Spatiotemporal Regularity and Interevent Contingencies as Information for Infants' Visual Expectations

This study examined infants' use of picture‐location contingencies and spatiotemporal regularity in forming visual expectations. Ninety‐six 3‐month‐olds watched an event sequence in which pictures appeared at 3 locations, either in regular left‐center‐right alternation or in a random center‐side pattern. For half of the infants, the content of the central picture was predictive of the location of the upcoming peripheral event. Analyses of anticipations and interpicture fixation shifts revealed that both spatiotemporal regularity and consistent interevent contingencies fostered increased anticipation of peripheral pictures. The type of spatiotemporal sequence that infants observed also differentially biased their responses to test trials that followed the picture sequence: Infants who experienced regular alternation sequences continued the side‐to‐side pattern during the 2‐choice test trials, whereas infants who experienced irregular sequences looked back to the location of the previous picture. Stable interevent contingencies, in contrast, did not bias infants' responses toward the contingent side during the choice test trials.     

Anticipatory Eye Movements Reveal Infants' Auditory and Visual Categories

We introduce a new paradigm for the assessment of auditory and visual categories in 6‐month‐old infants using a 2‐alternative anticipatory eye‐movement response. Infants were trained by 2 different methods to anticipate the location of a visual reinforcer at 1 of 2 spatial locations (right or left) based on the identity of 2 cuing stimuli. After a training phase, infants were presented with a series of generalization trials in which novel (untrained) stimuli served as the cue to the anticipatory eye movement. Four experiments illustrated that infants can learn the 2‐choice discriminative response during training. Infants also showed anticipatory eye movements to novel stimuli, indicating sensitivity to variations along a variety of stimulus dimensions (e.g., color, shape, orientation, spatial frequency, pitch, and duration). In addition, the paradigm can be used to assess categorization in individual infants, thereby revealing the stimulus dimensions to which infants naturally attend.     

Behavioral and Cortical Measures of Infants' Visual Expectations

Features of the habituation paradigm were combined with the visual expectation paradigm to examine behavioral and cortical indexes of infants' visual expectations. Eight 3‐month‐old infants watched an alternating picture sequence while their eye movements were videotaped and their cortical electrophysiological activity (event‐related potential [ERP]) was recorded. Two ERP epochs were examined: a 3,000‐msec stimulus‐locked epoch included 1,000 msec before stimulus onset through 1,000 msec after stimulus offset; and a 1,200‐msec response‐locked epoch included 700 msec before saccade onset through 500 msec after the saccade. All infants anticipated upcoming pictures, and eye movement latencies for pictures that were not anticipated were comparable to saccade latencies reported in other visual expectation studies of infants at this age. Three components were identified in the stimulus‐locked ERP waveform: a slowly developing negativity prior to picture onset, a postonset negative slow wave, and a late negative deflection that peaked about 750 msec after picture onset. All stimulus‐locked components were larger for familiar than for unfamiliar pictures; prestimulus negativity was also greater before anticipated pictures. The response‐locked waveform contained 2 prominent features: a slowly increasing negative shift (NS) that began about 500 msec before saccade onset and a positive presaccadic potential that occurred about 30 to 90 msec before the saccade. Response‐locked components were larger for anticipatory saccades at the frontal scalp site; for reactive saccades, response‐locked components were larger at the vertex. Results are informative about ERPs in infants, cortical control of eye movements, and the development of visual expectations.     

ACKNOWLEDGMENT OF GUEST REVIEWERS

This study explored 14‐month‐old infants' ability to form novel word‐spatial relation associations. During habituation, infants heard 1 novel word (e.g., teek) while viewing dynamic containment events (i.e., Big Bird placed in a box) and, on other habituation trials, a second novel word (e.g., blick) while viewing dynamic support events (i.e., Big Bird placed on the box). Each novel word was presented in a sentence (e.g., “She's putting Big Bird teek the box”). During the test, infants discriminated an event that maintained the habituation word‐relation pairing from one that presented a switch in this pairing. The results indicate that 14‐month‐olds can learn to form word‐relation associations quickly, requiring only a few minutes of experience with each word‐relation pairing.     

