Sleeping position, orientation, and proximity in bedsharing infants and mothers

The impact of mother-infant bedsharing on infant sleeping position, orientation, and proximity to the mother was assessed in 12 breast-feeding Latino mother-infant pairs. Six routinely bedsharing and six routinely solitary-sleeping pairs slept 3 nights in the sleep laboratory. The first night matched the routine home condition, followed by 1 bedsharing night and 1 solitary-sleeping night in random order. During bedsharing infants were never placed prone, regardless of their routine sleeping condition. On the bedsharing night, mothers and infants spent most of the night oriented toward each other; seven of 12 infants remained oriented toward their mothers the entire night. While sleeping in a face-to-face orientation, most pairs slept most of the time less than 30 cm apart with appreciable amounts of time at less than 20 cm. This orientation and proximity should facilitate sensory exchanges between mother and infant which, we hypothesize, influence the infant's sleep physiology and nocturnal behavior. We conclude that bedsharing minimizes the use of the prone infant sleeping position, probably in part to facilitate breast feeding. By promoting nonprone positions, bedsharing may protect some infants from sudden infant death syndrome (SIDS), since prone sleeping is a known risk factor for SIDS. The large percentage of the night that mothers spent oriented toward their infants suggests that a higher degree of maternal vigilance may also result from bedsharing.     

Cosleeping (bedsharing) among infants and toddlers

This study was designed to investigate the effect of retaining coronal tooth substance on the performance of post-retained core materials, and to compare the fracture resistance of the system with an intact tooth prepared to similar dimensions. Ten teeth restored with post-retained silver amalgam, and 10 teeth restored with silver-glass cermet, all with a retained single wall of coronal tooth substance, were compared with 10 unrestored teeth prepared to similar dimensions when subjected to a shearing load. The results showed no statistically significant difference between the unrestored teeth and those restored with a silver-glass cermet. Whilst the teeth restored with silver amalgam had a significantly higher fracture resistance (P > 0.01) there was greater tendency to root fracture.     

Roles of function, reminding, and variability in categorization by 3-month-old infants.

The roles of function, reminding, and exemplar variability in categorization of a physically dissimilar object were studied with 3-month-old infants trained to move a crib mobile by kicking. Performance on a transfer test with a motionless novel object provided evidence of categorization. In Experiments 1 and 2, infants, like adults, initially categorized novel objects on the basis of physical appearance, but only if trained with multiple exemplars, after delays of 1 and 7 days. In Experiment 3, prior knowledge of an object's functional properties overrode physical dissimilarity as the basis for categorization and enabled reminding of the classification response 2 weeks later. In Experiment 4, postevent contingency information overrode physical and functional properties as the basis for categorization. These findings indicate that expectations and goals influence infants' category decisions and raise the possibility that infants of 3 months respond by analogy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Event-specific expectations of 2- and 3-month-old infants.

The Visual Expectation Paradigm (M. M. Haith et al, 1988) was modified to assess the role that picture content plays in the spatiotemporal expectations of 2- and 3-mo-old infants. Infants watched pictures of 700-msec duration that appeared in left–right alternation with a 1,000-msec interstimulus interval. The same picture occurred repeatedly on one side, in alternation with an unpredictable picture on the other side. Across 3 studies, the unchanging picture, rather than engendering habituation, produced higher levels of anticipation and speeded reactions. Thus, infants used the stable picture-content information to facilitate formation of expectations about when and where pictures would appear. Although 2-mo-olds were consistently slower than 3-mo-olds, their reaction times (RTs) benefited more from predictability than did the RTs of older infants. The percentage of anticipatory fixations did not differ between the 2 age groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Secular trends in breastfeeding and parental smoking

