Abstract: Studies on adults have demonstrated that the perception our own body can be manipulated by varying both temporal and spatial properties of multisensory information. While human newborns are capable of detecting the temporal synchrony of visuo-tactile body-related cues, it remains unknown whether they also utilise spatial information for body perception. Twenty newborns were presented with a video of an infant's face touched with a paintbrush, while their own face was touched either in the spatially congruent, or an incongruent, location. We found that newborns show a visual preference for spatially congruent synchronous events, supporting the view that newborns have a rudimentary sense of their own body.

Abstract: © 2015 The International Society on Infant Studies 20 3 May-June 2015 10.1111/infa.12071 Research Article RESEARCH ARTICLES Copyright © International Society on Infant Studies (ISIS). The acquisition of walking has recently been linked with infant language development (Walle & Campos, 2014). If this relation reflects the consequence of an epigenetic event, then it should be present regardless of when the infant typically begins to walk, the infant's culture, and the infant's native language. This study sought to replicate the previously reported link between walking and language development in American infants and investigate whether this relation exists cross-nationally in typically developing Chinese infants exposed to Mandarin. Urban Chinese infants not only provide a distinct linguistic and cultural population in which to study this relation but also typically begin walking approximately 6 weeks later than American infants. Our results demonstrated that (1) walking infants in both the American and Chinese samples had greater receptive and productive vocabularies than same-aged crawling infants, (2) differences between crawling and walking infants were proportionally similar in each sample, and (3) the walking-language relation was present for both noun and non-noun vocabularies. These findings provide further support of a relation between infant walking onset and language development, independent of age. Avenues for future research of the processes involved in this relation, as well as additional populations of interest to investigate, are discussed. Copyright

Abstract: The ability to effectively regulate emotions is an important marker for early socioemotional development. The uses of self-comforting behaviors and self-distraction have been empirically supported as effective regulatory strategies for infants, though research on determinants of such behaviors is scarce. Thus, a more thorough examination of the development of regulatory behaviors is needed. For the current study, 135 mothers, fathers, and their infants participated in laboratory visits at 3-, 5-, and 7-months of age where parent sensitivity and infant regulatory strategies were coded from the Still Face Paradigm. Parents also filled out questionnaires about infant temperament and parental involvement. Using multi-level modeling to examine levels and trajectories of self-comforting and self-distraction, the current study found: 1) infants higher in temperamental surgency used more self-distraction and self-comforting, 2) infants lower in surgency with highly involved parents increased in self-distraction at a faster rate, particularly with highly involved fathers, and 3) infants used self-comforting more than average with fathers when the infant was also lower in temperamental regulation. In addition, we examined trajectories of parent involvement and temperament in relation to infant regulatory strategy.

Abstract: Fearful and self-conscious subtypes of shyness have received little attention in the empirical literature. Study aims included: 1) determining if fearful shyness predicted self-conscious shyness, 2) describing development of self-conscious shyness, and 3) examining genetic and environmental contributions to fearful and self-conscious shyness. Observed self-conscious shyness was examined at 19, 22, 25, and 28 months in same-sex twins (MZ = 102, DZ = 111, missing zygosity = 3 pairs). Self-conscious shyness increased across toddlerhood, but onset was earlier than predicted by theory. Fearful shyness (observed [6 and 12 months] and parents' reports [12 and 22 months]) was not predictive of self-conscious shyness. Independent genetic factors made strong contributions to parent-reported (but not observed) fearful shyness (additive genetic influence = .69 and .72 at 12 and 22 months, respectively) and self-conscious shyness (additive genetic influence = .90 for the growth model intercept). Results encourage future investigation of patterns of change and interrelations in shyness subtypes.

