记忆自然恢复的多高峰现象与记忆保持的生理节律论

以５．５～６岁幼儿为对象,自１９８９—１９９１年用三种不同性质学习材料,进行三次实验。有效被试人数为２６８,５７３,３６６人。表明学习后４０天内多次呈现记忆自然恢复高峰。１９９２年数学实验表明学习后第７天复习（高峰期）的长时记忆效果优于第５天（低谷期）。现有记忆理论无法解释本现象。提出了以学习为始点的生理活动节律对保持材料自动加固的理论。     

Bayley‐III: Cultural differences and language scale validity in a Danish sample

The purpose of this study was to investigate cultural differences between Danish and American children at 2 and 3 years as measured with the developmental test Bayley‐III, and to investigate the Bayley‐III Language Scale validity. The Danish children (N = 43) were tested with the Bayley‐III and their parents completed an additional language questionnaire (the MacArthur‐Bates CDI). Results showed that scores from the Danish children did not differ significantly from the American norms on the Cognitive or Motor Scale, but the Danish sample scored significantly higher on the Language Scale. A comparison of the Bayley‐III Language subtests with the CDI showed that the two measures correlated significantly, but the percentile score from the CDI was significantly higher than the percentile score from the Bayley‐III Language subtests. This could be because the two instruments measure slightly different areas of language development, or because the Bayley‐III overestimates language development in Danish children. However, due to the limitations of the current study, further research is needed to clarify this issue.     

Observing videos of a baby crying or smiling induces similar,but not identical,electroencephalographic responses in biological and adoptive mothers

It is well-known that adoptive mothers respond to cues from their babies in similar ways to biological mothers, and that cortical processing is critical for adequate motive–emotional maternal responses. This study used electroencephalographic activity (EEG) to characterize prefrontal, parietal and temporal functioning in biological mothers (BM), adoptive mothers (AM), and non-mothers (NM), while viewing videos of a baby smiling or crying. The BM presented higher absolute power (AP) in the delta and theta bands (associated with pleasant, positive emotional experiences) in the frontal and parietal areas under all conditions. In response to the smiling video, both types of mothers presented a lower AP in alpha1 in the three cortices (indicative of increased attention) and, mainly in temporal areas, a higher AP in the fast frequencies (beta and gamma, reflecting increased alertness to sensory stimuli and cognitive processing). This EEG pattern in the BM and AM could reflect the greater attention and, probably, the positive mood caused by the smiling video, showing that both are sensitive to these pleasant stimuli. When viewing the video of a baby crying, the AM had higher AP in the fast frequencies (temporal and parietal areas), indicating that they were more reactive to this unpleasant video, while the NM presented only a lower AP in alpha1 in all cortices, a finding that could be associated with the general activation induced by these unpleasant stimuli as a consequence of their lack of maternal experience. These findings should help improve our understanding of the neural mechanisms involved in the processing of sensorial stimuli that establish affective-emotional links during motherhood.     

MATERNAL SELF‐REPORTED DEPRESSIVE SYMPTOMS AND MATERNAL CORTISOL LEVELS INTERACT TO PREDICT INFANT CORTISOL LEVELS

Three basic findings have emerged from research on maternal depressive symptoms and offspring hypothalamic–pituitary–adrenal functioning: (a) Mothers’ depressive symptoms are positively associated with their offsprings’ cortisol stress response, (b) numerous individual and interpersonal maternal characteristics moderate this association, and (c) maternal and infant cortisol levels are highly correlated. In combination, these findings have suggested that maternal cortisol levels may moderate the relation between maternal depressive symptoms and infant cortisol responsivity; the current study assessed this hypothesis. Participants were 297 mother–infant dyads who were recruited from the community. Maternal depressive symptoms were assessed via self‐report. Dyads participated in two differentially stressful infant challenges when infants were 16 and 17 months old. Mother and infant salivary cortisol was collected before and after challenges. Results indicate that maternal cortisol levels moderated associations between maternal depressive symptoms and infant cortisol levels across both challenges. Infants showed higher cortisol levels if their mothers had both higher depressive symptoms and higher cortisol levels, as compared to infants of mothers with higher depressive symptoms and lower cortisol, and to infants of mothers with lower depressive symptoms and either higher or lower cortisol levels. We discuss findings in relation to environmental and biological factors that may contribute to the intergenerational transmission of depressive symptoms.     

Pabiku and Ga Ti Ga: Two Mechanisms Infants Use to Learn About the World

Some of the things that adults learn about language, and about the world, are very specific, whereas others are more abstract or rulelike. This article reviews evidence showing that infants, too, can very rapidly acquire both specific and abstract information, and considers the mechanisms that infants might use in doing so.     

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.     

Maternal representation and care of infant sleep

Maternal reports about infant sleep care and ideas about the causes of awakening were obtained from telephone interviews with 104 middle class primiparae when their infants were 1 month and 1 year old. These reports were compared with their expectations about infant sleep before the birth of their child. It was found that most of the mothers were willing to ‘help’ their infants fall asleep, with 19 different kinds of techniques being spontaneously mentioned. Most of the techniques involved physical contact. The changes in technique from before birth to the end of the first year of life mainly concerned a decrease in the use of techniques involving holding the infant in the arms. From 1 month to 1 year, there was a decrease in rocking techniques, while at 1 year the use of a (bottle) feeding technique and taking the child into the parents' bed became apparent. The reasons mothers gave for infant awakenings varied from 1 month to 1 year. At 1 year, the most frequent reason was that the infant has ‘sufficient sleep’. Mothers' representations before the infant birth did not overlap with representations and reports of sleep handling after birth. Mothers were willing to apply and use a great variety of caring techniques that they perceived to be adjusted to the individual needs of their child. © 1998 John Wiley & Sons, Ltd.