Infants' ERP Responses to Novel and Familiar Stimuli Change Over Time: Implications for Novelty Detection and Memory

Detection of novelty is an important cognitive ability early in development, when infants must learn a great deal about their world. Work with adults has identified networks of brain areas involved in novelty detection; this study investigated electrophysiological correlates of detection of novelty and recognition of familiarity in 9‐month‐old infants, using event‐related potentials (ERPs). Infants were familiarized with an event in the laboratory, then ERPs were recorded as they viewed repeated presentations of pictures of this familiar event and a novel event, along with single presentations of 30 trial‐unique events. A middle‐latency negative component was sensitive to degree of novelty, differing in amplitude and latency by stimulus condition and across repeated presentations. Long‐latency slow‐wave activity also related to stimulus condition. Findings have implications for our understanding of infants' detection of novel information and the processes that render the novel familiar.     

Relative Color Contrast Drives Competition in Early Exogenous Orienting

Young infants typically orient to a moving object, but the strength of this tendency depends on what else is in the visual field, with some objects competing for attention more effectively than others. This competition was studied in 3.5‐month‐old infants by manipulating the colors and spatial distributions of static elements that appeared with a small moving probe. The hypothesis was that the competition from these static bars would depend on their color contrasts. Three different color pairings were used: red with green, pink with green, and red with pink. The results were generally consistent with the hypothesis that the competition from static elements in the visual field depends on their color contrasts. Orienting at 3.5 months is determined by competition mechanisms that weight motion and color and most probably other stimulus characteristics to produce a directional response.     

Differential Frontal Cortex Activation Before Anticipatory and Reactive Saccades in Infants

Neural correlates of anticipatory and reactive saccades were studied in 4‐month‐old infants by recording high‐density event‐related potentials. Infants were presented with a fixed sequence of stimulus presentation to which they rapidly showed anticipatory saccades, as well as continuing with some reactive (stimulus‐driven) saccades. As in a previous study, no clear evidence was found for adultlike, saccade‐related potentials, although some presaccadic differences between reactive and anticipatory saccades were observed. Infants also showed different stimulus offset‐related effects preceding the 2 types of trials with a right‐frontal positivity when an anticipatory look follows, but only left‐frontal positivity when a reactive saccade follows.     

2½‐Year‐Old Children Use Animacy and Syntax to Learn a New Noun

We examine how attention to animacy information may contribute to children's developing knowledge of language. This research extends beyond prior research in that children were shown dynamic events with novel entities, and were asked not only to comprehend sentences but to use sentence structure to infer the meaning of a new word. In a 4 × 3 design, animacy status (e.g., animate agent, inanimate patient) and labeling syntax (agent, patient, nonlabel control) were varied. Across most events, 2 1/2‐year‐old participants responded as if they expected animate entities to be named. However, in a prototypical (animate agent‐inanimate patient) event condition, children responded differentially across different syntactic structures. Thus, the clearest evidence for attention to syntactic cues was found in the prototypical event condition. These results suggest that young children attend to the animacy status of unfamiliar entities, that they have expectations about animacy relations in events, and that these expectations support emerging syntactic knowledge.     

Sex Differences in Infants' Ability to Represent Complex Event Sequences

Prior research suggests that when very simple event sequences are used, 4.5‐month‐olds demonstrate the ability to individuate objects based on the continuity or disruption of their speed of motion (Wilcox & Schweinle, 2003). However, infants demonstrate their ability to individuate objects in an event‐monitoring task (i.e., infants must keep track of an ongoing event) at a younger age than in an event‐mapping task (i.e., infants must compare information from 2 different events). The research presented here built on these findings by examining infants' capacity to succeed on an event‐mapping task with a more complex event sequence to determine if the complexity of the event interferes with their ability to form summary representations of the event, and, in short, individuate the objects. Three experiments were conducted with infants 4.5 to 9.5 months of age. The results indicated that (a) increasing the complexity of the objects' trajectories adversely affected infants' performance on the task, and (b) boys were more likely to succeed than girls. These findings shed light on how representational capacities change during the first year of life and are discussed in terms of information processing and representational capabilities as well as neuro‐anatomical development.     

To Grasp or Not to Grasp: Infants’ Actions Toward Objects and Pictures

We conducted two experiments to address questions over whether 9‐month‐old infants believe that objects depicted in realistic photographs can be picked up. In Experiment 1, we presented 9‐month‐old infants with realistic color photographs of objects, colored outlines of objects, abstract colored “blobs,” and blank pages. Infants most commonly rubbed or patted depictions of all types. They also showed significantly more grasps toward the realistic photographs than toward the colored outlines, blobs, and blank pages, but only 24% of infants directed grasping exclusively at the photographs. In Experiment 2, we further explored infants’ actions toward objects and pictures while controlling for tactile information. We presented 9‐month‐old infants with objects and pictures of objects under a glass cover in a false‐bottom table. Although there were no significant differences between the proportion of rubs and pats infants directed toward the objects versus the photographs, infants exhibited significantly more grasping toward the objects than the photographs. Together, these findings show that 9‐month‐old infants largely direct appropriate actions toward realistic photographs and real objects, indicating that they perceive different affordances for pictures and objects.     