Abstract: Structural cues, such as the relative size and arrangement of parts, are key aspects of adults' representation of human bodies, and they are used to derive significant social information such as age, sex, and attractiveness. Prior studies have not clearly addressed young infants' sensitivity to these body characteristics. In the current experiments, 3.5-month-olds exhibited a preference between images of intact bodies versus those with parts in wrong locations. Infants also discriminated between intact bodies and those with distorted part proportions. In both cases, infants discriminated when images were presented upright but not when they were inverted. These results indicate that infants are sensitive to the arrangement and size of human body parts at least by 3.5 months of age. Thus, contrary to some prior reports, body representation early in life is developed enough to include structural information.

Abstract: Caregiver education is known to relate to the growth of children, but possible mediation mechanisms of this association are poorly characterized and generally lack empirical support. We test whether instructional capital (caregiver education) leads to improved infant growth through availability of physical capital (household resources) across a wide swath of low- and middle-income countries (LMIC). Using the Multiple Indicator Cluster Survey (MICS3), we explore relations among caregiver education, household resources, and infant (M age = .99 years) growth in 117,881 families living in 39 LMIC. Overall, household resources mediated 76% of the small association between caregiver education and infant growth. When disaggregated by countries characterized by low, medium, and high levels of human development (as indexed by average life expectancy, education, and gross domestic product), household resources mediated 48% to 78% of the association between caregiver education and infant growth. Caregiver education had effects on infant growth through household resources in countries characterized by low, medium, and high levels of human development; for girls and boys; and controlling for indexes of infant feeding and health.

Abstract: Early developments in toddlers’ responses to adults’ distress have been extensively examined, but less work has been directed to young children’s responses to other children in distress. In the current study, we examined 12-, 18-, and 24-month-old children’s (N = 71) behavioral and affective responses to a crying infant (doll) present in the room with the child. A comparison condition included a contented, neutral infant to contrast with the crying infant so as to disambiguate social interest from distress-specific responding. Results showed that 12-month-olds were neither particularly interested in nor concerned about the infant, although they did discriminate between conditions. In contrast, 18- and 24-month-olds were socially interested and attentive to the infant, but 24-month-olds exhibited greater affective concern to the crying infant than did 18-month-olds. Children at all three ages were also mildly distressed themselves by the infant’s crying, and this did not decline over the second year. Both girls and children without

Abstract: One of the most salient social categories conveyed by human faces and voices is gender. We investigated the developmental emergence of the ability to perceive the coherence of auditory and visual attributes of gender in 6- and 9-month-old infants. Infants viewed two side-by-side video clips of a man and a woman singing a nursery rhyme and heard a synchronous male or female soundtrack. Results showed that 6-month-old infants did not match the audible and visible attributes of gender, and 9-month-old infants matched only female faces and voices. These findings indicate that the ability to perceive the multisensory coherence of gender emerges relatively late in infancy and that it reflects the greater experience that most infants have with female faces and voices.

Abstract: Maternal mind-mindedness, which is a measure of maternal mentalization involving mothers' speech, was examined as a predictor of mothers' mirroring of infant behavior during interaction. Five-month-old infants and their mothers engaged in a Still-Face Task in which the mother's mirroring of the infant's behavior was assessed. After the task, the mother was shown a video of her infant in the task and asked to comment on what was happening for her infant; her comments were assessed for mind-mindedness. Maternal mind-mindedness when mothers were asked to reflect upon what was happening for their infants during the task predicted mothers' mirroring behaviors while engaged with their infants in the task. Maternal mirroring behavior may be a manifestation of maternal mentalization that is salient to infants.

Abstract: In this study, we examined the effects of infant country and exemplar material on 24 US and 22 Malawian (African) 15-month-olds' categorization of animals versus vehicles. Following familiarization with either plastic or wooden animal replicas, infants were tested with objects of both materials in a standard object-examining task. Both US and Malawian infants demonstrated category formation regardless of the material of the animal replicas. In addition, infants extended a category of plastic animals to novel wooden animals, but did not extend a category of wooden animals to novel plastic animals. These findings document a uniform impact of stimuli characteristics on infant object categorization despite differences in infant cultural background and toy animal experience. In addition, they show that, in some cases, infants can generalize their categorization of animals from one type of replica to another.

