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Manual skills slowly develop throughout infancy and have been shown to create clear views of objects that provide better support for visually sustained attention, recognition, memory, and learning. These clear views may coincide with the development of manual skills, or that social scaffolding supports clear viewing experiences like those generated by toddlers during active object exploration. This study used a head-mounted eye tracker to record 5- to 24-month-olds' object views during repeated mother-infant play sessions (Ns = 18). Results show an early beginning of scaffolding in which parents generate views similar to those of older infants and toddlers, resulting in increased fixations to objects. The finding implicates parents as early scaffolders of object attention and learning. [ABSTRACT FROM AUTHOR]

Both human and nonhuman primate adults use infant-directed facial and vocal expressions across many contexts when interacting with infants (e.g., feeding, playing). This infant-oriented style of communication, known as infant-directed speech (IDS), seems to benefit human infants in numerous ways, including facilitating language acquisition. Given the variety of contexts in which adults use IDS, we hypothesized that IDS supports learning beyond the linguistic domain and that these benefits may extend to nonhuman primates. We exposed 2.5-month- old rhesus macaque infants (N = 15) to IDS, adult-directed speech (ADS), and a non-social control (CTR) during a video presentation of unrelated stimuli. After a 5-or 60-minute delay, infants were shown the familiar video side-by- side with a novel video. Infants exhibited a novelty preference after the 5-minute delay, but not after the 60-minute delay, in the ADS and CTR conditions, and a novelty preference in the IDS condition only after the 60-minute delay. These results are the first to suggest that exposure to IDS affects infants’ long-term memory, even in non-linguistic animals. [ABSTRACT FROM AUTHOR]

Eye movements were recorded as 12-month-olds (n = 15), 4-year-olds (n = 17), and adults (n = 19) watched a 15-min video with sequences of shots conveying continuous motion. The central question was whether, and at what age, viewers anticipate the reappearance of objects following cuts to new shots. Adults were more likely than younger viewers to make anticipatory eye movements. Four-year-olds responded to transitions more slowly and tended to fixate the center of the screen. Infants' eye movement patterns reflected a tendency to react rather than anticipate. Findings are consistent with the hypothesis that adults integrate content across shots and understand how space is represented in edited video. Results are interpreted with respect to a developing understanding of film editing due to experience and cognitive maturation. [ABSTRACT FROM AUTHOR]

Visual exploration in infants and adults has been studied using two very different paradigms: free viewing of flat screen displays in desk-mounted eye-tracking studies and real-world visual guidance of action in head-mounted eye-tracking studies. To test whether classic findings from screen-based studies generalize to real-world visual exploration and to compare natural visual exploration in infants and adults, we tested observers in a new paradigm that combines critical aspects of both previous techniques: free viewing during real-world visual exploration. Mothers and their 9-month-old infants wore head-mounted eye trackers while mothers carried their infants in a forward-facing infant carrier through a series of indoor hallways. Demands for visual guidance of action were minimal in mothers and absent for infants, so both engaged in free viewing while moving through the environment. Similar to screen-based studies, during free viewing in the real world low-level saliency was related to gaze direction. In contrast to screen-based studies, only infants - not adults - were biased to look at people, participants of both ages did not show a classic center bias, and mothers and infants did not display high levels of inter-observer consistency. Results indicate that several aspects of visual exploration of a flat screen display do not generalize to visual exploration in the real world. [ABSTRACT FROM AUTHOR]

Infants' understanding of how their actions affect the visibility of hidden objects may be a crucial aspect of the development of search behaviour. To investigate this possibility, 7-month-old infants took part in a two-day training study. At the start of the first session, and at the end of the second, all infants performed a search task with a hiding-well. On both days, infants had an additional training experience. The 'Agency group' learnt to spin a turntable to reveal a hidden toy, whilst the 'Means-End' group learnt the same means-end motor action, but the toy was always visible. The Agency group showed greater improvement on the hiding-well search task following their training experience. We suggest that the Agency group's turntable experience was effective because it provided the experience of bringing objects back into visibility by one's actions. Further, the performance of the Agency group demonstrates generalized transfer of learning across situations with both different motor actions and stimuli in infants as young as 7 months. [ABSTRACT FROM AUTHOR]

