bluuebunny/crossref_metadata_2025 huggingface dataset:
A Global‐to‐Basic Trend in Early Categorization: Evidence From a Dual‐Category Habituation Task
Authors: Younger Barbara A. , Fearing Dru D.
Published: January 2004

A series of 3 experiments are reviewed in which infants between 4 and 10 months of age were familiarized with members of 2 basic‐level object categories. The degree of distinctiveness between categories was varied. Preference tests were intended to determine whether infants formed a single category representation (at a more global level) or 2 basic‐level representations. Across 3 experiments, 10‐month‐old infants appeared to have formed multiple basic‐level categories, whereas younger infants tended to form broader, more inclusive representations. The tendency to form multiple categories was influenced to some extent by category distinctiveness. Whereas 10‐month‐olds formed separate categories for all contrasts, 7‐month‐olds did so only when the 2 familiarized categories were from separate global domains. A perceptual account of the global‐to‐basic shift in early categorization is offered. Task dependencies in early categorization are also discussed.
From Knowledge to Knowing: Real Progress in the Study of Infant Categorization
Authors: Smith Linda B.
Published: January 2004

The four articles in this thematic collection present real progress in the study of infant categorization. In this commentary, I attempt to put that progress in perspective by considering where we have been, where we are now, and where, I believe, we are ready and ought to go.
Six‐Month‐Olds' Detection of Clauses Embedded in Continuous Speech: Effects of Prosodic Well‐Formedness
Authors: Nazzi Thierry , Kemler Nelson Deborah G. , Jusczyk Peter W. , Jusczyk Ann Marie
Published: January 2004

Three experiments investigated the role of prosodic structure for infants' recognition of embedded word sequences. Six‐month‐olds were familiarized with 2 versions of the same sequence, 1 corresponding to a well‐formed prosodic unit and the other to a prosodically ill‐formed sequence (although a successive word series). Next, infants heard 2 test passages. One included the well‐formed unit, and the other included the ill‐formed sequence. In Experiment 1, infants listened longer to the passage containing the well‐formed unit, suggesting that such units, even when they are embedded, are better recognized. Experiments 2 and 3 showed that this better recognition does not depend on an acoustic match between the familiarized sequences and their later embeddings. This suggests that the advantage of the well‐formed unit is at least partially due to infants' use of prosody to parse continuous speech.
Spatially Specific Changes in Infants' Muscle Coactivity as They Learn to Reach
Authors: Spencer John P. , Thelen Esther
Published: January 2004

Infants first reach out and touch objects between the ages of 3 and 5 months. This article reports changes in muscle coactivity associated with this transition. A group of 4 infants were observed weekly from 3 to 30 weeks and every 2 weeks from 30 to 52 weeks. Hand kinematics of both prereaching and reaching movements were collected, as was electromyographic activity from the trapezius, deltoid, biceps, and triceps. Before infants first reached for toys presented at midline, they used biceps and triceps to move their hands near the toy in front of them and 45° to the side of midline. After the transition, they used trapezius and deltoid to move the hand toward the toy and combinations of multiple muscles when their arms were high and extended near the toy. Thus, infants showed a dramatic change in which muscles worked together across the transition to reaching, even though their hands moved in similar spatial regions.
Competition for Infants' Attention: The Interactive Influence of Attentional State and Stimulus Characteristics
Authors: Oakes Lisa M. , Tellinghuisen Donald J. , Tjebkes Terri L.
Published: January 2004

The interactive effects of stimulus characteristics and attentional state on infants' distraction latency were studied. As 7‐month‐old infants explored initial stimuli that were composed of either a single nonmoving component or multiple moving components, one of several types of distractors was presented in the periphery. Infants' distraction latencies (the amount of time they took to turn from the initial stimulus to the distractor) varied as a function of the interaction between the infants' attentional state at distractor onset and the characteristics of the stimuli. Variations in the visual characteristics of the distractor stimulus (solid rectangle vs. checkerboard) had a larger effect on distraction latency when infants were in a focused attentional state than when they were in a casual attentional state. Similarly, variations in the auditory characteristic of the distractor stimulus (1 intermittent tone vs. 2 alternating tones) had a larger effect when infants were engaged in a focused attentional state toward the multicomponent toys. Thus, infants' distractibility in this context reflects an interaction between the infants' attentional state and the competition between external stimuli for their attentional focus.
Infants' Looking at Possible and Impossible Screen Rotations: The Role of Familiarization
Authors: Schilling Thomas H.
Published: January 2004