Abstract: Gaze is one of the main means of communication in young infants, and it has been shown to be important for subsequent socio-emotional and cognitive development. Maternal depression is a well-known risk factor for disrupting mother–infant interactions, but findings regarding gaze behavior in infants of depressed versus nondepressed mothers have been ambiguous. In this study, we examined gaze duration and activity in a sample of 27 infants of mothers with postpartum depression (PPD) and 49 infants of nondepressed mothers. Maternal depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale, and diagnoses were confirmed in clinical interview. Infant gaze was assessed during 4-month face-to-face interactions using continuous timed-event coding with high temporal resolution. Although we found no differences in gaze duration, infants of PPD mothers had both significantly less Gaze On and also less Gaze Off events. Findings suggest that PPD is related to reduced gaze activity during mother–infant interaction in 4-month-olds. This reduced activity may have long-term negative consequences for child development.

Abstract: Early childhood behavior problems may indicate risk for subsequent psychopathology (Shaw, Gilliom, Ingoldsby, & Nagin, Developmental Psychology, 39, 2003, 189). There is some evidence to suggest that boys and girls may be differentially susceptible to postpartum risk factors that predict problem behaviors in early childhood (Kochanska, Coy, & Murray, Child Development, 72, 2001, 1091; Martel, Klump, Nigg, Breedlove, & Sisk, Hormones and Behavior , 55, 2009, 465). The main aim of this study is to examine whether child sex moderates the effect of infant and maternal predictors of toddler problem behaviors in a unique sample of high-risk mother–child dyads. Analyses were based on data collected for 198 mother–child dyads (52% male offspring) followed longitudinally from birth to 18 months. Maternal and infant variables, including maternal PTSD and depression symptoms, maternal maltreatment history, observed maternal parenting quality, demographic risk, and infant negative emotionality and night waking, were used to predict toddler behavior problems. Although boys and girls displayed similar levels of total problem behaviors at 18 months overall, the specific set of infant and maternal variables that predicted toddler problems varied by child sex. The significant predictor for boys was maternal PTSD symptoms, whereas significant predictors for girls were infant negative emotionality and sleep problems. Results suggest that sex-differentiated transmission of risk can be identified as early as 18 months postpartum. These differences suggest a gender-specific biological sensitivity to maternal psychopathology, or alternatively, a gender-specific reporting bias among mothers with childhood maltreatment histories.

Abstract: We demonstrate that 18-month-olds, but not 14-month-olds, can anticipate others' actions based on an interpretation of shared goals that bind together individual actions into a collaborative sequence. After viewing a sequence of actions performed by two people who socially interact, 18-month-olds bound together the socially engaged actors' actions such that they later expected the actors to share the same final goal. Eighteen-month-olds who saw nonsocially engaged actors did not have this expectation and neither did 14-month-olds when viewing either socially or nonsocially engaged actors. The results are discussed in light of the possibility that experience in collaborations could be necessary for understanding collaboration from a third-person perspective.

Abstract: Sensitivity to language-specific stress patterns during infancy facilitates find-ing, mapping, and recognizing words, and early preferences for the predomi-nate stress pattern of the infant’s native language have been argued tofacilitate language relevant outcomes (Ference & Curtin, 2013 Journal ofExperimental Child Psychology, 116, 891; Weber et al., 2005 Cognitive BrainResearch, 25, 180). We examined 12-month-old infant siblings of typicallydeveloping children (SIBS-TD) and infant siblings of children diagnosedwith autism spectrum disorder (ASD; SIBS-A) on their ability to map differ-entially stressed labels to objects. We also examined whether success at thistask relates to infants’ vocabulary size at 12 months, and more specificallyto SIBS-A’s vocabulary at both 12 and 24 months. SIBS-TD successfullymapped the word–object pairings, which related to their vocabulary compre-hension at 12 months. In contrast, SIBS-A as a group did not map theword–object pairings, which was unrelated to vocabulary size at 12 months.However, success on this task for SIBS-A predicted expressive language abil-ities at 24 months using the Mullen Scales of Early Learning (MSEL; Mul-len, 1995 Mullen Scales of Early Learning. Circle Pines, MN: AmericanGuidance) and the MacArthur-Bates Communicative Development Inven-tory (MB-CDI; Fenson et al., 1993 MacArthur Communicative Development