The goal of the current study is to assess the temporal dynamics of vision and action to evaluate the underlying word representations that guide infants' responses. Sixteen-month-old infants participated in a two-alternative forced-choice word-picture matching task. We conducted a moment-by-moment analysis of looking and reaching behaviors as they occurred in tandem to assess the speed with which a prompted word was processed (visual reaction time) as a function of the type of haptic response: Target, Distractor, or No Touch. Visual reaction times (visual RTs) were significantly slower during No Touches compared to Distractor and Target Touches, which were statistically indistinguishable. The finding that visual RTs were significantly faster during Distractor Touches compared to No Touches suggests that incorrect and absent haptic responses appear to index distinct knowledge states: incorrect responses are associated with partial knowledge whereas absent responses appear to reflect a true failure to map lexical items to their target referents. Further, we found that those children who were faster at processing words were also those children who exhibited better haptic performance. This research provides a methodological clarification on knowledge measured by the visual and haptic modalities and new evidence for a continuum of word knowledge in the second year of life. [ABSTRACT FROM AUTHOR]

Purpose To provide population-based normative visual acuity ( VA) by age, in children participating in the Sydney Paediatric Eye Disease Study aged 6 to <72 months. Methods Monocular VA was measured using the Amblyopia Treatment Study ( ATS HOTV) protocol (24 to <72 months). Some children were also tested using linear ETDRS or HOTV log MAR VA charts (30 to <72 months). If unable to perform recognition acuity, the Teller Acuity Cards II ( TAC II) was performed (6 to <42 months). Children with significant refractive error or ocular disease were excluded. Results Improvement in VA with age was shown on all three vision tests (all p < 0.0001). Mean VA using ATS HOTV ( n = 836) was 0.13 log MAR (6/8) at <36 months, which improved to −0.01 (6/6) at 66 to <72 months. Mean ETDRS/ HOTV ( n = 399) VA was 0.26 log MAR (6/11) at <36 months, which improved to 0.1 (6/7.5) at 66 to <72 months. Mean monocular TAC II ( n = 442) was 5.7 cycles/degree (0.72 log MAR) at 6 to <9 months and improved to 12.4 cycles/degree (0.38 log MAR) at age 30 to <33 months. Associations with ATS HOTV VA included prematurity (p = 0.027) and socio economic status ( SES) factors such as home ownership (p = 0.039) and employment of one (p = 0.019) or both parents (p = 0.003). Conclusions VA norms in children improved with age and were different according to the VA test used. Low SES was associated with poorer VA, supporting the need for test specific VA norms to be established for different populations. The ATS HOTV appears to be the best test to use for vision screening due to its lower false positive referral rate. [ABSTRACT FROM AUTHOR]

Pointing, like eye gaze, is a deictic gesture that can be used to orient the attention of another person towards an object or an event. Previous research suggests that infants first begin to follow a pointing gesture between 10 and 13 months of age. We investigated whether sensitivity to pointing could be seen at younger ages employing a technique recently used to show early sensitivity to perceived eye gaze. Three experiments were conducted with 4.5- and 6.5-month-old infants. Our first goal was to examine whether these infants could show a systematic response to pointing by shifting their visual attention in the direction of a pointing gesture when we eliminated the difficulty of disengaging fixation from a pointing hand. The results from Experiments 1 and 2 suggest that a dynamic, but not a static, pointing gesture triggers shifts of visual attention in infants as young as 4.5 months of age. Our second goal was to clarify whether this response was based on sensitivity to the directional posture of the pointing hand, the motion of the pointing hand, or both. The results from Experiment 3 suggest that the direction of motion is necessary but not sufficient to orient infants' attention toward a distal target. Infants shifted their attention in the direction of the pointing finger, but only when the hand was moving in the same direction. These results suggest that infants are prepared to orient to the distal referent of a pointing gesture which likely contributes to their learning the communicative function of pointing. [ABSTRACT FROM AUTHOR]

We monitored changes in looking that emerged when 3- to 6-month-old infants were presented with 48 trials pairing familiar and novel faces. Graphic displays were used to identify changes in looking throughout the task. Many infants exhibited strong side biases produced by infants looking repeatedly in the same direction. Although an overall novelty preference was found for the group, individual infants exhibited brief novelty runs. Few infants began with a familiarity preference. We argue that variable looking patterns emerged during the task from competition between the infants' preference to look to something novel versus their tendency to look back to previous locations. Our data suggest that looking during paired-comparison tasks is a dynamic process dependent on perceptual-motor events happening during the task itself. [ABSTRACT FROM AUTHOR]

Four experiments assessed visual short-term memory capacity in 4- to 13-month-old infants by comparing their looking to changing and nonchanging stimulus streams presented side by side. In each stream, 1 to 6 colored squares repeatedly appeared and disappeared. In changing streams, the color of a different randomly chosen square changed each time the display reappeared; the colors remained the same in nonchanging streams. Infants should look longer at changing streams, but only if they can remember the colors of the squares. The youngest infants preferred changing streams only when the displays contained one object, whereas older infants preferred changing streams when the displays contained up to 4 objects. Thus, visual short-term memory capacity increases significantly across the first year of life. [ABSTRACT FROM AUTHOR]

