Search

The aim of the present study was to investigate how perceptual binding and selective attention operate during infants' and adults' visual search of an illusory figure. An eye-tracker system was used to test adults and infants in two conditions: illusory and non-illusory (real). In the illusory condition, a Kanizsa triangle was embedded among distractor pacmen which did not generate illusory contours. In the non-illusory condition, a real triangle was included in the same pacmen's display. The results showed that adults detected both the Kanizsa and the real figure automatically and without focal attention (experiment 1). In contrast, 6-month-old infants showed a pop-out effect only for the real figure (experiment 2). The failure of the illusory figure to trigger infants' attention was not due to infants' inability to perceive the illusory figure per se, as infants preferred the illusory figure over a non-illusory control stimulus in a classical preferential-looking task (experiment 3). Overall, these findings indicate that the illusory Kanizsa triangle triggers visual attention in adults, but not in infants, supporting evidence that at 6 months of age the binding processes involved in the perception of a Kanizsa figure do not operate in an adult-like manner.

This study was aimed at investigating the face preference phenomenon and its underlying mechanisms at 3 months of age. Using an eye-tracker apparatus, Experiment 1 demonstrated that 3-month-olds prefer natural face images to unnatural ones, replicating and extending previous evidence obtained with schematic facelike stimuli. Experiments 2 and 3 showed that the general mechanisms that induce face preference in newborns could not explain the same phenomenon at 3 months of age, when infants are attracted by perceptual cues more specific to faces. This suggests that signs of a process of cognitive specialization are already present in 3-month-olds' visual behavior toward faces. © 2004 Elsevier Inc. All rights reserved.

This study examined newborns' face preference using images of natural and scrambled faces in which the location of the inner features was distorted. The results demonstrate that newborns' face preference is not confined to schematic configurations, but can be obtained also with veridical faces. Moreover, this phenomenon is not produced by a specific bias toward the face geometry, but derives from a domain-general bias toward configurations with more elements in the upper than in the lower half (i.e., top-heavy patterns). These results suggest that it may be unnecessary to assume the existence of a prewired tendency to orient toward the face geometry, and support the idea that faces do not possess a special status in newborns' visual world.

The goal of the study was to provide a direct comparison of newborns' ability to process and store, over a 2min delay, the shape of the internal local elements of schematic facelike and non-facelike patterns. Two experiments were carried out using a visual habituation technique with an infant control procedure. The results demonstrate that newborns discriminated between two schematic facelike and non-facelike configurations that differed exclusively for the shape of the internal local elements (Expt I), and they maintained this discriminative ability even when recognition was tested after a 2min retention interval (Expt 2). The results are consistent with the existence of a general pattern learning mechanism that mediates newborns' ability to acquire information about any pattern, including faces (de Schonen & Mancini, 1995; de Schonen, Mancini, & Liegeois 1998; Johnson, 1997).

Many studies have demonstrated that newborns prefer upright faces over upside-down faces. Based on this evidence, some have suggested that faces represent a special class of stimuli for newborns and there is a qualitative difference between the processes involved in perception of facelike and non-facelike patterns (i.e. structural hypothesis). Others suggest that there is no reason to suppose that faces are different from other patterns, because faces, like any other class of visual stimuli, are subject to filtering by the properties of the visual system (i.e. sensory hypothesis). The core question that will be addressed in the present paper is whether, to manifest itself, face preference requires the unique structure of the face, represented by the relative spatial location of its internal features, or rather some more general properties that other stimuli may also possess. Evidence will be presented supporting the idea that newborns do not respond to facelike stimuli by ‘facedness’ but, rather, by some general structural characteristics that best satisfy the constraints of the immature visual system. Copyright © 2001 John Wiley & Sons, Ltd.