Abstract: Research has demonstrated that intersensory redundancy (stimulation synchronized across multiple senses) is highly salient and facilitates processing of amodal properties in multimodal events, bootstrapping early perceptual development. The present study is the first to extend this central principle of the intersensory redundancy hypothesis (IRH) to certain types of intrasensory redundancy (stimulation synchronized within a single sense). Infants were habituated to videos of a toy hammer tapping silently (unimodal control), depicting intersensory redundancy (synchronized with a soundtrack) or intrasensory redundancy (synchronized with another visual event; light flashing or bat tapping). In Experiment 1, 2-month-olds showed both intersensory and intrasensory facilitation (with respect to the unimodal control) for detecting a change in tempo. However, intrasensory facilitation was found when the hammer was synchronized with the light flashing (different motion) but not with the bat tapping (same motion). Experiment 2 tested 3-month-olds using a somewhat easier tempo contrast. Results supported a similarity hypothesis: intrasensory redundancy between two dissimilar events was more effective than that between two similar events for promoting processing of amodal properties. These findings extend the IRH and indicate that in addition to intersensory redundancy, intrasensory redundancy between two synchronized dissimilar visual events is also effective in promoting perceptual processing of amodal event properties.

Abstract: Several years ago, the American Psychological Association began requiring that effect size estimates be reported to provide a better indication of the associative strength between factors and dependent measures in empirical studies (Publication manual of the American Psychological Association, 2010, Author, Washington, DC). Accordingly, developmental journals require/strongly recommend effect size estimates be included in published work. Potentially, this trend has important benefits for infancy research given some of the inherent difficulties in establishing conceptually strong findings when often facing highly variable performance in typically small samples. This study examined recent infant research from select journals for accuracy and interpretative value of effect size estimates. Demographics, sample size, design, and statistical data were coded from 158 published (2007–2012) articles presenting 878 effect size estimates from experimental findings with infants using behavioral methods. Descriptive and distribution statistics were calculated for the following variables: (1) statistical tests, (2) effect size parameters, and (3) effect size interpretations. Although partial eta squared () and eta squared (η2) were most common (49 and 42%, respectively), “η confusion” was apparent, and interpretation of effect size estimates was virtually nonexistent. Thus, effect size estimates are not impacting infant development research in spite of criticisms of sole dependence on null hypothesis (e.g. American Psychologist, 49, 1994 and 997). Suggestions for increasing accuracy of effect size estimate selection and interpretative effect size estimate cutoffs are offered to improve empirical clarity.

Abstract: We investigated whether crawling versus noncrawling infants interpret an agent's movements around an obstacle as goal-directed. Infants (6–9 months) were habituated to a self-propelled circle jumping over an obstacle to reach a goal. When the obstacle was removed, infants who crawled (n = 13) showed longer looking time to the familiar but now nonrational jumping path versus a novel but rational straight-line path. Noncrawlers (n = 17) did not discriminate. Looking preference was independent of age and speed of habituation. These findings support the claim that infants’ processing of agency emerges early and applies to all agents, but stress the role of experience in the development of action interpretation.

