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A fundamental question about the development of communication behavior in early life is how infants acquire adaptive communication behavior that is well-suited to their individual social environment, and how the experience of parent-child communication affects this development. The current study investigated how infants develop communication skills when their parents are visually impaired and cannot see their infants' eye gaze. We analyzed 6-min video recordings of naturalistic interaction between 14 sighted infants of blind parents (SIBP) with (a) their blind parent, and (b) a sighted experimenter. Data coded from these interactions were compared with those from 28 age-matched sighted infants of sighted parents (controls). Each infant completed two visits, at 6-10 months and 12-16 months of age. Within each interaction sample, we coded the function (initiation or response) and form (face gaze, vocalization, or action) of each infant communication behavior. When interacting with their parents, SIBP made relatively more communicative responses than initiations, and used more face gaze and fewer actions to communicate, than did controls. When interacting with a sighted experimenter, by contrast, SIBP made slightly (but significantly) more communicative initiations than controls, but otherwise used similar forms of communication. The differential communication behavior by infants of blind versus sighted parents was already apparent by 6-10 months of age, and was specific to communication with the parent. These results highlight the flexibility in the early development of human communication behavior, which enables infants to optimize their communicative bids and methods to their unique social environment. [ABSTRACT FROM AUTHOR]

Although looking-time methods have long been used to measure infant attention and investigate aspects of cognitive development, steady-state visually evoked potential (SSVEP) measures may be more sensitive or practical in some contexts. Here, we demonstrate habituation of infants' SSVEP amplitudes to a flickering checkerboard stimulus, and recovery of attention upon presentation of a novel checkerboard stimulus. This modulation of SSVEP amplitude was more robust than the modulation of looking time. In addition, we provide evidence of enhanced SSVEPs in response to covertly attended checkerboards flickering in peripheral visual fields, even while infants are fixating a central stimulus. These experiments provide the first evidence of habituation and recovery of infant SSVEP amplitudes, as well as the first evidence of sustained infant covert attention using SSVEPs. SSVEPs may be a sensitive, efficient measure for use in studying early cognitive development, in particular infants' overt and covert attention. [ABSTRACT FROM AUTHOR]

Sensitive responding to others’ emotional body expressions is an essential social skill in humans. Using event-related brain potentials, it has recently been shown that the ability to discriminate between emotional body expressions develops between 4 and 8 months of age. However, it is not clear whether the perception of emotional body expressions in others evokes sensitive brain responses linked to motivational processes in infants. We therefore examined frontal EEC alpha asymmetry in response to dynamic happy and fearful body expressions presented to 4- and 8-month-old infants in 2 orientations (upright and inverted). Our results revealed that only 8-month-olds but not 4-month-olds showed significant differences in their frontal asymmetry responses between emotional expressions when presented in an upright orientation. Specifically, 8-month-old infants showed a greater lateralization to the left hemisphere in response to happy expression, indexing a greater tendency to approach, whereas they showed a greater lateralization to the right hemisphere in response to fearful expressions, indexing a greater tendency to withdraw. These findings provide further support for the notion that infants’ perception of emotion undergoes a developmental tuning during this period in development. Critically, the results suggest that the infant brain becomes sensitive to the motivational significance conveyed by the emotional body expressions. [ABSTRACT FROM AUTHOR]

Previous studies have proposed that humans may be born with mechanisms that attend to conspecifics. However, as previous studies have relied on stimuli featuring human adults, it remains unclear whether infants attend only to adult humans or to the entire human species. We found that 1-month-old infants (n = 23) were able to differentiate between human and monkey infants' faces; however, they exhibited no preference for human infants' faces over monkey infants' faces (n= 24) and discriminated individual differences only within the category of human infants' faces (n = 30). We successfully replicated previous findings that 1-month-old infants (n = 42) preferred adult humans, even adults of other races, to adult monkeys. Further, by 3 months of age, infants (n = 55) preferred human faces to monkey faces with both infant and adult stimuli. Human infants' spontaneous preference for conspecific faces appears to be initially limited to conspecific adults and afterward extended to conspecific infants. Future research should attempt to determine whether preference for human adults results from some innate tendency to attend to conspecific adults or from the impact of early experiences with adults. [ABSTRACT FROM AUTHOR]