People tend to perceive identical top halves (i.e. above the nose) of two face stimuli as being different when they are aligned with distinct bottom halves. This face composite illusion has been demonstrated almost 20 years ago (Young et al., 1987), and is generally considered as the most compelling evidence that facial features are integrated into a holistic representation. Here, we recorded eye movements during the face composite effect, i.e. when the top and the bottom parts of a composite face stimulus are integrated into a single holistic face representation. The behavioral results showed a strong face composite effect when subjects maintained fixation to the top part of the face stimulus. Fixation sites and eye movements were virtually identical when the top and bottom parts were aligned (composite illusion) or misaligned (no illusion), indicating that holistic face processing can be independent of gaze behavior. These findings reinforce the view that holistic representations of individual faces can be extracted early on from low spatial frequency analysis, independently of overt attention.

The study investigated the origins of the ability to recognize faces despite rotations in depth. Four experiments are reported that tested, using the habituation technique, whether 1-to-3-day-old infants are able to recognize the invariant aspects of a face over changes in viewpoint. Newborns failed to recognize facial perceptual invariances between profile and full-face poses (Experiment 1), and profile and 3/4 poses (Experiment 3). Conversely, newborns recognized the identity of a face through full-face and 3/4 poses (Experiment 2). This result cannot be explained as a consequence of newborns’ inability to discriminate between the full-face and 3/4 points of view (Experiment 4). Overall, evidence was provided that newborns are able to derive a representation of an unfamiliar face that is resilient to a certain degree of rotation in depth, from full-face to 3/4 and vice versa.

Existing data indicate that newborns are able to recognize individual faces, but little is known about what perceptual cues drive this ability. The current study showed that either the inner or outer features of the face can act as sufficient cues for newborns' face recognition (Experiment 1), but the outer part of the face enjoys an advantage over the inner part (Experiment 2). Inversion of the face stimuli disrupted recognition when only the inner portion of the face was shown, but not when the whole face was fully visible or only the outer features were presented (Experiment 3). The results enhance our picture of what information newborns actually process and encode when they discriminate, learn, and recognize faces.

Four experiments are reported that were aimed at elucidating some of the controversial issues concerning the preference for facelike patterns in newborns. The experiments were devised to contrast the original and the revised versions of the sensory hypothesis and the structural hypothesis as accounts of face preference in newborns. Experiments 1A and 1B supported the structural hypothesis by showing a visual preference for the stimulus for which components were located in the correct arrangement for a human face. Experiment 2 supported the sensory hypothesis by showing a visual preference for stimuli that were designed to have the optimal spatial frequency components for the newborn visual system. Experiment 3 showed that babies directed attention to a facelike pattern also when it was presented simultaneously with a nonfacelike stimulus with optimal spatial frequency for the newborn visual system.

It has been proposed that newborns’ preferential orienting to faces is solely controlled by a subcortically mediated orienting mechanism (i.e. Conspec). In contrast, preferential-looking tasks show that face preference at birth manifests itself also with measures that index fixation duration. It is possible, however, that orienting and fixation duration are confounded and only orienting matters. The present study used a revised version of the preferential-looking technique, in which the same stimulus (i.e. a facelike or a non-facelike pattern) was simultaneously presented to both sides of the visual field. Results showed that longer total fixation times on the facelike stimuli resulted from the sum of a greater number of brief fixations, rather than from the sum of a small number of long fixations. These findings support the hypothesis that, for facelike patterns, the duration of infant’s fixation on the stimulus is determined by the nature of the pattern that impinges on the periphery of the visual field, more than by the nature of the pattern that is being looked at.

Two experiments were carried out to demonstrate the existence of a global precedence effect in newborns, as it was found in adults and in 3-4 month old infants. The results demonstrated that, when the two levels of visual information are equally discriminable, newborns showed an asymmetric interference between the two levels. This finding provides evidence for a processing dominance of global over local information.

The aim of the present study is to review the existing literature on Nonnutritive Sucking (NNS ) as a tool for investigating neonatal capabilities. Three research areas where NNS was utilized with newborn and infants are considered: regulation of states, visual scanning, attentional processes. In the light of new reported data concerning the relation between NNS and processing of visual and acoustic information at birth, a comprehensive interpretative framework is presented to explain the apparently contradictory results emerging from the three outlined research fields.