Abstract: The ability of infants to recognize phonotactic patterns in their native language is widely acknowledged. However, the specific ability of infants to recognize patterns created by nonadjacent vowels in words has seldom been investigated. In Semitic languages such as Hebrew, groups of multisyllabic words are identical in their nonadjacent vowel sequences and stress position but differ in the consonants interposed between the vowels. The goals of this study were to assess whether infants learning Hebrew show a preference for (1) a nonadjacent vocalic pattern or template, common in Hebrew nouns (CeCeC), over a nonattested nonadjacent vocalic pattern (CoCoC), and (2) a nonadjacent vocalic pattern common in Hebrew words (CaCoC) over an existing but less common pattern (CaCeC). Twenty Hebrew-learning infants aged 8 to 11 months were presented with lists of nonsense words featuring the first two patterns (Experiment 1), and 20 were presented with nonsense words featuring the second two patterns (Experiment 2). The results showed longer listening to CeCeC than to CoCoC lists and to CaCoC than to CaCeC lists, suggesting that infants recognized the common nonadjacent vocalic patterns in both cases. The study thus demonstrates that Hebrew-learning infants are able to disregard the intervening consonants within words and generalize their vocalic pattern to previously unheard nonwords, whether this pattern includes identical or different vowels and regardless of the rhythmic pattern of the word (trochaic or iambic). Analysis of the occurrence of the relevant vowel patterns in input speech in three Hebrew corpora (two addressed to children and one to adults) suggests that exposure to these patterns in words underlies the infants' preferences.

Abstract: Despite the developmental and clinical relevance of this area of inquiry, no studies have examined the interrelations of trait vulnerabilities in the affective, behavioral, and interpersonal domains between mothers and their infants Thus, this study examined the interrelations of three trait vulnerabilities (ie, negative affective intensity, impulsivity, and insecure attachment) between mothers and their 12- to 23-month-old infants, focusing in particular on the unique and interactive influence of these maternal trait vulnerabilities on the expression of and precursors to these traits in their infants Mother–infant dyads (N = 101) completed several laboratory procedures, and mothers reported on their own and their infants' expressions of the trait vulnerabilities of interest Findings from this study provide preliminary evidence for intergenerational relations between these traits and suggest that it is the confluence of trait vulnerabilities in mothers that relates to the early expression of some of these traits in infants

Abstract: 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.

Abstract: The assessment of the quality of infants’ spontaneous movements is a diagnostic tool for the young nervous system. We examined whether it relates to the quality of the interactions between infants born preterm and their mothers. Thirty-nine healthy infants born preterm (Mage in weeks = 14.59, SD = 2.21; 38.46% female) and their mothers participated in the study. Infants’ quality of spontaneous movements was assessed using the General Movement Assessment according to Prechtl (Prechtl, Early Human Development 1990, 23, 151). A new measurement was employed to evaluate the following aspects of the mother–infant interaction: maternal sensitivity in the motor modality (i.e., when touching, picking up, holding, and putting down the infant), maternal sensitivity in the modalities of vocalization and eye contact, and infants’ positive engagement. Several aspects of infants’ quality of movements were associated with maternal sensitivity in the motor modality and infants’ positive engagement, but not with maternal sensitivity in the modalities of vocalization and eye contact. These findings suggest that the quality of infants’ spontaneous movements may explain some of the variability in the interactions between infants born preterm and their mothers. The results also highlight the importance of differentiating between the modalities of mothers’ behavior when assessing their sensitivity. Implications for research and practice with families of preterm infants are discussed.

Abstract: This paper examines the predictive relations between two infant temperamental biases assessed at 4 months and inhibited behavior during the first two years of life in three independent samples from two research laboratories. Although each sample used slightly different criteria for classifying infants, the results across samples were consistent. Infants of both genders who displayed high levels of motor activity and distress to unfamiliar events were more inhibited at 14 months of age. By 24 months there were significant sex differences: boys identified as high reactive were more inhibited than high reactive girls.

Abstract: In my presidential address, I described the early trap I fell into of describing the super-baby capable of one after another adult perceptual ability, then how I discovered that two atypical populations of adults allowed me to study developmental mechanisms, namely, the role of early sensory input in sculpting the nervous system and the biological preparedness that constrains the experiential effects. Specifically, studies of adults who had dense central cataracts during childhood revealed that there are multiple critical periods during which visual input alters the potential of the nervous system for later refinement. Studies of adults with synesthesia generated novel hypotheses, subsequently supported experimentally, about the details of the biological preparedness that bias the child's early learning. Nevertheless, later studies indicated that considerable residual plasticity remains in adulthood.

