Motor development during the first 6 months: the case of Brazilian infants

This investigation documents the pattern of motor development of Brazilian infants over the first 6 months and compares the findings with a US norm. Infants were assessed once each month for the 6‐month period using the Bayley II Motor Scale, which represented the US norm for comparison. Participants monthly scores increased with age and were similar to the US profile. However, the Brazilian infants did exhibit mean scores significantly lower than their counterparts on tasks of sitting and grasping in the 3rd, 4th, and 5th month; at the 6th month, scores were comparable. Explanations for differences focus on possible cross‐cultural and maturational influences. Copyright © 2000 John Wiley & Sons, Ltd.     

Language skills of children during the first 12 months after stuttering onset

PurposeTo describe the language development in a sample of young children who stutter during the first 12 months after stuttering onset was reported.MethodsLanguage production was analysed in a sample of 66 children who stuttered (aged 2–4 years). The sample were identified from a pre-existing prospective, community based longitudinal cohort. Data were collected at three time points within the first year after stuttering onset. Stuttering severity was measured, and global indicators of expressive language proficiency (length of utterances and grammatical complexity) were derived from the samples and summarised. Language production abilities of the children who stutter were contrasted with normative data.ResultsThe majority of children’s stuttering was rated as mild in severity, with more than 83% of participants demonstrating very mild or mild stuttering at each of the time points studied. The participants demonstrated developmentally appropriate spoken language skills comparable with available normative data.ConclusionIn the first year following the report of stuttering onset, the language skills of the children who were stuttering progressed in a manner that is consistent with developmental expectations.     

Differences in caregiver behaviors of infants at-risk for autism and typically developing infants from 9 to 15 months of age

During an object sharing paradigm, we compared infant-caregiver interactions between two groups: i) infants at high-risk (HR) for being diagnosed with Autism Spectrum Disorder (ASD) and ii) low-risk (LR) infants, observed at 9, 12, and 15 months of age. 16 HR infants (14 infants with an older sibling diagnosed with ASD and 2 preterm infants that received a diagnosis of ASD at 2 years) and 16 LR infants (typically developing infants without older siblings diagnosed with ASD) were included in the study. At each visit, infants played with objects in the presence of their caregivers as crawlers or walkers. Previously, we found that HR infants are less likely to share their object play with caregivers at walker ages. The present study found that caregivers of HR infants used greater directive bids including being more proximal to infants and using greater verbal and non-verbal bids to sustain their infant’s attention and to ensure their compliance during the task compared to caregivers of LR infants. Our study emphasizes the bidirectional and dynamic nature of infant-caregiver interactions. Our findings have implications for caregiver training programs that teach parents appropriate strategies to promote early social communication skills in at-risk infants.     

Identifying the level of trunk control of healthy term infants aged from 6 to 9 months

This study identified the level of trunk control of healthy term infants aged from six to nine months. This cross-sectional study included fifty-five infants aged from six to nine months. The levels of trunk control was investigated by using the Segmental Assessment Trunk Control (SATCo). The infants remained seated on a wooden bench and a neutral pelvic position was maintained. The SATCo score was considered as dependent variable. The results showed that infants aged six and seven months presented levels of trunk control in the thoracic region while infants aged from eight to nine months presented full trunk control. These results demonstrate that younger infants present less levels of trunk control while older infants present full trunk control, confirming that trunk control development takes place in a segmental way and in a cephalocaudal direction. These results also might be used as a reference to distinguish infants that show a delay in trunk control from those who have suitable motor development and, thus intervene at an early stage to minimize later delays in these infantś global motor development.     

Differences in object sharing between infants at risk for autism and typically developing infants from 9 to 15 months of age

Object sharing abilities of infants at risk for autism (AR infants) and typically developing (TD) infants were compared from 9 to 15 months of age. Specifically, we examined the effects of infants’ locomotor abilities on their object sharing skills. 16 TD infants and 16 AR infants were observed during an “object sharing” paradigm at crawling and walking ages. Overall, AR walking infants demonstrated lower rates of object sharing with caregivers compared to TD walking infants. Specifically, AR walking infants had lower rates of giving and approaches toward caregivers compared to TD walking infants. AR walking infants also had lower step rates toward task-appropriate targets, i.e. caregivers and objects compared to TD walking infants. No group differences in object sharing were observed at crawling ages. Object sharing could be a valuable context for early identification of delays in infants at risk for developing Autism spectrum disorder.     