Transfer of Social Learning Across Contexts: Exploring Infants' Attribution of Trait‐Like Emotions to Adults

We explored whether 15‐month‐olds expect another person's emotional disposition to be stable across social situations. In three observation trials, infants watched two adults interact. Half the infants saw one of the adults (“Emoter”) respond negatively to the other adult's actions (Anger group); half saw the Emoter respond neutrally to the same actions (Neutral group). After a change in social context, infants participated in novel tasks with the (now‐neutral) Emoter. Infants in the Anger group were significantly more likely to relinquish desirable toys to the Emoter. We hypothesize that, in the initial observation trials, infants learned that the Emoter was “anger‐prone” and expected her to get angry again in a new social situation. Consequently, infants readily gave the Emoter what she wanted. These findings reveal three key features of infants' affective cognition: (1) infants track adults' emotional history across encounters; (2) infants learn from observing how people interact with others and use this to form expectations about how these people will treat them; and (3) more speculatively, infants use appeasement to cope with social threat. We hypothesize that infants form “trait‐like” attributions about people's emotional dispositions and use this to formulate adaptive responses to adults in novel social contexts.     

Infant Side Biases and Familiarity‐Novelty Preferences During a Serial Paired‐Comparison Task

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 for 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.     

Young Infants' Performance in the Object‐Variation Version of the Above‐Below Categorization Task: A Result of Perceptual Distraction or Conceptual Limitation?

Five experiments were conducted to examine the performance of young infants on above versus below categorization tasks. Experiments 1 and 2 showed that infants did not form abstract categorical representations for above and below when familiarized with different objects depicted in a constant spatial relation relative to a horizontal bar and tested on a novel object depicted in the familiar and novel spatial relation. Experiments 3 through 5 examined perceptual‐attentional distraction versus conceptually based generalization explanations for young infant performance in the object‐variation version of the above‐below categorization task. Experiments 3 and 4 demonstrated that infants still did not form abstract categorical representations for above and below when object variation was removed from the familiarization trials or when object novelty was reduced during the preference test trials. However, Experiment 5 showed that 3‐ and 4‐month‐olds succeeded on the above versus below categorization task when familiarized with object variation and preference tested with a familiar versus novel object‐bar relation. These results indicate that young infants can form categorical representations for above and below in the object‐variation version of the above‐below categorization task, but that such representations are specific to the particular objects presented. Young infant performance in the object‐variation version of the above‐below categorization task thus reflects a conceptually based generalization limit rather than a problem of perceptual‐attentional distraction.     

Pointing as Epistemic Request: 12‐month‐olds Point to Receive New Information

Infants start pointing systematically to objects or events around their first birthday. It has been proposed that infants point to an event to share their appreciation of it with others. In this study, we tested another hypothesis, according to which infants’ pointing could also serve as an epistemic request directed to the adult. Thus, infants’ motivation for pointing could include the expectation that adults would provide new information about the referent. In two experiments, an adult reacted to 12‐month‐olds’ pointing gestures by exhibiting “Informing” or “Sharing” behavior. In response, infants pointed more frequently across trials in the Informing than in the Sharing condition. This suggests that the feedback that contained new information matched infants’ expectations more than mere attention sharing. Such a result is consistent with the idea that not just the comprehension but also the production of early communicative signals is tuned to assist infants’ learning from others.     

14‐month‐olds exploit verbs’ syntactic contexts to build expectations about novel words

During their second year of life, infants develop a rudimentary understanding of grammatical categories based on their knowledge and use of frequent function words. The current study inquired whether, at only 14 months of age, infants can track co‐occurrence patterns between function words and content words (e.g., determiners can precede nouns, and pronouns can precede verbs), and use these previously encountered syntactic contexts to build expectations about which function words can co‐occur with novel words. Using a habituation paradigm, French‐learning 14‐month‐olds were presented with utterances containing two novel words preceded by function words (either two determiners in the Novel Nouns condition or two pronouns in the Novel Verbs conditions). We found that at test, infants looked longer during trials in which the novel words occurred in an unexpected syntactic context (following a pronoun for infants in the Novel Nouns condition and following a determiner for infants in the pooled analysis of the three Novel Verbs conditions). Hence, our results confirm previous findings on infants’ sensitivity to noun contexts and most importantly demonstrate that their sensitivity to the co‐occurrence of verbs with pronouns begins much earlier than previously understood.     