The effects of familiarization and age were examined using Baillargeon's rotating screen paradigm. In Condition A, 4‐month‐olds exposed to 7 180° familiarization trials looked significantly longer at the 180° test events than the 112° test events; there was a familiarity preference. In Condition B, which consisted of 12 instead of 7 180° familiarization trials, the 4‐month‐olds looked significantly longer at the 112° test events than the 180° test events; there was a novelty preference. In Condition C, which was similar to Condition A except that there were 112° familiarization trials, the infants showed a familiarity preference. Thus, 4‐month‐olds experiencing 7 familiarization trials exhibited a familiarity preference, and those experiencing 12 familiarization trials showed a novelty preference. In Condition D, 6‐month‐olds experienced 7 180° familiarization trials; there was no preferential looking to either familiar (180°) test events or novel (112°) test events. Therefore, looking behavior during the test trials was a function of the type of familiarization experience and age and not necessarily an inferred violation of physics.
Modeling Infant Speech Sound Discrimination Using Simple Associative Networks
Authors: Schafer Graham , Mareschal Denis
Published: January 2004

Infants' responses in speech sound discrimination tasks can be nonmonotonic over time. Stager and Werker (1997) reported such data in a bimodal habituation task. In this task, 8‐month‐old infants were capable of discriminations that involved minimal contrast pairs, whereas 14‐month‐old infants were not It was argued that the older infants' attenuated performance was linked to their processing of the stimuli for meaning. The authors suggested that these data are diagnostic of a qualitative shift in infant cognition. We describe an associative connectionist model showing a similar decrement in discrimination without any qualitative shift in processing. The model suggests that responses to phonemic contrasts may be a nonmonotonic function of experience with language. The implications of this idea are discussed. The model also provides a formal framework fer studying habituation‐dishabituation behaviors in infancy.
Evidence of Early Language Discrimination Abilities in Infants From Bilingual Environments
Authors: Bosch Laura , Sebastián‐Gallés Núria
Published: January 2004

Previous research data indicate that soon after birth, infants from monolingual families can discriminate utterances drawn from languages that differ prosodically, but discrimination between rhythmically similar languages, such as English and Dutch, has not yet been established by 2 months of age. In the case of bilinguals, the question of how early they can distinguish between the languages of exposure remains unanswered. The goal of this study was to analyze language discrimination capacities in 4‐month‐old bilingual infants simultaneously exposed to 2 Romance languages belonging to the same rhythmic category, Spanish and Catalan. Using a familiarization‐preference procedure, 2 groups of bilingual‐to‐be infants showed a capacity to discriminate between these 2 familial languages. Moreover, when compared with 2 groups of infants from monolingual environments, the size of the observed effects was the same. These results can be taken as initial evidence of an early capacity to distinguish languages in simultaneous bilingual exposure, thus challenging the hypothesis that language discrimination capacities are delayed in bilinguals.
Behavioral and Cortical Measures of Infants' Visual Expectations
Authors: Wentworth Naomi , Haith Marshall M. , Karrer Rathe
Published: January 2004

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.
Intersensory Redundancy and 7‐Month‐Old Infants' Memory for Arbitrary Syllable‐Object Relations
Authors: Gogate Lakshmi J. , Bahrick Lorraine E.
Published: January 2004

Seven‐month‐old infants require redundant information, such as temporal synchrony, to learn arbitrary syllable‐object relations (Gogate & Bahrick, 1998). Infants learned the relations between 2 spoken syllables, /a/ and /i/, and 2 moving objects only when temporal synchrony was present during habituation. This article presents 2 experiments to address infants' memory for these relations. In Experiment 1, infants remembered the syllable‐object relations after 10 min, only when temporal synchrony between the vocalizations and moving objects was provided during learning. In Experiment 2, 7‐month‐olds were habituated to the same syllable‐object pairs in the presence of temporal synchrony and tested for memory after 4 days. Once again, infants learned and showed emerging memory for the syllable‐object relations 4 days after original learning under the temporally synchronous condition. These findings are consistent with the view that prior to symbolic development, infants learn and remember word‐object relations by perceiving redundant information in the vocal and gestural communication of adults.
The Beginnings of Tool Use by Infants and Toddlers
Authors: McCarty Michael E. , Clifton Rachel K. , Collard Roberta R.
Published: January 2004

