching. Results are discussed in light of the role experience plays in perceptual narrowing during the perinatal period.

Perception and recognition of faces are fundamental cognitive abilities that form a basis for our social interactions. Research has investigated face perception using a variety of methodologies across the lifespan. Habituation, novelty preference, and visual paired comparison paradigms are typically used to investigate face perception in young infants. Storybook recognition tasks and eyewitness lineup paradigms are generally used to investigate face perception in young children. These methodologies have introduced systematic differences including the use of linguistic information for children but not infants, greater memory load for children than infants, and longer exposure times to faces for infants than for older children, making comparisons across age difficult. Thus, research investigating infant and child perception of faces using common methods, measures, and stimuli is needed to better understand how face perception develops. According to predictions of the Intersensory Redundancy Hypothesis (IRH; Bahrick & Lickliter, 2000, 2002), in early development, perception of faces is enhanced in unimodal visual (i.e., silent dynamic face) rather than bimodal audiovisual (i.e., dynamic face with synchronous speech) stimulation. The current study investigated the development of face recognition across children of three ages: 5 – 6 months, 18 – 24 months, and 3.5 – 4 years, using the novelty preference paradigm and the same stimuli for all age groups. It also assessed the role of modality (unimodal visual versus bimodal audiovisual) and memory load (low versus high) on face recognition. It was hypothesized that face recognition would improve across age and would be enhanced in unimodal visual stimulation with a low memory load. Results demonstrated a developmental trend (F(2, 90) = 5.00, p = 0.009) with older children showing significantly better recognition of faces than younger children. In contrast to predictions, no differences were found as a function of modality of presentation (bimodal audiovisual versus unimodal visual) or memory load (low versus high). This study was the first to demonstrate a developmental improvement in face recognition from infancy through childhood using common methods, measures and stimuli consistent across age.

No description available.

The present study examined the role of the relationship between the type and amount of prenatal and postnatal stimulus cues in directing the perceptual preferences of bobwhite quail chicks. Results reveal that chicks prefer postnatal stimulus cues that matched the particular type of prenatal stimulation they received as embryos over stimulus cues that match the amount of prenatal stimulus cues they received. Specifically, when chicks were tested with novel stimuli, or when the preference for matching types of stimulus cues was controlled for, chicks exposed to prenatal auditory/visual cues showed a preference for combined auditory/visual cues over auditory cues presented alone. These findings suggest that exposure to enhanced prenatal auditory/visual stimulation can accelerate chicks perceptual responsiveness. However, this effect can be masked depending upon the relationship between the specific type of auditory stimulus cues used during prenatal exposure and subsequent postnatal testing. Further results indicate that preference for familiar type of stimuli can account for why exposure to enhanced prenatal stimulation does not always appear to accelerate responsiveness to combined auditory/visual cues. Therefore, studies examining the effects of prenatal sensory manipulations on postnatal perceptual responsiveness must take into account the specific nature of the relationship between the type and amount of prenatal and postnatal stimulus cues employed in the experiment. In a more general sense, these results suggest that the study of early perceptual development requires the incorporation of complex, dynamic, and hierarchically based notions about the mechanisms associated with behavioral development. / Ph. D.

Doctorat en sciences psychologiques / info:eu-repo/semantics/nonPublished

La naissance prématurée se caractérise par des expériences multisensorielles et sensorimotrices atypiques lors d’une période du développement très sensible à ces dernières (Koenig-Zores & Kuhn, 2016). Les recherches ont mis en évidence un impact significatif de la prématurité sur le développement des enfants (Marret et al., 2015) induisant notamment des troubles perceptivo-moteurs avec ou sans troubles neurologiques associés (De Rose et al., 2013). Cependant, si beaucoup d’études portent sur la motricité des nouveau-nés et nourrissons nés prématurés, peu de données existent sur le développement perceptivo-moteur des enfants nés prématurés sans diagnostic de trouble neurodéveloppemental. La question principale abordée dans cette thèse est de savoir si la prématurité n’induit pas des signatures motrices spécifiques, même en absence de ces troubles. Dans l’objectif de répondre à cette question, différents tests standardisés, et trois tâches expérimentales impliquant la perception des équivalences intermodalitaires, la coordination visuomotrice et le contrôle postural, ont été proposés à 48 enfants nés à terme et 32 enfants nés grands prématurés sans diagnostic de trouble neurodéveloppemental et tous âgés de 8 ans. Les résultats ont mis en évidence dans les deux groupes des habiletés comparables de perception des équivalences intermodalitaires dans les modalités haptique et visuelle. Cependant, ils ont aussi révélé une efficience moindre de la coordination visuomotrice et du contrôle postural chez les enfants nés prématurés en comparaison des enfants nés à terme. Ces différences suggèrent des processus perceptivo-moteurs différents chez les enfants nés grands prématurés sans diagnostic de trouble neurodéveloppemental âgés de 8 ans. Ces résultats offrent ainsi de nouvelles perspectives cliniques, notamment d’évaluation plus fine des habiletés perceptivo-motrices, ainsi que de nouveaux questionnements de recherche sur les trajectoires développementales de ces mêmes habiletés et des réseaux neuronaux sous-jacents chez les enfants nés prématurés. / Preterm birth is associated with atypical multisensory and sensorimotor experiences during a period of development sensitive to these experiences (Koenig-Zores & Kuhn, 2016). The studies showed a significant impact of prematurity on children development (Marret et al., 2015), such as perceptual-motor disorders, with or without associated neurological disorders (De Rose et al., 2013). However, even though there are many studies on motor abilities of preterm newborns and preterm infants, little data exists on perceptual-motor development of preterm children without neurodevelopmental disorders. The main question addressed in this thesis is to know whether prematurity does induce specific motor signatures, even in the absence of neurodevelopmental disorders. To answer this question, different standardized tests and three research tasks involving perception of intersensory equivalences, visuomotor coordination, and postural control, have been proposed to 48 full-term children and 32 very preterm children without any diagnosis of neurodevelopmental disorders, all aged 8 years old. The results revealed comparable perception abilities of intersensory equivalences in haptic and visual modalities in the preterm and the full-term groups. However, they also showed a lower efficiency of visuomotor coordination and postural control in the preterm children compared to the full-term children. These observations suggest different perceptual-motor processes in very preterm children without diagnosis of neurodevelopmental disorders at the age of 8. The results offer new clinical opportunities for a more precise evaluation of perceptual-motor abilities, and new research questions about developmental trajectories of perceptual-motor abilities and underlying neuronal networks, in preterm children.