Developmental psychologists have devoted significant attention to investigating how children learn from others" actions, emotions, and testimony. Yet most of this research has examined children's socially guided learning about artifacts. The present article focuses on a domain that has received limited attention from those interested in the development of social cognition: food. We begin by reviewing the available literature on infants' and children's development in the food domain and identify situations in which children evidence both successes and failures in their interactions with foods. We focus specifically on the role that other people play in guiding what children eat and argue that understanding patterns of successes and failures in the food domain requires an appreciation of eating as a social phenomenon. We next propose a series of questions for future research and suggest that examining food selection as a social phenomenon can shed light on mechanisms underlying children's learning from others and provide ideas for promoting healthy social relationships and eating behaviors early in development. [ABSTRACT FROM AUTHOR]

A growing number of sex differences in infancy have been reported. One task on which they have been observed reliably is the event-mapping task. In event mapping, infants view an occlusion event involving 1 or 2 objects, the occluder is removed, and then infants see 1 object. Typically, boys are more likely than girls to detect an inconsistency between a 2-object occlusion event and a 1-object display. The current research investigated underlying reasons for this sex difference. Three eye-tracking experiments were conducted with infants at 9 and 4 months (mean age). Infants saw a ball-box or ball-ball occlusion event followed by a 1-ball display; visual scanning of the occlusion event and the 1-ball display was recorded. Older boys were more likely than older girls to visually track the objects through occlusion and more likely to detect an inconsistency between the ball-box event and the 1-ball display. In addition, tracking objects through occlusion was related to infants' scanning of the 1-ball display. Both younger boys and girls failed to track the objects through occlusion and to detect an inconsistency between the ball-box event and the 1-ball display. These results suggest that infants' capacity to track objects through occlusion facilitates extraction of the structure of the initial event (i.e., the number of distinct objects involved) that infants can map onto the final display and that sex differences in the capacity emerge between 4 and 9 months. Possible explanations for how the structure of an occlusion event is extracted and mapped are considered. [ABSTRACT FROM AUTHOR]

We recorded electroencephalogram (EEG; 6-9 Hz) and heart rate (HR) from infants at 5 and 10 months of age during baseline and performance on the looking A-not-B task of infant working memory (WM). Longitudinal baseline-to-task comparisons revealed WM-related increases in EEG power (all electrodes) and EEG coherence (medial frontal-occipital electrode pairs) at both ages. WM-related decreases in HR were only present at 5 months, and WM-related increases in EEG coherence became more localized by 10 months. Regression analyses revealed that baseline-to-task changes in psychophysiology accounted for variability in WM performance at 10 but not 5 months. HR and EEG power (medial frontal and lateral frontal electrodes) were unique predictors of variability in 10-month WM performance. These findings are discussed in relation to frontal lobe development and represent the first comprehensive longitudinal analysis of age-related changes in the behavioral and psychophysiological correlates of WM. [ABSTRACT FROM AUTHOR]

There is evidence that 4.5-month-olds do not always use surface pattern to individuate objects but that they can be primed to attend to pattern differences through select experiences. For example, if infants are first shown events in which the pattern of an object predicts its function (dotted containers pound and striped containers pour), they will attend to pattern differences in a subsequent individuation task. However, 4.5-month-olds must see multiple exemplars of the pound and pour events and view the dotted and striped containers together during the events. These results suggest that it is the formation of event categories, in which pattern is linked to object function, that supports pattern priming and that direct comparison of the exemplars facilitates the extraction of event categories. The present research investigated conditions that support the comparison process in 4.5-month-olds. The results revealed that the comparison process was initiated only when the dotted and striped containers were seen directly adjacent to each other; if the containers sat far apart, so that infants had to shift their gaze to compare them, event categories were not extracted. In addition, it was comparison of the two patterned containers, and not comparison of the two function events, that was critical to the formation of event categories. These results join a growing body of research indicating the importance of comparison to category formation in infants and reveal the impact of categorization and comparison processes on object individuation in infancy. [ABSTRACT FROM AUTHOR]

The ability to individuate objects is one of our most fundamental cognitive capacities. Recent research has revealed that when objects vary in color or luminance alone, infants fail to individuate those objects until 11,5 months. However, color and luminance frequently covary in the natural environment, thus providing a more salient and reliable indicator of distinct objects. For this reason, we propose that infants may be more likely to individuate when objects vary in both color and luminance. Using the narrow-screen task of Wilcox and Baillargeon (1998a), in Experiment I we assessed 7.5-month-old infants' ability to individuate uniformly colored objects that varied in both color and luminance or luminance alone. Experiment 2 further explored the link between color and luminance by assessing infants' ability to use pattern differences that included luminance or color to individuate objects. Results indicated that infants individuated objects only when covariations in color and luminance were used. These studies add to a growing body of literature investigating the interaction of color and luminance in object processing in infants and have implications for developmental changes in the nature and content of infants' object representations. [ABSTRACT FROM AUTHOR]