A Cross‐Linguistic Study of Word‐Mapping in 18‐ to 20‐Month‐Old Infants

This study was designed to examine whether infants acquiring languages that place a differential emphasis on nouns and verbs, focus their attention on motions or objects in the presence of a novel word. An infant‐controlled habituation paradigm was used to teach 18‐ to 20‐month‐old English‐, French‐, and Japanese‐speaking infants’ novel words for events. Infants were habituated to two word‐event pairings and then presented with new combinations that involved a familiar word with a new object or motion, or both. Children could map the novel word to both the object and the motion, despite the differential salience of object and motion words in their native language. A control experiment with no label confirmed that both object and motion changes were detectable.     

Pointing to Nothing? Empty Places Prime Infants' Attention to Absent Objects

People routinely point to empty space when referring to absent entities. These points to “nothing” are meaningful because they direct attention to places that stand in for specific entities. Typically, the meaning of places in terms of absent referents is established through preceding discourse and accompanying language. However, it is unknown whether nonlinguistic actions can establish locations as meaningful places, and whether infants have the capacity to represent a place as standing in for an object. In a novel eye‐tracking paradigm, 18‐month‐olds watched objects being placed in specific locations. Then, the objects disappeared and a point directed infants' attention to an emptied place. The point to the empty place primed infants in a subsequent scene (in which the objects appeared at novel locations) to look more to the object belonging to the indicated place than to a distracter referent. The place–object expectations were strong enough to interfere when reversing the place–object associations. Findings show that infants comprehend nonlinguistic reference to absent entities, which reveals an ontogenetic early, nonverbal understanding of places as representations of absent objects.     

The emergence of object‐based visual attention in infancy: A role for family socioeconomic status and competing visual features

The development of spatial visual attention has been extensively studied in infants, but far less is known about the emergence of object‐based visual attention. We tested 3–5‐ and 9–12‐month‐old infants on a task that allowed us to measure infants’ attention orienting bias toward whole objects when they competed with color, motion, and orientation feature information. Infants’ attention orienting to whole objects was affected by the dimension of the competing visual feature. Whether attention was biased toward the whole object or its salient competing feature (e.g., “ball” or “red”) changed with age for the color feature, with infants biased toward whole objects with age. Moreover, family socioeconomic status predicted feature‐based attention in the youngest infants and object‐based attention in the older infants when color feature information competed with whole‐object information.     

Twelve‐Month‐Old Infants’ Sensitivity to Others’ Emotions Following Positive and Negative Events

This study investigated infants’ sensitivity to others’ congruent and incongruent emotional reactions to positive and negative events. Thirty‐six 12‐month‐old infants viewed three distinct interpersonal events (give a toy, break a toy, fight over a toy) followed by an emotional expression (happiness, sadness, anger) that was either congruent or incongruent with the preceding event outcome. The duration of infants' looking toward each emotional reaction was examined. Infants demonstrated sensitivity to incongruent emotional reactions for the give and fight events, representing the earliest evidence to date of emotional sensitivity to negative events.     

Learning Stimulus‐Location Associations in 8‐ and 11‐Month‐Old Infants: Multimodal Versus Unimodal Information

Research on the influence of multimodal information on infants' learning is inconclusive. While one line of research finds that multimodal input has a negative effect on learning, another finds positive effects. The present study aims to shed some new light on this discussion by studying the influence of multimodal information and accompanying stimulus complexity on the learning process. We assessed the influence of multimodal input on the trial‐by‐trial learning of 8‐ and 11‐month‐old infants. Using an anticipatory eye movement paradigm, we measured how infants learn to anticipate the correct stimulus–location associations when exposed to visual‐only, auditory‐only (unimodal), or auditory and visual (multimodal) information. Our results show that infants in both the multimodal and visual‐only conditions learned the stimulus–location associations. Although infants in the visual‐only condition appeared to learn in fewer trials, infants in the multimodal condition showed better anticipating behavior: as a group, they had a higher chance of anticipating correctly on more consecutive trials than infants in the visual‐only condition. These findings suggest that effects of multimodal information on infant learning operate chiefly through effects on infants' attention.