Children (aged 9, 14, 19, and 24 months) were encouraged to use tools to achieve a demonstrated goal. Each tool was most efficiently applied when held by the handle with the thumb toward the head of the tool in a radial grip. The tools were presented at midline and oriented to the left and right on alternating trials, so the children who managed to grasp a tool in both orientations with the radial grip demonstrated planning of actions in advance. The tools included a spoon, hairbrush, toy hammer, and magnet; the goals were to feed one's self, feed another, brush one's hair, brush another's hair, hit pegs, and retrieve metal objects. Children were found to use more radial grips with the self‐directed tools (i.e., hairbrush‐to‐self and spoon‐to‐self), indicating that they could plan their actions better when directed toward the self than toward an external goal.
Brain Electrical Activity Associated With Cognitive Processing During a Looking Version of the A‐Not‐B Task
Authors: Bell Martha Ann
Published: January 2004

This work was designed to investigate individual differences in brain electrical activity during a looking version of the A‐not‐B task. It was proposed that this spatial task required the cognitive skills of working memory and inhibitory control, each associated with frontal lobe function. Electroencephalograms (EEGs) were recorded from 54 8‐month‐old infants during baseline and task. Only high performers on the looking task exhibited increases in 6‐ to 9‐Hz EEG power from baseline to task. These task‐related changes were evident at frontal and posterior scalp locations. High performers on the looking task exhibited lower EEG coherence values at right hemisphere frontal locations relative to the low performers. These lower coherence values were evident during baseline and task. All infants showed increased frontal‐parietal coherence during the spatial working memory task relative to baseline values. These data confirm previous cognitive neuroscience work associating frontal lobe function with cognitive performance levels during infancy.
What Is Ecological Validity? A Dimensional Analysis
Authors: Schmuckler Mark A.
Published: January 2004

Ecological validityhas typically been taken to refer to whether or not one can generalize from observed behavior in the laboratory to natural behavior in the world. Although common in current discussions of research, the idea of ecological validity has a long history in psychological thought. A brief historical examination of this idea reveals that concerns with ecological validity are evident in multiple dimensions of experimental work, including the nature of the experimental setting, the stimuli under investigation, and the observer's response employed as the measure. One problem with this multidimensionality, however, is that no explicit criteria have been offered for applying this concept to an evaluation of research. One consequence of this problem is that concerns with ecological validity can be raised in most experimental situations. This article includes a discussion of some demands of ecological validity and the nature of these different dimensions, as well as a critical evaluation of research on the development of mobility with respect to these constraints.
The Salience of Multimodal Sensory Stimulation in Early Development: Implications for the Issue of Ecological Validity
Authors: Lickliter Robert , Bahrick Lorraine E.
Published: January 2004

Studies of infant development concerned with the emergence of specific perceptual or cognitive abilities have typically focused on responsiveness in only one sensory modality. Research on infant perception, learning, and memory often attempts to reduce multimodal stimulation to “noise” and to control or omit stimulation from other sensory modalities in experimental designs. This type of unimodal research, although important, may not generalize well to the behavior of infants in the multimodal context of the everyday world. Research from animal and human development is reviewed that documents that significant differences in infants' perceptual skills and abilities can be observed under conditions of unimodal versus multimodal stimulation. These studies provide converging evidence for a functional distinction between unimodal and multimodal stimulation during early development and suggest that ecological validity can be enhanced when research findings are generalized appropriately to the natural environment and are not overgeneralized across stimulus properties, tasks, or contexts.
Perceiving the Real World: Infants' Detection of and Memory for Social Information
Authors: Walker‐Andrews Arlene S. , Bahrick Lorraine E.
Published: January 2004

Research on infants' perception and memory for social information are discussed with respect to the concept of ecological validity. We argue that the use of dynamic, multimodal displays in familiar contexts is critical to understanding infants' developing perception. We also discuss the importance of generalizing appropriately from experimental to real‐world contexts and of using converging methods in the investigation of infants' capabilities.
Relations Between Women's Depressive Symptoms and Perceptions of Infant Distress Signals Varying in Pitch
Authors: Schuetze Pamela , Zeskind Philip Sanford
Published: January 2004

Fifteen nondepressed, 15 moderately depressed, and 15 severely depressed women rated tape‐recordings of a newborn infant's hunger cry digitally altered to increase in fundamental frequency in 100 Hz increments. Cries were rated on 4 perceptual (e.g., arousing‐not arousing) and 6 caregiving rating scale items (e.g., cuddle, feed) used in previous studies (Zeskind, 1983). Analyses of variance showed that, as cry pitch increased, cries were rated as more arousing, aversive, urgent, and sick sounding. Highest pitched cries received highest levels of caregiving interventions. Severely depressed women rated cries as less perceptually salient and less likely to elicit active caregiving responses. Interaction effects showed that severely depressed women were least responsive to highest pitched cries. These results suggest that women's depression may alter perceptions of infant distress signals, especially at times of greater infant distress.
Facial Expressivity at 4 Months: A Context by Expression Analysis
Authors: Bennett David S. , Bendersky Margaret , Lewis Michael
Published: January 2004