Infant vocal development during the first 6 months: speech quality and melodic complexity

The early development of infant non‐distress vocalizations was investigated in this study. Thirteen infants, from 4 to 24 weeks of age, and their mothers were observed weekly in a face‐to‐face interaction situation. The speech quality (syllabic versus vocalic) and melodic complexity (simple versus complex) of infant vocalizations were coded independently. Based on speech quality and melodic complexity, four types of infant non‐distress vocalizations were categorized: simple and complex syllabic (speech‐like) vocalizations as well as simple and complex vocalic (non‐speech‐like) vocalizations. Results showed that complex syllabic sounds were of longer duration and complex vocalic sounds were less frequent than the other types of vocalizations. Curvilinear developmental trends were found in the rate of simple vocalic sounds and in the mean duration of complex syllabic sounds. Furthermore, before 4 months of age, vocalic sounds were more likely to be associated with simple melodic contours, after which syllabic sounds were more likely to be associated with complex melodic contours. A dynamic systems perspective on the early development of infant vocalization is discussed. Copyright © 2000 John Wiley & Sons, Ltd.     

Stability and transitions in mother-infant face-to-face communication during the first 6 months: a microhistorical approach

In this study the authors attempted to unravel the relational, dynamical, and historical nature of mother-infant communication during the first 6 months. Thirteen mothers and their infants were videotaped weekly from 4 to 24 weeks during face-to-face interactions. Three distinct patterns of mother-infant communication were identified: symmetrical, asymmetrical, and unilateral. Guided by a dynamic systems perspective, the authors explored the stability of and transitions between these communication patterns. Findings from event history analysis showed that (a) there are regularly recurring dyadic communication patterns in early infancy, (b) these recurring patterns show differential stabilities and likelihoods of transitions, (c) dynamic stability in dyadic communication is shaped not only by individual characteristics (e.g., infant sex and maternal parity) but also by the dyad's communication history, and (d) depending on their recency, communication histories varying in temporal proximity exert differential effects on the self-organization processes of a dyadic system.     

Spontaneous startle activity in newborn infants

Spontaneous startles have been reported to occur most frequently in quiet sleep, less frequently in active sleep and drowse, and relatively nonexistent in the waking states. These findings may be a result of a focus on infants whose prenatal histories reflect a restricted range of the conditions to which normal newborns are exposed. The present study examined the spontaneous startle behavior of 30 newborn infants characterized by high numbers of obstetric complications and by indicators of prenatal malnutrition, but within the range of normal, healthy newborns. In this sample, startles were not limited to the sleep and drowse states. Because individual differences in a number of neonatal behaviors have been related to autonomic nervous system (ANS) functioning, the different pattern of spontaneous startles observed in this sample may be related to the functional integrity of this system.     

Changes in infant directed speech in the first six months

The Mother–Infant Phonetic Interaction model (MIPhI) predicts that, compared with adult directed speech (ADS), in infant directed speech (IDS) vowels will be overspecified and consonants underspecified during the infants' first 6 months. In a longitudinal natural study, six mothers' ADS and IDS were recorded on 10 occasions during the first 6 months after their infants were born. Acoustic–phonetic measures, including the first two formant frequencies and duration for vowels and the duration of the fricative /s/, were used to test the MIPhI model with differences between IDS and ADS during the infants' first 6 months. Repeated measures analyses showed the fricative /s/ duration was stably longer in IDS, corresponding to an overspecification throughout the 6 months. The unexpected smaller vowel space for IDS than ADS was stably maintained over the six months, suggesting an underspecification of vowels. Vowel duration, which was generally longer in IDS than ADS, however, changed over time, decreasing in difference between IDS and ADS during month 3 and 4. Results invite adjustments to the MIPhI model, in particular related to infants' needs for perceptual enhancement of speech segments, and to the course of infant neurological and communicative development throughout the first 6 months. Copyright © 2006 John Wiley & Sons, Ltd.     

