Posture,muscular tone and visual attention in 5 month‐old infants

The present paper aims at studying the relationships between posture, muscle tone and visual attention in 5 month‐old infants. To this end, a specially designed seating arrangement made it possible to vary posture while keeping constant the spatial relationship between eyes and stimuli. Five month‐olds were placed in the reclining position (30°) or in a more erect position (60°). The more erect the posture, the more difficult it should be for the infant to maintain a straight body axis. Muscle tone was evaluated, and infants distinguished in terms of whether they were hypertonic or hypotonic. It was hypothesised that in a more erect position hypotonic children, who experience more difficulties in maintaining posture, should organise their visual exploration in ways different from those considered to be hypertonic. To test it, pairs of three‐dimensional stimuli were presented in the distal visual field for one group (N=48) and in the proximal visual field in another group (N=32) for 2 min in each posture. The dynamical organisation of attention was evaluated through the number and duration of fixations on each target, the number of shifts from one target to the other (alternations) and the number of repetitions (back to the previous target). Results showed that visual behaviour was significantly affected by the distance at which stimuli were presented. Infants spent more time in visual exploration when the object was within reach than when it was out of reach. Although posture was shown to play a role in the organisation of visual exploration, no link with muscle tone was found, a surprising result which is discussed. Copyright © 2002 John Wiley & Sons, Ltd.     

Infants' Grasp of Others' Intentions

ABSTRACT— The perception of others as intentional agents is fundamental to human experience and foundational to development. Recent research reveals that this cornerstone of social perception has its roots early in infancy, and that it is influenced by the universal, early-emerging human experience of engaging in goal-directed action. Infants' own action capabilities correlate with their emerging tendency to view others' actions as organized by goals. Moreover, interventions that facilitate new goal-directed actions alter infants' perception of those same actions in others. These effects seem to depend on the first-person aspects of infants' experience. These findings open new questions about how doing leads to knowing in the social domain.     

Infant transfer behavior in humans: A note on the exploitation of young

Human infant transfers filmed in West New Guinea and stored in the archives of Max-Planck Geselschaft are formally described and analyzed relative to reports of similar behavior from nonhuman primates in laboratory and field studies. Motor patterns directed from one individual to another were discriminated and grouped into five categories of behavior ordered according to their relative likelihoods of “damaging aggression” [Fagen, American Naturalist, 115:858–869, 1980]. Transfers generally occurred between two females of different reproductive conditions. Most interactions were directed from the holder of the infant to the infant, demonstrating that the infant is the recipient of most nondamaging as well as potentially damaging behavior. While transfers are characterized by “aggressive restraint,” the least damaging behavior is most likely to precede a transfer and may function to prolong the relative duration of infant holding. Behavior with a relatively high likelihood of damage to the infant by the infant holder is as likely to occur before as after transfer, suggesting that infant transfer behavior in this human society reflects competitive interactions among adult females.     

Interaction between mother and pre-term infant at 34 weeks post-conceptional age

The impact of premature birth and perinatal medical status on early mother–infant interaction was assessed in 75 dyads with pre-term infants divided into three groups. Infants' gestational age at birth and need for neonatal intensive care intervention differentiated the groups: group 1, 23–31 weeks with intensive care; group 2, 32–35 weeks with intensive care; group 3, 32–35 weeks with no intensive care. The methodological approach was based on observations of the dyads performed when the infant reached a post. conceptional age of 34 weeks (4 weeks before estimated due date of delivery). The observations were conducted in the neonatal nursery during cleaning, face-to-face and feeding interactions. Significant group differences were found in infant distress, maternal sensitivity to the infant and dyadic behaviours of positive interaction. Group 1 dyads showed higher scores or more desirable performance than dyads of group 3. Group 2 dyads usually achieved intermediate scores and performed better than dyads of group 3, especially during the feeding situation. We suggest that, in addition to a possible emergence of maternal compensatory mechanisms in the higher-risk groups, the amount of dyadic experience after birth affects the quality of mother–infant interaction at this early stage.     

Effects of cocaine exposure on infant development: A review

We review the effects of maternal cocaine use on the developing human fetus and infant in terms of methodological problems; the physiological action of cocaine on adults and on the developing fetus; the epidemiology of cocaine use; effects on fetal and infant mortality; growth of cocaine-exposed fetuses and infants; physical anomalies; evidence for and against infant withdrawal from cocaine; neurological effects; behavioral effects as shown by the NBAS; findings related to mother-infant interaction and emotional development; and parenting by cocaine-using mothers. Findings in most areas should be considered preliminary due to methodological problems. Published studies of long-term development are not yet available. In general, deleterious consequences of prenatal cocaine exposure are found for some portion of prenatally exposed infants. However, many findings of no difference are also available in methodologically well-controlled studies.     

爬行与婴儿共同注意能力的发展

本研究考察了８～１１个月婴儿共同注意能力的发展趋势以及爬行与其发展的关系。结果表明：１）一岁以内的婴儿在共同注意时有仅跟视相同方向与准确定位他人注视点两种不同水平的表现,这两种表现具有不同的发展趋势;２）影响婴儿共同注意时仅跟视相同方向水平发展的主要因素是婴儿的年龄,爬行时间的效应不显著;３）对婴儿准确定位的发展而言,影响其发展的重要因素是婴儿的爬行而不是婴儿的年龄。     

Conditions for Piagetian Stage IV search errors in a task using transparent occluders

In a Piagetian Stage IV search task in which the object was in plain view under transparent covers, Butterworth (1977) obtained errors from nearly half the infants but noted few errors when the object was uncovered. This study investigates the possibility that errors arise in the former case because novel transparent covers present a particular distraction. Butterworth's results with transparent covers were replicated under his conditions of administration, but virtually no errors were obtained when infants were familiarized with the covers prior to testing. From this and other results it is suggested that errors in search for a visible object only occur when the infant's attention is drawn by other features of the array.     

Relevance of physical environment influences for toddler temperament

The present study investigated the relation of the physical environment to toddler and parent temperament. Measurement of the physical environment offers a unique way of disentangling environmental influences on temperament from child influences on the environment. Subjects were 82 12-month-old toddlers. The physical environment was assessed during six separate home observations, using codes from the Purdue Home Stimulation Inventory. Toddler temperament was measured by the Toddler Temperament Scale, and maternal temperament was assessed with the revised Dimensions of Temperament Scale. Results indicated that measures of crowding and availability of objects and visual stimuli were most consistently related to specific dimensions of toddler temperament. Relations between physical environment and maternal temperament were inconsistent. Partialling out maternal temperament did not substantially change observed relations between the physical environment and toddler temperament. Implications of these findings for our understanding of environmental contributions to the expression of temperament are discussed.