The specificity predicted by differential emotions theory (DET) for early facial expressions in response to 5 different eliciting situations was studied in a sample of 4‐month‐old infants (n = 150). Infants were videotaped during tickle, sour taste, jack‐in‐the‐box, arm restraint, and masked‐stranger situations and their expressions were coded second by second. Infants showed a variety of facial expressions in each situation; however, more infants exhibited positive (joy and surprise) than negative expressions (anger, disgust, fear, and sadness) across all situations except sour taste. Consistent with DET‐predicted specificity, joy expressions were the most common in response to tickling, and were less common in response to other situations. Surprise expressions were the most common in response to the jack‐in‐the‐box, as predicted, but also were the most common in response to the arm restraint and masked‐stranger situations, indicating a lack of specificity. No evidence of predicted specificity was found for anger, disgust, fear, and sadness expressions. Evidence of individual differences in expressivity within situations, as well as stability in the pattern across situations, underscores the need to examine both child and contextual factors in studying emotional development. The results provide little support for the DET postulate of situational specificity and suggest that a synthesis of differential emotions and dynamic systems theories of emotional expression should be considered.
The Effect of Excessive Crying on the Development of Emotion Regulation
Authors: Stifter Cynthia A. , Spinrad Tracy L.
Published: January 2004

The goal of this study was to examine the effect of excessive crying in early infancy on the development of emotion self‐regulation. Cry diaries were used to categorize excessive criers and typical criers at 6 weeks of age. At 5 and 10 months of age, infants and mothers participated in procedures to elicit infant reactivity and regulation during a frustration task and maternal sensitivity and intrusiveness during a free‐play session. Last, maternal ratings of temperament were obtained. Results revealed excessive criers to show higher levels of negative reactivity than typical criers. Excessive criers also demonstrated lower regulation, but this finding was only significant for male infants. Boys in the excessive criers group exhibited the lowest level of emotion self‐regulation. Maternal behavior and ratings of temperament at 5 and 10 months failed to distinguish the 2 cry groups. The findings suggest that excessive crying may influence the developmental trajectory of the ability of boys to self‐regulate emotion. The hypothesized processes involved in this outcome are discussed.
Infants' Behavioral Strategies for Emotion Regulation With Fathers and Mothers: Associations With Emotional Expressions and Attachment Quality
Authors: Diener Marissa L. , Mangelsdorf Sarah C. , McHale Jean L. , Frosch Cynthia A.
Published: January 2004

This study examined 12‐ and 13‐month‐old infants' behavioral strategies for emotion regulation, emotional expressions, regulatory styles, and attachment quality with fathers and mothers. Eighty‐five infants participated in the Strange Situation procedure to assess attachment quality with mothers and fathers. Infants' behavioral strategies for emotion regulation were examined with each parent during a competing demands task. Emotion regulation styles were meaningfully related to infant‐father attachment quality. Although expressions of distress and positive affect were not consistent across mothers and fathers, there was consistency in infant strategy use, emotion regulation style, and attachment quality with mothers and fathers. Furthermore, infants who were securely attached to both parents showed greater consistency in parent‐oriented strategies than infants who were insecurely attached to one or both parents. Limitations of this study include the constrained laboratory setting, potential carryover effects, and a homogeneous, middle‐class sample.
Frustration in Infancy: Implications for Emotion Regulation, Physiological Processes, and Temperament
Authors: Calkins Susan D. , Dedmon Susan E. , Gill Kathryn L. , Lomax Laura E. , Johnson Laura M.
Published: January 2004

A study sample of 162 six‐month‐old children was selected from a larger sample of 346 infants on the basis of parents' report of their infants' temperament and a laboratory assessment of temperament. Infants were classified as easily frustrated and less easily frustrated and compared on a number of emotion regulation, physiology, and temperament measures. Results indicated that male and female infants were equally likely to be classified as frustrated and less easily frustrated; however, male infants were less able to regulate physiologically. Easily frustrated infants used different emotion regulation strategies and were observed to be less attentive and more active than less easily frustrated infants when observed in the laboratory. These infants were also characterized by their parents as more active, less attentive, and more distressed to novelty. Infants classified as easily frustrated were more reactive physiologically and less able to regulate physiological reactivity than their less easily frustrated counterparts. It is hypothesized that this cluster of characteristics may constitute a unique temperamental type that may have implications for other types of behavioral functioning. Limitations of the study are that observations are based on a single brief assessment of the infant, modest effect sizes were found, and the study is cross‐sectional.
The Development of Maternal Self‐Efficacy and Its Impact on Maternal Behavior
Authors: Leerkes Esther M. , Crockenberg Susan C.
Published: January 2004