Over a 9-year period 37 consecutive adults with primary refractory (n = 13) or first relapse of ALL (n = 24) received an intensive salvage chemotherapy regimen with the final intention of undergoing stem cell transplantation (SCT). Twenty-nine patients who achieved complete remission (CR) were assigned to receive autologous SCT (autoSCT) or allogeneic SCT (alloSCT) based on age and availability of a histocompatible sibling. Of the 19 patients assigned to autoSCT, 10 did not reach the transplant due to early relapse (n = 9) or fungal infection (n = 1), and nine were transplanted a median of 2.5 months (1-8) from CR, eight with an immunologically purged graft. One patient died early from ARDS and eight relapsed 2-30 months post-SCT. Three of the 10 patients assigned to alloSCT relapsed early, but all 10 received the assigned transplant a median of 2.5 months (1-7) from CR. Four died from transplant-related complications 0.7-12 months post-SCT, and six are alive and disease-free 9.7-92.6 months after the procedure. In an intention-to-treat analysis, the mean overall survival from CR for those assigned to autoSCT and alloSCT are 11.3 months (0.5-34.3) and 60.1 (2.3-98.3), respectively (log-rank, P < 0.01). Only 65% of patients who reached CR and 51% of the initial 37 cases underwent the intended SCT. We conclude that few adults with refractory or relapsed ALL actually reach SCT in CR even when the protocol used is designed for this purpose. AutoSCT appears to offer little benefit in this setting, and an alloSCT from a related or unrelated donor should be rapidly pursued after achieving CR.     

Object permanence in 3?- and 4?-month-old infants.

These experiments tested object permanence in 3-12- and 4-12-month-old infants. The method used in the experiments was similar to that used by Baillargeon, Spelke, and Wasserman (1985). The infants were habituated to a solid screen that rotated back and forth through a 180° arc, in the manner of a drawbridge. Following habituation, a box was placed behind the screen and the infants were shown two test events. In one (possible event), the screen rotated until it reached the occluded box; in the other (impossible event), the screen rotated through a full 180° arc, as though the box were no longer behind it. The 4-12-month-olds, and the 3-12-month-olds who were fast habituators, looked reliably longer at the impossible than at the possible event, suggesting that they understood that (a) the box continued to exist after it was occluded by the screen and (b) the screen could not rotate through the space occupied by the occluded box. Control experiments conducted without the box supported this interpretation. The results of these experiments call into serious question Piaget's (1954) claims about the age at which object permanence emerges and about the processes responsible for its emergence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does passive smoking in early pregnancy increase the risk of small-for-gestational-age infants?

OBJECTIVES: This study tested the hypothesis that women who deliver small-for-gestational-age infants are more often exposed to passive smoking at home or at work. METHODS: Among a 1-year cohort of nulliparous women in the city of Malm?, Sweden 872 (87.7%) women completed a questionnaire during their first prenatal visit. The study was carried out among women whose pregnancies resulted in a singleton live birth (n = 826), 6.7% of infants were classified as small for their gestational age. RESULTS: Passive smoking in early pregnancy was shown to double a woman's risk of delivering a small-for-gestational-age infant, independent of potential confounding factors such as age, height, weight, nationality, educational level, and the mother's own active smoking (odds ratio [OR] = 2.7). A stratified analysis indicated interactional effects of maternal smoking and passive smoking on relative small-for-gestational-age risk. CONCLUSIONS: Based on an attributable risk estimate, a considerable reduction in the incidence of small-for-gestational-age births could be reached if pregnant women were not exposed to passive smoking.     

Object segregation in 8-month-old infants

Two experiments examined 8-month-old infants' use of configural and physical knowledge in segregating three-dimensional adjacent displays. The infants in Experiment I saw two identical yellow octagons standing side by side: in the test events, a hand grasped the right octagon and pulled it to the side. The infants looked reliably longer when the octagons moved apart than when they moved together, suggesting that the infants (a) perceived the octagons as a single unit and hence (b) expected them to move together and were surprised when they did not. The infants in Experiment 2 saw a yellow cylinder and a blue box: a hand grasped the cylinder and pulled it to the side. The infants looked reliably longer when the box moved with the cylinder than when the box remained in place, suggesting that they (a) viewed the cylinder and box as distinct units and thus (b) expected the cylinder to move alone and were surprised when it did not. These results indicate that, by 8 months of age, infants use configural knowledge when organizing adjacent displays: they expect similar parts to belong to the same unit and dissimilar parts to belong to distinct units. Additional results revealed that 8-month-old infants' interpretation of displays is affected not only by configural but also by physical consideration. Thus, infants in Experiment 1 who saw a thin blade lowered between the octagons viewed them as two rather than as one unit. Similarly, infants in Experiment 2 who saw the cylinder lying above instead of on the apparatus floor perceived the cylinder and box as one rather than two units. These results indicate that 8-month-old infants bring to bear their knowledge of impenetrability and support when parsing adjacent displays. Furthermore, when faced with two conflicting interpretations of a display, one suggested by their configural and one by their physical knowledge, infants allow the latter to supersede the former. Together, these findings suggest that, by 8 months of age infants approach to segregation is fundamentally similar to that of adults.     