Four experiments familiarized 6-, 9-, 12-, and 16-month-old infants to a solid block that was repeatedly lowered into a semitransparent container. In test trials the end state, containment, was either compatible or incompatible with the objects' size and position. In Experiment I, infants saw the block and box successively before they observed the end state. This forced infants to attend to each object individually and memorize its size and position while observing the end state. In Experiments 2 and 3, the block and container were shown simultaneously, the block suspended above the container at a distance of either 25 cm (Experiment 2) or 2 cm (Experiment 3). The shorter distance made direct comparison easier to perform. In Experiment 4, the full event was shown in which the block was lowered inside the container from a distance of 25 cm. Infants' perception of containment was related to the visual information that was available. When the event made it easier to grasp the relevant information, infants could perceive whether the block could pass in the container at a progressively younger age. [ABSTRACT FROM AUTHOR]

Two experiments investigated 18-month-olds' understanding of the link between visual perception and emotion. Infants watched an adult perform actions on objects. An emoter then expressed neutral affect or anger toward the adult in response to the adult's actions. Subsequently, infants were given 20 s to interact with each object. In Experiment I, the emoter faced infants with a neutral expression during each 20-s response period but looked at either a magazine or the infant. In Experiment 2, the emoter faced infants with a neutral expression, and her eyes were either open or closed. When the emoter visually monitored infants' actions, the infants regulated their object-directed behavior on the basis of their memory of the emoter' s affect. However, if the previously angry emoter read a magazine (Experiment 1) or closed her eyes (Experiment 2), infants were not governed by her prior emotion. Infants behaved as if they expected the emoter to get angry only if she could see them performing the actions. These findings suggest that infants appreciate how people's visual experiences influence their emotions and use this information to regulate their own behavior. [ABSTRACT FROM AUTHOR]

In 3 experiments, 9-month-old infants' expectations for what distinct count noun labels refer to were investigated. In Experiment I, a box was opened to reveal 2 objects inside during familiarization: either 2 identical objects or 2 different objects. Test trials followed the same procedure, except before the box was opened, the contents were described using 2 distinct labels ("I see a wug! I see a dak!") or the same label twice ("I see a zav! I see a zav!"). Infants who heard a label repeated twice looked longer at 2 different objects versus 2 identical objects, whereas infants who heard 2 distinct labels showed a different pattern of looking. Experiments 2 and 3 presented infants with object pairs that only differed in shape or color, and it was found that infants expected the different-shaped (but not the different-colored) objects to be labeled by distinct count nouns. Because the property of shape is a cue to kind membership and the property of color is not, these results suggest that even at the beginning of word learning, infants may expect distinct labels to refer to distinct kinds of objects. [ABSTRACT FROM AUTHOR]

Young infants have repeatedly been shown to be slower than older infants to shift fixation from a midline stimulus to a peripheral stimulus. This is generally thought to reflect maturation of the neural substrates that mediate the disengagement of attention, but this developmental difference may also be attributable to young infants' slower processing of the midline stimulus. This possibility was tested with 3- and 7-month-old infants in 2 experiments in which the degree of familiarity of the midline stimulus was manipulated across repeated trials. The results of these experiments demonstrated that the processing of midline content does affect infants' ocular latencies to a peripheral stimulus but that developmental differences in such processing do not account for developmental differences in disengagement seen across the 1st year. [ABSTRACT FROM AUTHOR]

Preferential-looking studies suggest that by 2 months of age, infants may have knowledge about some object properties, such as solidity. Manual search studies of toddlers examining these same concepts, however, have failed to provide evidence for the same understanding. Investigators have recently attempted to reconcile this disparity but failed to control for the visual novelty of test outcomes. The current design corrected this problem and also tested toddlers' predictions of the object's location. The task involved the same events and apparatus that have been used in manual search tasks but used looking as the dependent measure. Children looked longer when an agent opened the correct door and found no ball than when an incorrect door was opened to reveal no ball. A 2nd experiment indicated that children's preferential-looking performance did not differ from that in manual search tasks simply because additional response time had been allowed to respond. Previous comparisons of looking versus reaching tested children's postdiction response to an object in an unexpected location, but these findings indicate that toddlers can predict where the object should be. [ABSTRACT FROM AUTHOR]

Investigates the responses of human newborns to decreased sound pressure levels with a localized head-turning habituation procedure. Testing the adequacy of the selective receptor adaptation model; Previous research; Subjects; Procedure and stimuli; Design; Results.