A developmental model of the origins of maternal self‐efficacy and its impact on maternal sensitivity was tested. Participants were 92 primiparous mothers and their 6‐month‐old infants. Mothers completed questionnaires about remembered care from their own parents and self‐esteem prenatally, satisfaction with support, infant temperament, and maternal self‐efficacy postnatally, and they participated in a laboratory observation with their infants. Maternal self‐efficacy was predicted by remembered maternal care as mediated by global self‐esteem. Infant soothability predicted maternal self‐efficacy independently and in conjunction with distress to novelty and in conjunction with both distress to limits and satisfaction with support. Maternal self‐efficacy interacted with distress to limits to predict maternal sensitivity during emotionally arousing activities. High infant distress was associated with less sensitive maternal behavior when maternal self‐efficacy was moderately low and extremely high, but was positively associated with sensitive maternal behavior when self‐efficacy was moderately high. Implications for future research are discussed.
Testing Infants' Discrimination With the Orientation Latency Procedure
Authors: Gout Ariel , Christophe Anne , Dupoux Emmanuel
Published: January 2004

A new discrimination procedure based on the measurement of visual orientation latency to speech stimuli is introduced. Each participant listens to a series of short familiarization test trials. In each trial, 5 to 7 centrally‐presented familiarization stimuli are followed by laterally‐presented test stimuli. Infants were found to orient faster to different‐category than to same‐category test stimuli. This result was found despite a high degree of prosodic variability in the familiarization and test stimuli introduced by changes in talker and speaking rate. The combination of a multitrial design with use of acoustic and prosodic variability seems suitable for studying the representation of phonological categories.
Spatiotemporal Regularity and Interevent Contingencies as Information for Infants' Visual Expectations
Authors: Wentworth Naomi , Haith Marshall M. , Hood Roberta
Published: January 2004

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.
Young Infants' Performance in the Object‐Variation Version of the Above‐Below Categorization Task: A Result of Perceptual Distraction or Conceptual Limitation?
Authors: Quinn Paul C. , Polly Jennifer L. , Furer Michael J. , Dobson Veima , Narter Dana B.
Published: January 2004

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.
The Effects of Alcohol in Breast Milk on Infant Behavioral State and Mother‐Infant Feeding Interactions
Authors: Schuetze Pamela , Eiden Rina Das , Chan Arthur W. K.
Published: January 2004

The short‐term impact of infant exposure to alcohol in breast milk on mother‐infant interactions and infant arousal was examined. Fourteen mother‐infant dyads were tested on 2 occasions that consisted of an alcohol administration and a nonalcohol condition. Mother‐infant interactions during feeding were videotaped and coded for dyadic reciprocity, maternal noncontingency, and dyadic conflict. Infants were observed for 1 hr after receiving either plain breast milk or breast milk containing alcohol. Behavioral state, startles, and tremors were recorded every 30 sec. Mother‐infant interactions were characterized by higher noncontingency and dyadic conflict in the alcohol condition. After drinking breast milk containing alcohol, infants changed behavioral state more often, startled more, and spent less time in quiet sleep and more time in quiet alert and crying states. These findings suggest that exposure to breast milk containing alcohol may not have a sedating effect, as commonly believed.
Jealousy in 6‐Month‐Old Infants
Authors: Hart Sybil , Carrington Heather
Published: January 2004

Thirty‐two 6‐month‐old infants were exposed to their mothers attending, in turn, to a lifelike baby doll and a book. Infant negativity was greater when maternal attention was directed toward the social object, suggesting the presence of an early form of jealousy by 6 months of age.
Speed of Processing and Face Recognition at 7 and 12 Months
Authors: Rose Susan A. , Jankowski Jeffery J. , Feldman Judith F.
Published: January 2004