The effects of the contingence during the visual habituation task in 3 and 6 months old infants]

Thirty-six 3-month old infants and the same number of 6-month old infants underwent three visual habituation procedures differentiated by degree of behavioural contingency. Results showed significant differences between conditions only for the six-month olds: the lower the contingency, the higher the visual fixation scores. Results support some of the propositions that Gergely and Watson (1996, 1999) have put forth regarding the developmental model for detecting contingencies. The results also challenge the traditional model for visual habituation which suggests that varied durations of visual fixation should basically be determined by the visual characteristics of the stimulus.     

The Gesell developmental schedule in hispanic low-birth weight infants during the first year of life

The Gesell Schedule was administered to 143 low birthweight, high-risk, Hispanic infants of low-socioeconomic status to determine if this test was appropriate for this population. All but 5 were preterms, 73 females, 70 males. The infants were evaluated at 20 and 40 weeks corrected chronological age (CCA). The Gesell appears to be a useful developmental test for this population. Values for the overall developmental quotient (DQ) did not deviate from the Gesell norms, despite the infants' relatively poor growth pattern. Slight deviations from the norm in gross motor, fine motor, and language subscales were observed at 40 weeks CCA. Repeated measure analyses of variance revealed a significant decline in overall developmental, language, and fine motor quotients from 20 to 40 weeks. Birth-weight (BW) and small-for-gestational-age (SGA) categories influenced the outcome.     

Changes in mechanical control of movement during the first 5 months of independent walking: a longitudinal study

Insight into neuromuscular control of movement is gained through an understanding of the mechanical causes of movement. Data on new walkers' net joint moments is scarce, however, although those moments can be considered the direct cause of movement. The authors' goal in this research project was to characterize net joint moments in toddlers (N = 10) during the first 5 months of independent walking and to discuss their role in mechanical control of walking. The authors modeled leg segments as oscillating pendulums fixed at the proximal joint and investigated the relationship between force and movement. Their investigation revealed that at the onset of independent gait, walking was primarily hip driven. Furthermore, the toddlers seemed to experience problems in uncoupling active and passive control around the joints. Changes in mechanical control of walking were observed after 3 to 4 months of independent walking. The changes were more obvious at the hip and the knee joint than at the ankle.     

Maternal self-confidence during the first four months postpartum and its association with anxiety and early infant regulatory problems

Maternal self-confidence has become an essential concept in understanding early disturbances in the mother-child relationship. Recent research suggests that maternal self-confidence may be associated with maternal mental health and infant development. The current study investigated the dynamics of maternal self-confidence during the first four months postpartum and the predictive ability of maternal symptoms of depression, anxiety, and early regulatory problems in infants. Questionnaires assessing symptoms of depression (Edinburgh Postnatal Depression Scale), anxiety (State-Trait Anxiety Inventory), and early regulatory problems (Questionnaire for crying, sleeping and feeding) were completed in a sample of 130 women at three different time points (third trimester (T1), first week postpartum (T2), and 4 months postpartum (T3). Maternal self-confidence increased significantly over time. High maternal trait anxiety and early infant regulatory problems negatively contributed to the prediction of maternal self-confidence, explaining 31.8% of the variance (R = .583, F_3,96 = 15.950, p < .001).Our results emphasize the transactional association between maternal self-confidence, regulatory problems in infants, and maternal mental distress. There is an urgent need for appropriate programs to reduce maternal anxiety and to promote maternal self-confidence in order to prevent early regulatory problems in infants.     

