Search results for "Visual Perception"
showing 10 items of 387 documents
The context effect in face matching: Effects of feedback.
2011
AbstractFaces are perceived holistically, even when they are presented briefly (Hole, 1994; Richler, Mack, et al., 2009). Results obtained with a context congruency paradigm support dominance of holistic processing for brief timings, but indicate that larger viewing times enable observers to regulate contextual influences, and to use a feature selective focus (Meinhardt-Injac, Persike, & Meinhardt, 2010). Here we provide further evidence for this claim, and illuminate the role of feedback. With trial by trial feedback observers show poor performance in incongruent facial contexts at brief timings, but become quite effective in suppressing information that interferes with the correct judgeme…
Developmental changes in the microgenesis of face perception revealed by effects of context and inversion
2011
AbstractPresent studies on the development of face perception mechanisms are ambiguous about the question of whether holistic face vision arises early, or in the second decade of life (Crookes & McKone, 2009). Measuring the time course of face matching we assess effects of context and inversion as correlates of holistic processing in the microgenesis of face perception within the first 650ms, and compare among 8- to 10-year-old children and adults. Results for adults indicate dominance of holistic viewing at brief timings, which is gradually replaced by feature selective strategies enabling them to selectively attend either internal or external features, as demanded by instruction. For chil…
Embedded word priming elicits enhanced fMRI responses in the visual word form area.
2018
Lexical embedding is common in all languages and elicits mutual orthographic interference between an embedded word and its carrier. The neural basis of such interference remains unknown. We employed a novel fMRI prime-target embedded word paradigm to test for involvement of a visual word form area (VWFA) in left ventral occipitotemporal cortex in co-activation of embedded words and their carriers. Based on the results of related fMRI studies we predicted either enhancement or suppression of fMRI responses to embedded words initially viewed as primes, and repeated in the context of target carrier words. Our results clearly showed enhancement of fMRI responses in the VWFA to embedded-carrier …
The limits of visual mass perception
2009
The theory of direct perception suggests that observers can accurately judge the mass of a box picked up by a lifter shown in a point-light display. However, accurate perceptual performance may be limited to specific circumstances. The purpose of the present study was to systematically examine the factors that determine perception of mass, including display type, lifting speed, response type, and lifter's strength. In contrast to previous research, a wider range of viewing manipulations of point-light display conditions was investigated. In Experiment 1, we first created a circumstance where observers could accurately judge lifts of five box masses performed by a lifter of average strength…
Unconscious integration of multisensory bodily inputs in the peripersonal space shapes bodily self-consciousness
2017
International audience; Recent studies have highlighted the role of multisensory integration as a key mechanism of self-consciousness. In particular, integration of bodily signals within the peripersonal space (PPS) underlies the experience of the self in a body we own (self-identification) and that is experienced as occupying a specific location in space (self-location), two main components of bodily self-consciousness (BSC). Experiments investigating the effects of multisensory integration on BSC have typically employed supra-threshold sensory stimuli, neglecting the role of unconscious sensory signals in BSC, as tested in other consciousness research. Here, we used psychophysical techniq…
Centre-embedded structures are a by-product of associative learning and working memory constraints: Evidence from baboons (Papio Papio)
2012
International audience; Influential theories have claimed that the ability for recursion forms the computational core of human language faculty distinguishing our communication system from that of other animals (Hauser, Chomsky, & Fitch, 2002). In the present study, we consider an alternative view on recursion by studying the contribution of associative and working memory processes. After an intensive paired-associate training with visual shapes, we observed that baboons spontaneously ordered their responses in keeping with a recursive, centre-embedded structure. This result suggests that the human ability for recursion might partly if not entirely originate from fundamental processing cons…
Trains with a view to sickness
2001
This study was supported by Region Rhone-Alpes (contract ARASSH n°L099552501) and CEC Improving Human Potential: Access to Research Infrastructures HPRI-1999-CT-00025.
Benton visual form discrimination test in healthy children: normative data and qualitative analysis
2018
The attention evaluation may be considered a crucial phase in neuropsychological assessment. It must take into account the systemic nature of the attentional functions and must use different reliable tests in relation to the neurological and attentional problems to be addressed. The aim of the study was to offer the clinician an effective tool for attention assessment and provide the normative data and performance analysis on the Benton Visual Form Discrimination Test on an Italian sample (number 323) of healthy school children, from ages 5 to 11. Performance on Visual Form Discrimination Test (VFDT) significantly increased with growing age. Performances were significantly different when th…
Ultraviolet vision in lacertid lizards: evidence from retinal structure, eye transmittance, SWS1 visual pigment genes, and behaviour
2014
Abstract Ultraviolet (UV) vision and UV colour patches have been reported in a wide range of taxa and are increasingly appreciated as an integral part of vertebrate visual perception and communication systems. Previous studies with Lacertidae, a lizard family with diverse and complex coloration, have revealed the existence of UV-reflecting patches that may function as social signals. However, confirmation of the signalling role of UV coloration requires demonstrating that the lizards are capable of vision in the UV waveband. Here we use a multidisciplinary approach to characterize the visual sensitivity of a diverse sample of lacertid species. Spectral transmission measurements of the ocula…
Initial information prior to movement onset influences kinematics of upward arm pointing movements
2016
International audience; To elaborate a motor plan and perform online control in the gravity field, the brain relies on priors and multisensory integration of information. In particular, afferent and efferent inputs related to the initial state are thought to convey sensorimotor information to plan the upcoming action. Yet it is still unclear to what extent these cues impact motor planning. Here we examined the role of initial information on the planning and execution of arm movements. Participants performed upward arm movements around the shoulder at three speeds and in two arm conditions. In the first condition, the arm was outstretched horizontally and required a significant muscular comm…