This research examined developmental and individual differences in infants' speed of processing faces and the relation of processing speed to the type of information encoded. To gauge processing speed, 7‐ and 12‐month‐olds were repeatedly presented with the same face (frontal view), each time paired with a new one, until they showed a consistent preference for the new one. Subsequent probe trials assessed recognition of targets that either preserved configural integrity (Study 1: 3/4 profile and full profile poses) or disrupted it while preserving featural information (Study 2: rotations of 160° or 200° and fracturings). There were developmental differences in both speed and in infants' appreciation of information about faces. Older infants took about 60% fewer trials to reach criterion and had more mature patterns of attention (i.e., looks of shorter duration and more shifts of gaze). Whereas infants of both ages recognized the familiar face in a 3/4 pose, the 12‐month‐olds also recognized it in profile and when rotated. Twelve‐month‐olds who were fast processors additionally recognized the fractured faces; otherwise, processing speed was unrelated to the type of information extracted. At 7 months then, infants made use of some configural information in processing faces; at 12 months, they made use of even more of the configural information, along with part‐based or featural information.
Infants' Use of Constraints to Speed Information Processing and to Anticipate Events
Authors: Dougherty Thomas M. , Haith Marshall M.
Published: January 2004

Two experiments were conducted with 28‐week‐old infants using a modification of the Visual Expectation Paradigm. The first sought to determine whether speed of information processing (SIP) could be assessed in infants using a reaction time (RT) measure and approach that is widely used to measure SIP in adults. Infants saw a center fixation cue followed by a peripheral target that could appear in 1, 2, or 4 locations. There was a linear increase in RT of eye movements as the number of locations increased from 1 to 2 and to 4 targets, suggesting that the paradigm does measure SIP. The second experiment asked whether varying the number of cue‐target pairings would augment or impair infant's SIP in the trade‐off between the benefit of additional information and the liability of additional memory load. The findings showed that the presence of cue information can eliminate the difference in RT between the 1‐ and 2‐location conditions, whereas no benefit of cue was obtained for the 4‐location condition.
The Development of Anticipatory Postural Adjustments in Infancy
Authors: Witherington David C. , von Hofsten Claes , Rosander Kerstin , Robinette Amanda , Woollacott Marjorie H. , Bertenthal Bennett I.
Published: January 2004

Efficient voluntary action requires postural adjustments that compensate for potential balance disturbances before they occur. These anticipatory postural adjustments have been widely investigated in adults, but relatively little is known about their development, especially during infancy. This study examined the early development of anticipatory postural activity in support of pulling action while standing. A total of 34 infants between 10 and 17 months were tested. The task required infants to open a cabinet drawer to retrieve toys while a force resisting the pulling action was applied to the drawer. The experiment included between 9 and 13 pulling trials. The force resisting the pull was doubled after the first 4 initial trials and returned again to its original value after another 4 trials. Electromyographic activity from the gastrocnemius and biceps brachii muscles was recorded. The proportion of pulls involving anticipatory activity in the gastrocnemius muscles progressively increased between 10 and 17 months. In addition, infants with considerable experience in opening drawers learned to recruit greater strength of their anticipatory postural adjustments for heavier pulls. Implications for the role of motoric experience in anticipatory postural activity are discussed.
The Effect of the Number of A Trials on Performance on the A‐Not‐B Task
Authors: Marcovitch Stuart , Zelazo Philip David , Schmuckler Mark A.
Published: January 2004

The A‐not‐B error (Piaget, 1954), which occurs when infants search perseveratively on reversal trials in a delayed‐response task, is one of the most widely studied phenomena in developmental psychology. Nonetheless, the effect of A‐trial experience on the probability and magnitude of this error remains unclear. In this study, 9‐month‐old infants were tested at location A until they searched correctly on 1, 6, or 11 A trials. Results revealed an effect of A trials on the proportion of infants who erred on the first B trial, and on the number of errors prior to a correct search at B (i.e., the error run). These effects were asymptotic, or U‐shaped, consistent with a dual‐process model according to which A‐trial experience increases habit strength but also provides opportunities for reflection on task structure.
Infants' Responses to Gender‐Inconsistent Events
Authors: Serbin Lisa A. , Poulin‐Dubois Diane , Eichstedt Julie A.
Published: January 2004

Toddlers' knowledge of the stereotyping of traditionally feminine and masculine household activities was examined using the preferential looking paradigm. Seventy‐seven 24‐month‐old infants observed a series of 9 pairs of photographs, each portraying a male and female adult engaged in the same stereotyped or gender‐neutral activity (e.g., ironing, hammering, or reading). Longer looking times were predicted on stimuli inconsistent with gender stereotypes (e.g., looking longer at the man putting on lipstick than at the woman). The results suggested that toddlers have acquired some knowledge of the gender stereotyping of feminine activities by their 2nd birthday.
Relations Between Measures of Irritability and Contingency Detection at 6 Months
Authors: Lemelin Jean‐Pascal , Tarabulsy George M. , Provost Marc A.
Published: January 2004