The present paper aims at studying the relationships between posture, muscle tone and visual attention in 5 month-old infants. To this end, a specially designed seating arrangement made it possible to vary posture while keeping constant the spatial relationship between eyes and stimuli. Five month-olds were placed in the reclining position (30°) or in a more erect position (60°). The more erect the posture, the more difficult it should be for the infant to maintain a straight body axis. Muscle tone was evaluated, and infants distinguished in terms of whether they were hypertonic or hypotonic. It was hypothesised that in a more erect position hypotonic children, who experience more difficulties in maintaining posture, should organise their visual exploration in ways different from those considered to be hypertonic. To test it, pairs of three-dimensional stimuli were presented in the distal visual field for one group (N =48) and in the proximal visual field in another group (N =32) for 2 min in each posture. The dynamical organisation of attention was evaluated through the number and duration of fixations on each target, the number of shifts from one target to the other (alternations) and the number of repetitions (back to the previous target). Results showed that visual behaviour was significantly affected by the distance at which stimuli were presented. Infants spent more time in visual exploration when the object was within reach than when it was out of reach. Although posture was shown to play a role in the organisation of visual exploration, no link with muscle tone was found, a surprising result which is discussed. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The present study was aimed at investigating whether, because of a differential sensitivity between the upper and the lower visual fields, in a visual preference task newborns would orient more frequently and look longer at patterns with a great number of high–contrast areas in the upper or lower visual field. Newborns were presented with three pairs of geometrical stimuli, each composed of a pattern with a greater number of elements in the upper part or a pattern with more elements in the lower part. The results showed a reliable preference for the stimuli that had more elements in the upper than in the lower part. The evidence obtained suggests the possibility that, at birth, the visibility of a stimulus depends not only on its sensory properties, but also on its structural characteristics. [ABSTRACT FROM AUTHOR]

Several models of the development of infant visual attention have used information about neural development. Most of these models have been based on nonhuman animal studies and have relied on indirect measures of neural development in human infants. This article discusses methods for studying a “neurodevelopmental” model of infant visual attention using indirect and direct measures of cortical activity. We concentrate on the effect of attention on eye movement control and show how animal-based models, indirect measurement in human infants, and direct measurement of brain activity inform this model. © 2002 Wiley Periodicals, Inc. Dev Psychobiol 40: 226–236, 2002. DOI 10.1002/dev.10029 [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Colour and facial configuration are both very salient aspects of the visual environment for infants, but may both be selectively processed by the right hemisphere (RHS) and under some conditions may compete for RHS resources. The present investigation assessed the relative potency of facial configuration and colour in the two halves of the visual field for 32 infants (with a mean age of 24 weeks). The infants were familiarized to triads of facial figures presented for 250 ms in the left or right visual field. The faces were all different in colour and facial pattern (expression), but one of them (the target) was shown in an upright orientation while the others (distractors) were inverted. The results of paired-comparison recognition tests indicated that the displays had been initially parsed in terms of configurational category (upright faces versus inverted non-faces) in both visual fields, attesting to the primacy of this categorical distinction in both hemispheres. However, the focus for subsequent encoding reflected marked hemispheric discrepancies, with a left visual field (RHS) bias to target colour (comprising the first evidence of this for infants) and a contrary right visual field [left hemisphere (LHS)] advantage for distractor pattern. Copyright © 2001 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This experiment investigates neonatal intersensory functioning between touch and vision for texture density. The experiment compared manual activity (holding time and hand pressure frequency) recorded on objects in the presence (test period) or absence of visual information (pre-test and post-test periods). Thirty-two babies were assigned to four experimental conditions according to texture density of the objects held and seen during the test period: Objects had either the same (matching conditions) or different (mismatching conditions) texture density information. The results clearly showed that in matching conditions, holding times were systematically increased during the test period. However, hand pressure frequency remained unchanged over the three test periods. In the mismatching conditions, holding times remained unchanged over the three test periods. However, hand pressure frequency systematically changed during the test period according to the texture density of the visual object. These results indicate newborns' capability to compare texture density information across modalities. © 2001 John Wiley & Sons, Inc. Dev Psychobiol 38: 123–132, 2001 [ABSTRACT FROM AUTHOR]

Presents the results of a study in which visual fixation in infants from three to six months of age was examined for its fit to the theory of `attentional inertia.' How the study was conducted; Discussion on the theory of `attentional inertia; Findings of the study.

The article offers information on a study which discusses appropriateness of the use of the corrected age for prematurity exploring developmental domains of the Bayley Scales of Infant Development. Topics discussed include information on neurodevelopmental assessment and treatment at early ages in infants born preterm; observation of delay in maintaining visual attention in infants born preterm; and information on higher need for correction when cognitive abilities are considered.