The still-face effect in Chinese and Canadian 3- to 6-month-old infants

Both green and black tea have been shown to inhibit lung tumorigenesis in laboratory animal experiments. Green tea inhibited N-nitrosodiethylamine-induced lung tumor incidence and multiplicity in female A/J mice when tea was given either during the carcinogen treatment period or during the post-carcinogen treatment period. In a separate tumorigenesis model, both decaffeinated black tea and decaffeinated green tea inhibited 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumor formation. Studies in which tea was administered during different time periods in relation to the NNK suggest that tea can inhibit lung tumorigenesis at both the initiation and promotion stages. The antiproliferative effects of tea may be responsible for these anti-carcinogenic actions. Black tea polyphenol preparations decreased NNK-induced hyperproliferation. Black tea also inhibited the progression of pulmonary adenomas to adenocarcinomas and the formation of spontaneous lung tumors in A/J mice. Growth inhibition by various tea polyphenols has been demonstrated in human lung H661 and H1299 cells. Although inhibition of cell growth and signal transduction pathways by tea components have been demonstrated, the concentrations required to produce the effect are higher than achievable in tissues in vivo. More research is necessary to translate these laboratory results to applications in human chemoprevention.     

Temporal bisection in 4-month-old infants.

The present study was the first to investigate infants' ability to discriminate time using a bisection task that has been extensively used with animals and human adults. Infants aged 4 months were presented with two standard auditory signals, one short (S = 500 ms) and one long (L = 1,500 ms), and were trained either to look to the left after S and to the right after L, or vice versa. During the test phase, the infants were then presented with intermediate durations without reinforcement as well as the two reinforced standard durations, for which the reinforcement was either immediate or delayed of 3 s. The times spent by the infants looking to the right, left or away from the target after the stimulus duration were coded by two blind coders. The results revealed an orderly psychophysical function with the proportion of long responses increasing with signal duration. The point of subjective equality (Bisection Point) was closer to the geometric mean of the short and long standard duration than to their arithmetic mean. Modeling using the scalar timing models revealed that our infants had a relatively high sensitivity to time but that their temporal performance was affected by the fact that they made a large number of random responses. The development of the perception of time is discussed in the light of similarities and differences in temporal bisection performance between different species (rats and humans) and the different levels of development observed within a given species. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cross-modal transfer in 6-month-old infants.

Investigated in 4 studies with 101 infants 25.5–32 wks of age the ability of Ss to transfer information about shape across modalities. Ss were familiarized either orally or tactually and then tested for visual recognition memory. In Exp I, Ss failed to show evidence of cross-modal transfer on any of the tasks (1 oral–visual, 2 tactual–visual). When familiarization times were increased from 30 to 60 sec in Exp II, Ss showed evidence of transfer on both tactual–visual tasks. Exp III eliminated the 5–7 sec delay that generally intervenes between the familiarization and test phase. Ss were permitted to retain the stimulus in their hand (or mouth) during the test phase while simultaneously viewing a novel stimulus and a duplicate of the familiar stimulus. This modification resulted in successful transfer on 1 of the 2 tactual–visual tasks. Ss did not show evidence of transfer on the oral–visual problem in any of these studies, despite evidence from Exp IV that they could visually discriminate the paired stimuli used in these tasks and that they showed recognition memory when familiarization and testing were both visual. Results suggest that, although cross-modal transfer of information about shape is present among 6-mo-olds, it is a less robust phenomenon than that seen in older infants. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Right frontal brain activity, cortisol, and withdrawal behavior in 6-month-old infants.