The hypothesis that irritability and contingency detection are negatively correlated was examined in thirty‐one 6‐month‐old infants. Observation and maternal report‐based assessments of irritability were correlated with both a criterion score and a continuous score of contingency detection. Results indicated that greater irritability in infants was associated with lower contingency detection scores. Discussion focuses on identifying processes by which the 2 constructs may be associated.
Peripheral Stimulus Localization by 5‐ to 14‐Week‐Old Infants During Phases of Attention
Authors: Hunter Sharon K. , Richards John E.
Published: January 2004

This study examined the effect of attention in young infants on the saccadic localization of peripheral stimuli. Infants ranging in age from 5 to 14 weeks were tested using a peripheral stimulus detection paradigm. The presence of a central fixation stimulus decreased detection probability, particularly if attention was engaged with the central stimulus. Peripheral stimulus localization usually was accomplished with a single eye movement. When localization was accomplished by multiple eye movements, corrective saccades occurred most frequently and fixed‐amplitude hypometric saccades occurred less frequently. A decrease in the slope of the linear component of the main sequence was found from 5 to 11 weeks of age, and this decrease was independent of attention.
Sensitivity to Social Contingency From Mothers and Strangers in 2‐, 4‐, and 6‐Month‐Old Infants
Authors: Bigelow Ann E. , DeCoste Cindy
Published: January 2004

Infants' sensitivity to changes in social contingency was investigated by presenting 2‐, 4‐, and 6‐month‐old infants with 3 episodes of social interaction from mothers and strangers: 2 contingent interactions and 1 noncontingent replay. Three orders were presented: (a) contingent, noncontingent, contingent; (b) contingent, contingent, noncontingent; and (c) noncontingent, contingent, contingent. Contingency and carryover effects were shown to both mothers and strangers in the different orders of presentation. Infants were more visually attentive to contingent interactions than to the noncontingent replay when contingent interactions occurred prior to the replay, and the infants' level of attention to the noncontingent replay carried over to subsequent contingent interactions. The 4‐ and 6‐month‐old infants showed contingency and carryover effects by their visual attention and smiling. Examination of effect sizes for attention suggests 2‐month‐old infants may be beginning to show the effects. Reasons for age changes in sensitivity to social contingency are discussed.
Rhythm in Mother‐Infant Interactions
Authors: Deckner Deborah F. , Adamson Lauren B. , Bakeman Roger
Published: January 2004

Rhythmic behavior and the association of vocal rhythmic behavior with language development were studied in a sample of 30 mother‐infant dyads. Dyads were observed in 2 contexts (1 involved sharing pictures and the other sharing musical toys) when infants were 18 and 24 months of age. Vocal rhythmic behavior was seen in both contexts, and in both contexts mothers matched their infant's vocal rhythmic behavior at greater than chance rates. Greater matching tended to be associated with higher language scores whereas, counter to prediction, higher rates of maternal vocal rhythmic behavior tended to be associated with lower language scores. At 24 months of age, mother‐daughter dyads showed more matching than mother‐son dyads. These results suggest that differences in maternal production of vocal rhythmic behavior may foster different language learning strategies.
Agreement Between Mothers and Fathers on the Identification of Infant Communicative Acts: Use of a Randomization Procedure
Authors: Elias Gordon , Meadows Denis , Bain John D.
Published: January 2004

The extent to which mothers and fathers agree on what they identify as their infant's communicative acts was investigated. Nineteen infants (6 at 6 months, 7 at 9 months, and 6 at 12 months) and their parents participated. A randomization procedure controlled for the frequencies and durations of the communicative acts identified by the parents, and the procedure produced a distribution of 10,000 “chance” agreement values for each parent pair with which their observed level of agreement was compared. The results indicated that, generally, parents could identify their infant's communicative acts consistently, and that observed levels of agreement between parents were significantly higher than would be expected by chance. Differences between mothers and fathers on their identification of communicative acts are considered in terms of the emergence of the infant's intention to communicate.
Young Infants' Perception of Object Unity in Rotation Displays
Authors: Johnson Scott P. , Cohen Leslie B. , Marks Kathryn H. , Johnson Kerri L.
Published: January 2004

