Neural correlates of eye-gaze detection in young children with autism.

Various reports have demonstrated difficulties in eye-gaze processing in older children and adults with autism. However, little is known about the neural or developmental origin of such difficulties. In the present study, we used high-density Event-Related Potentials (HD-ERPs) to record the neural correlates of gaze processing in young children with autism, and their age-matched controls.

Processes of change in brain and cognitive development.

We review recent advances in the understanding of the mechanisms of change that underlie cognitive development. We begin by describing error-driven, self-organizing and constructivist learning systems. These powerful mechanisms can be constrained by intrinsic factors, other brain systems and/or the physical and social environment of the developing child.

Eye gaze cueing facilitates neural processing of objects in 4-month-old infants.

A major issue in developmental science is how infants use the direction of other's eye gaze to facilitate the processing of information. Four-month-old infants passively viewed images of an adult face gazing toward or away from objects. When presented with the objects a second time, infants showed differences in a slow wave event-related potential, indicating that uncued objects were perceived as less familiar than objects previously cued by the direction of gaze of another person.

Mechanisms of eye gaze perception during infancy.

Previous work has shown that infants are sensitive to the direction of gaze of another's face, and that gaze direction can cue attention. The present study replicates and extends results on the ERP correlates of gaze processing in 4-month-olds. In two experiments, we recorded ERPs while 4-month-olds viewed direct and averted gaze within the context of averted and inverted heads.

Face-sensitive cortical processing in early infancy.

Background: Debates about the developmental origins of adult face processing could be directly addressed if a clear infant neural marker could be identified. Previous research with infants remains open to criticism regarding the control stimuli employed.

Methods: We recorded ERPs from adults and 3-month-old infants while they watched faces and matched visual noise stimuli.

Maternal personality and infants' neural and visual responsivity to facial expressions of emotion.

Background: Recent investigations suggest that experience plays an important role in the development of face processing. The aim of this study was to investigate the potential role of experience in the development of the ability to process facial expressions of emotion.

Method: We examined the potential role of experience indirectly by investigating the relationship between the emotional environment provided by mothers (as indexed by affective measures of their personality) and 7-month-olds' processing of emotional expressions (as indexed by visual attention and event-related potentials [ERPs]).

Development of human brain functions.

Aspects of postnatal human brain development are reviewed. The development of brain function has commonly been characterized in terms of the unfolding of a maturational sequence. In contrast, we argue that postnatal functional brain development occurs through a dynamic process of emerging patterns of interactions between different brain regions.

Representing occluded objects in the human infant brain.

One of the most striking phenomena in cognitive development has been the apparent failure of infants to show 'object permanence' in manual reaching tasks although they show evidence for representing hidden objects in studies measuring looking times. We report a neural correlate of object permanence in six-month-old infants: a burst of gamma-band EEG activity over the temporal lobe that occurs during an occlusion event and when an object is expected to appear from behind an occluder. We interpret this burst as being related to the infants' mental representation of the occluded object.

Development of face-sensitive event-related potentials during infancy: a review.

Event-related potential (ERP) studies in adults have identified a number of components related to encoding and recognition memory of faces. Although behavioural studies indicate that even very young infants are able to detect faces and recognise familiar individuals, very few ERP studies document the neural correlates of these early abilities. In this article, we review four components (P1, N290, P400, Nc) and slow wave activity that are elicited while infants view faces.

ERP abnormalities of illusory contour perception in Williams syndrome.

Williams syndrome is a genetic disorder in which visuo-spatial performance is poor. Theorists have claimed that the deficit lies in high-level processing, leaving low-level visual processes intact. We investigated this claim by examining an aspect of low-level processing, perceptual completion, i.

Infants perceiving and acting on the eyes: tests of an evolutionary hypothesis.

It has been hypothesized that an evolutionarily ancient mechanism underlies the ability of human infants to detect and act upon the direction of eye gaze of another human face. However, the evidence from behavioral studies with infants is also consistent with a more domain-general system responsive to the lateral motion of stimuli regardless of whether or not eyes are involved. To address this issue three experiments with 4-month-old infants are reported that utilize a standard face-cueing paradigm.

The "what" and "where" of object representations in infancy.

Four-month-olds' memory for surface feature and location information was tested following brief occlusions. When the target objects were images of female faces or monochromatic asterisks infants showed increased looking times following a change in identity or color but not following a change in location or combinations of feature and location information. When the target objects were images of manipulable toys, the infants showed increased looking times following a change in location but not identity or the binding of location and identity information.

Spatial representation and attention in toddlers with Williams syndrome and Down syndrome.

The nature of the spatial representations that underlie simple visually guided actions early in life was investigated in toddlers with Williams syndrome (WS), Down syndrome (DS), and healthy chronological age- and mental age-matched controls, through the use of a "double-step" saccade paradigm. The experiment tested the hypothesis that, compared to typically developing infants and toddlers, and toddlers with DS, those with WS display a deficit in using spatial representations to guide actions. Levels of sustained attention were also measured within these groups, to establish whether differences in levels of engagement influenced performance on the double-step saccade task.

Neuroimaging of typical and atypical development: a perspective from multiple levels of analysis.

To date, research involving functional neuroimaging of typical and atypical development has depended on several assumptions about the postnatal maturation of the brain. We consider evidence from multiple levels of analysis that brings into question these underlying assumptions and advance an alternative view. This alternative view, based on an "interactive specialization" approach to postnatal brain development, indicates that there is a need to: obtain data from early in development; focus more on differences in interregional interactions rather than searching for localized, discrete lesions; examine the temporal dynamics of neural processing; and move away from deficits to image tasks in which atypical participants perform as well as typically developing participants.

Eye contact detection in humans from birth.

Making eye contact is the most powerful mode of establishing a communicative link between humans. During their first year of life, infants learn rapidly that the looking behaviors of others conveys significant information. Two experiments were carried out to demonstrate special sensitivity to direct eye contact from birth.

Specialization of neural mechanisms underlying face recognition in human infants.

Newborn infants respond preferentially to simple face-like patterns, raising the possibility that the face-specific regions identified in the adult cortex are functioning from birth. We sought to evaluate this hypothesis by characterizing the specificity of infants' electrocortical responses to faces in two ways: (1) comparing responses to faces of humans with those to faces of nonhuman primates; and 2) comparing responses to upright and inverted faces. Adults' face-responsive N170 event-related potential (ERP) component showed specificity to upright human faces that was not observable at any point in the ERPs of infants.

Developing a brain specialized for face perception: a converging methods approach.

Adults are normally very quick and accurate at recognizing facial identity. This skill has been explained by two opposing views as being due to the existence of an innate cortical "face module" or to the natural consequence of adults' extensive experience with faces. Neither of these views puts particular importance on studying development of face-processing skills, as in one view the module simply comes on-line and in the other view development is equated with adult learning.

Global-Before-Basic Object Categorization in Connectionist Networks and 2-Month-Old Infants.

A 3-layered backpropagation connectionist network, configured as an autoassociator, learned to form global (e.g., mammal) before basic-level (e.

Dynamic Plasticity Influences the Emergence of Function in a Simple Cortical Array.

In computational experiments with a simplified cortical array we investigated the factors that give rise to the functional organization of the cerebral cortex during brain development. We show that a dynamical spatial modulation of plasticity in the substrate (i.e.