Cortisol reactivity and negative affect among preterm infants at 12 months during a mother-infant interaction task

The purpose of this study was to investigate correlates of preterm (PT) infant’s cortisol reactivity and the association to infant negative affect, during a mother-infant interaction procedure. Participants included 48 infants born prematurely (gestational age < 37 weeks) and their mothers, assessed when infants were 12 months old corrected for prematurity. The examined variables comprised both neonatal and environmental dimensions including maternal interactive behavior. Infant negative affect and maternal interactive behavior were assessed with a standardized mother-infant interaction task. A baseline infant saliva sample was collected before the interaction began, and a second sample after the interaction episodes ended. Results revealed that decrease of infant’s cortisol concentration was significantly associated with the exposure to more sensitive, and less intrusive maternal behaviors. However, once controlled for neonatal risk, family SES and maternal psychological distress, the associations were rendered non-significant. Although the association between cortisol reactivity and negative affect trended toward significance, maternal intrusiveness was the only significant predictor of observed infant negative affect. Findings suggest the importance of primary relational experiences on PT infants' early regulatory competencies.     

Parent-child interaction during the first year of life in infants at elevated likelihood of autism spectrum disorder

Autism spectrum disorder (ASD) likely emerges from a complex interaction between pre-existing neurodevelopmental vulnerabilities and the environment. The interaction with parents forms a key aspect of an infant’s social environment, but few prospective studies of infants at elevated likelihood (EL) for ASD (who have an older sibling with ASD) have examined parent-child interactions in the first year of life. As part of a European multisite network, parent-child dyads of free play were observed at 5 months (62 EL infants, 47 infants at typical likelihood (TL)) and 10 months (101 EL siblings, 77 TL siblings). The newly-developed Parent-Infant/Toddler Coding of Interaction (PInTCI) scheme was used, focusing on global characteristics of infant and parent behaviors. Coders were blind to participant information. Linear mixed model analyses showed no significant group differences in infant or parent behaviors at 5 or 10 months of age (all ps≥0.09, d≤0.36), controlling for infant’s sex and age, and parental educational level. However, without adjustments, EL infants showed fewer and less clear initiations at 10 months than TL infants (p = 0.02, d = 0.44), but statistical significance was lost after controlling for parental education (p = 0.09, d = 0.36), which tended to be lower in the EL group. Consistent with previous literature focusing on parent-infant dyads, our findings suggest that differences between EL and TL dyads may only be subtle during the first year of life. We discuss possible explanations and implications for future developmental studies.     

Effects of nutritive and non-nutritive sucking on infant heart rate variability during the first 6 months of life

The effects of eating on heart rate variability (HRV) differ between adults and newborns. This may reflect the impact of suckling on the overall psychophysiological and autonomic nervous system maturation. The purpose of the present study was to explore whether the reactions of HRV during feeding change towards the adult pattern during the first 6 months of life. In addition, the effects of non-nutritive and nutritive sucking on heart rate (HR) and HRV were compared. The participants were 23 infants on whom recordings were performed as newborns and at 6, 12 and 24 weeks old. Nutritive sucking caused an increase in HR and a decline in HRV. The results were consistent with previous reports of a decrease in high frequency components of HRV during feeding in newborns, reflecting a decrease in parasympathetic activity. This response was apparent in all four ages studied, and remained similar throughout the 6-month period. However, age as an independent factor seemed to influence both HR and HRV. Pacifier sucking had no significant effects on HRV at any age. The results demonstrate the physical strain that sucking imposes on the baby, with a specific autonomic nervous system response involved. We consider this response an essential part of the overall psychophysiological maturation of infants.     

论文王卦位的形成及其与《易经》的关系

文王卦位是以中国原有的时空观念为基础,适应占筮需要形成的.最迟在西周之时,先后形成了四时与四方相配的时空统一观念,以及五行顺次相生观念.文王卦位的安排,首先是将四时与四方相配延展为八个时段与八方一一相配,然后据八卦的卦象、卦德排定其时位与方位,理解时位是理解卦位的关键.在卦位的安排中,很可能已考虑到五行的循环相生.这种卦位说形成于古经<周易>成书前,<易经>在观象系辞中利用了这种卦位说.