Much research has been devoted to questions regarding how infants begin to perceive the unity of partly occluded objects, and it is clear that object motion plays a central role. Little is known, however, about how infants' motion processing skills are used in such tasks. One important kinetic cue for object shape is structure from motion, but its role in unity perception remains unknown. To address this issue, we presented 2‐ and 4‐month‐old infants with displays in which object unity was specified by vertical rotation. After habituation to this display, infants viewed broken and complete versions of the object to test their preference for the broken object, an indication of perception of unity in the occlusion display. Positive evidence for the perception of unity was provided by both age groups. Concomitant edge translation available in 1 condition did not appear to contribute above and beyond simple rotation. These results suggest that structure from motion, and perhaps contour deformation and shading cues, can contribute important information for veridical object percepts in very young infants.
A Comparison of Visual Familiarization and Object‐Examining Measures of Categorization in 9‐Month‐Old Infants
Authors: Younger Barbara A. , Furrer Stephanie D.
Published: January 2004

Three studies were conducted to determine whether differential patterns of categorization observed in studies using visual familiarization and object‐examining measures hold up as procedural confounds are eliminated. In Experiment 1, we attempted as direct a comparison as possible between visual and object‐examining measures of categorization. Consistent with previous reports, 9‐month‐old infants distinguished a basic‐level contrast (dog–horse) in the visual task, but not in the examining task. Experiment 2 was designed to reduce levels of nonexploratory activity in an examining task; 9‐month‐olds again failed to distinguish categories of dogs and horses. In Experiment 3, we adopted a paired‐comparison test format in the object‐examining task. Infants did display a novel category preference under paired testing conditions. The results suggest that the different patterns of categorization often seen in looking and touching tasks are a reflection, not of different categorization processes, but of the differential sensitivity of the tasks.
Visual Access and Attention in Two‐Year‐Olds' Event Reasoning and Object Search
Authors: Mash Clay , Keen Rachel , Berthier Neil E.
Published: January 2004

Several recent studies have revealed substantial limitations in 2‐year‐olds' ability to search accurately for objects that have undergone unseen movement, even along highly constrained paths. In many of these studies, children observed a ball as it rolled down a track and behind an occluding panel that contained 4 doors. The track had a barrier that was partly visible and could be placed in locations corresponding to the doors. When the ball came to a rest against the barrier and behind the occluder, the child's task was to find the ball by opening the correct door. The search accuracy of 2‐year‐olds has not differed from chance across several variations of this task. This research was conducted to identify the source of 2‐year‐olds' limitation in this domain. Children were granted a full view of the event before the ball was occluded with a door panel. Children's performance was better under this condition, but was still not systematically accurate unless their gaze remained locked onto the correct location. Two‐year‐olds' weak performance in these search tasks appears to be more a consequence of limitations in spatial integration than in their representation of unseen movement.
The Nature of Infants' Visual Expectations for Event Content
Authors: Adler Scott A. , Haith Marshall M.
Published: January 2004

Recent studies have revealed that young infants can form expectations for the spatial location of future visual events. Four experiments examined whether 3‐month‐old infants also form expectations for content features of events, defined as an invariant color combination. Infants viewed a spatially alternating (left–right) sequence of varying pictures in which pictures on one side (invariant colors) always appeared with the same color combination (e.g., red/green), while on the other side (varied colors) the pictures appeared with any of 4 possible color combinations. Results indicated that infants formed a content expectation for the invariant color combination on the invariant side, such that their anticipatory responding was disrupted by a novel color combination event and by a novel pattern event. A dissociation between reactive and anticipatory eye movements in their sensitivity to the content manipulation suggests that infants' expectations for spatial and content information engage somewhat different processes.
Electrophysiological Brain Responses of Six‐Month‐Old Low Risk Premature Infants
Authors: Stolarova Margarita , Whitney Heather , Webb Sara J. , de Regnier Raye‐Ann , Georgieff Michael K. , Nelson Charles A.
Published: January 2004

This study sought to examine the electrophysiological correlates of visual perceptual priming in a sample of low risk preterm infants. We compared the ERP data of 20 healthy preterm infants at the age of 6 months (corrected age: 4 months) to those of 20 six‐month‐old and 20 four‐month‐old full term infants. The comparison groups represented the preterm infants' chronological and corrected ages respectively. The results showed that the brain responses of the preterm infants at the age of 6 months, specifically the topography and the latency of the Nc component, are more similar to those of their corrected age peers than to those of the chronological age controls.
The Still Face: A History of a Shared Experimental Paradigm
Authors: Adamson Lauren B. , Frick Janet E.
Published: January 2004

When faced by a suddenly unresponsive social partner, young infants typically react by sobering and gazing away. This still‐face reaction has intrigued researchers for several decades. In this article, we present a history of the still‐face paradigm in which we locate early observations of the still‐face effect, describe the formalization of a procedure that reliably produces it, and discuss how this procedure has been used to investigate a broad range of questions about early social and emotional development. In addition, we reflect on the heuristic value of shared experimental paradigms.