Abstract: While a large literature discusses young infants' preference for an infant-directed speaking style, few studies have explored preferences after the first year. The present work compares infants' preference for two different properties of IDS speech: prosodic changes (primarily pitch and pitch variability) and structural properties (utterance length; lexical repetition). We found that both 12- and 16-month-old infants continued to prefer listening to speech with the prosodic properties of IDS, but neither age showed any preference for speech with the lexical repetition and short utterances typical of IDS.

Abstract: To successfully understand spoken language, listeners need to determine how words within sentences relate to one another. Although the ability to compute relationships between word categories is known to develop early in life, little research has been conducted on infants' early sensitivity to subcategorical dependencies, such as those evoked by grammatical gender (where the article form is dictated by the noun's gender). This study therefore examines whether French-learning 18-month-olds track such relationships. Using the Visual Fixation Procedure, infants were presented with article–noun sequences in which the gender-marked article either matched (e.g., laFEM poussetteFEM “the stroller”) or mismatched (e.g., leMASC poussetteFEM) the gender of the noun. A clear preference for correct over incorrect co-occurrences was observed, suggesting that by 18 months of age, children's storage and access of words is sufficiently sophisticated to include the means to track subcategorical dependencies. This early sensitivity to gender information may be greatly beneficial for constraining lexical access during online language processing.

Abstract: Small-scale eye-tracking research lends support to behavioral studies of relational memory by 6 months of life. Here, in the largest eye-tracking test of relational memory to date (n = 276), we replicate these findings and examine the impact of excluding data based on looking behavior characteristics at test. Past work examining infants' preferential looking toward arbitrary-paired objects and scenes has excluded infants from analysis based upon “insufficient looking” at test. Yet, research suggests that variation in looking behavior may be associated with looking patterns during encoding, as well as trait-like differences in visual and cognitive processing. Similar to past research, we observed evidence for relational memory among 6-month-olds. In keeping with past research, when infants were excluded based on “insufficient looking,” we observed evidence for relational memory only when infants were tested immediately. However, when exclusion criteria were relaxed, infants specifically demonstrated preferential looking during a presumably more difficult delay-plus-interference condition. Moreover, analyses revealed that looking behavior during encoding was associated with looking behavior at test. Together, results suggest that infants do possess rudimentary relational memory capabilities, but that experimenters' ability to detect these capabilities is influenced by both experimental conditions and individual differences in looking behavior.

Abstract: We provide an analysis of hold out and giving (Ho&G) behaviours in pre-linguistic infants, and investigate their relationship with index finger pointing. The frequency of Ho&Gs at 10 and 11 months along with the length of the following social interaction correlated with index finger pointing at 12 months. We conclude that Ho&Gs are a precursor to index finger pointing and that this provides support for social-pragmatic approaches to communicative development.

Abstract: Across three experiments, we examined 9- and 11-month-olds' mappings of novel sound properties to novel animal categories. Infants were familiarized with novel animal–novel sound pairings (e.g., Animal A [red]–Sound 1) and then tested on: (1) their acquisition of the original pairing and (2) their generalization of the sound property to a new member of a familiarized category (e.g., Animal A [blue]–Sound 1). When familiarized with a single exemplar of a category, 11-month-olds showed no evidence of acquiring or generalizing the animal–sound pairings. In contrast, 11-month-olds learnt the original animal–sound mappings and generalized the sound property to a novel member of that category when familiarized with multiple exemplars of a category. Finally, when familiarized with multiple exemplars, 9-month-old infants learnt the original animal–sound pairing, but did not extend the novel sound property. The results of these experiments provide evidence for developmental differences in the facilitative role of multiple exemplars in promoting the learning and generalization of information.