Although several studies have examined anterior asymmetric brain electrical activity and cortisol in infants, children, and adults, the direct association between asymmetry and cortisol has not systematically been reported. In nonhuman primates, greater relative right anterior activation has been associated with higher cortisol levels. The current study examines the relation between frontal electroencephalographic (EEG) asymmetry and cortisol (basal and reactive) and withdrawal-related behaviors (fear and sadness) in 6-month-old infants. As predicted, the authors found that higher basal and reactive cortisol levels were associated with extreme right EEG asymmetry. EEG during the withdrawal-negative affect task was associated with fear and sadness behaviors. Results are interpreted in the context of the previous primate work, and some putative mechanisms are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Object and event representation in 6?-month-old infants.

Two experiments were conducted in which infants had to use remembered knowledge of auditory visual events to guide their reaching and grasping. The events involved a ball falling noisily through a tube and coming to rest at 1of 2 locations, with either resting site specified by distinctive auditory information. The events were presented initially in the light and then in the dark to determine whether infants would remember and use the auditory cues when they could no longer see where the ball fell. In both experiments, infants' reaching behavior was initiated and carried out after the sound ended, which ensured that search for the ball took place without support from ongoing visual or auditory cues. Accurate searching for the ball depended on infants' experience in the light. The authors conclude that 6 ?-month-olds can represent unseen objects and events and use this knowledge to guide their actions to achieve a goal. The success in this task was contrasted with the failures of infants this age in the Piagetian hidden object task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Detection of stimulus motion in 5-month-old infants.

Five-month-old infants were tested by the method of preferential looking for discrimination between a pattern undergoing oscillating apparent motion and an identical static pattern. Sensitivity to small spatial displacements was evident at temporal frequencies of 8 and 16 Hz. Preference for the moving display was related independently to the temporal frequency of oscillation and the magnitude of the spatial displacement. Preferences for the moving display increased asymptotically across spatial displacements from 11 to 89 arc min. Preferences peaked between temporal oscillation frequencies of 8 and 16 Hz. Preference was not related to the ratio of these two variables—velocity. The minimum displacement threshold of 7.36 arc min was found to depend on the size of the elements in the pattern and on the temporal frequency of oscillation. The results demonstrate that motion-sensitive mechanisms responsive to small spatial displacements are present at 5 months of age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Health effects of passive smoking. 3. Parental smoking and prevalence of respiratory symptoms and asthma in school age children

BACKGROUND: A systematic quantitative review of the evidence relating parental smoking to the prevalence of asthma and respiratory symptoms was conducted amongst school age children. METHODS: Sixty relevant studies were identified after consideration of 1593 articles selected by electronic search of the Embase and Medline databases using keywords relevant to passive smoking in children. The search was completed in April 1997 and identified 25 studies of asthma, 41 of wheeze, 34 of chronic cough, seven of chronic phlegm and six of breathlessness which were included in a quantitative overview. RESULTS: The pooled odds ratios for either parent smoking were 1.21 (95% CI 1.10 to 1.34) for asthma, 1.24 (95% CI 1.17 to 1.31) for wheeze, 1.40 (95% CI 1.27 to 1.53) for cough, 1.35 (95% CI 1.13 to 1.62) for phlegm, and 1.31 (95% CI 1.08 to 1.59) for breathlessness. Adjustment for confounding had little effect. Evidence of heterogeneity between studies appeared largely explicable by publication bias with a superfluity of small studies with large odds ratios. However, excluding these had little effect on the pooled odds ratios. The prevalence of all symptoms increased with the number of parents who smoked. While maternal smoking had a greater effect than paternal smoking, the effect of father only was clearly significant. CONCLUSIONS: The relationship between parental smoking and respiratory symptoms seems very likely to be causal given statistical significance, robustness to adjustment for confounding factors, consistency of the findings in different countries, and evidence of dose response. The raised risk in households where the father, but not the mother, smoked argues for a postnatal effect.