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871.
Neonates (M age = 16 days) born to depressed and non-depressed mothers were randomly assigned to hear an audiotaped lullaby of instrumental music with vocals or without vocals. Neonatal EEG and EKG were recorded for 2 min (baseline) of silence and for 2 min of one or the other music presentation. Neonates of non-depressed mothers showed greater relative right frontal EEG asymmetry to both types of music, suggesting a withdrawal response. Neonates of depressed mothers on the other hand showed greater relative left frontal EEG asymmetry to the instrumental without vocal segment, suggesting an approach response, and greater relative right frontal EEG asymmetry to the instrumental with vocal segment, suggesting a withdrawal response. Heart rate decelerations occurred following the music onset for both groups of infants, however, compared to infants of non-depressed mothers, infants of depressed mothers showed a delayed heart rate deceleration, suggesting slower processing and/or delayed attention. These findings suggest that neonates of depressed and non-depressed mothers show different EKG and EEG responses to instrumental music with versus without vocals.  相似文献   
872.
Sixty-eight preterm infants (M GA = 30 weeks) were randomly assigned to a moderate or to a light pressure massage therapy group to receive 15 massages three times per day for 5 days. Behavior state, stress behaviors and heart rate were recorded for 15 min before and during the first 15-min therapy session. Weight gain was recorded over the 5-day therapy period. The moderate versus light pressure massage group gained significantly more weight per day. During the behavior observations the moderate versus light pressure massage group showed significantly lower increases from the pre-session to the session recording on: (1) active sleep; (2) fussing; (3) crying; (4) movement; and (5) stress behavior (hiccupping). They also showed a smaller decrease in deep sleep, a greater decrease in heart rate and a greater increase in vagal tone. Thus, the moderate pressure massage therapy group appeared to be more relaxed and less aroused than the light pressure massage group which may have contributed to the greater weight gain of the moderate pressure massage therapy group.  相似文献   
873.
This article reports on a series of 5 analyses of spontaneous production of verbal inflection (tense and person–number agreement) by 2-year-olds acquiring French as a native language. A formal analysis of the qualitative and quantitative results is developed using the unique resources of Optimality Theory (OT; Prince & Smolensky, 2004). It is argued that acquisition of morphosyntax proceeds via overlapping grammars (rather than through abrupt changes), which OT formalizes in terms of partial rather than total constraint rankings. Initially, economy of structure constraints take priority over faithfulness constraints that demand faithful expression of a speaker's intent, resulting in child production of tense that is comparable in level to that of child-directed speech. Using the independent Predominant Length of Utterance measure of syntactic development proposed in Vainikka, Legendre, and Todorova (1999), production of agreement is shown first to lag behind tense then to compete with tense at an intermediate stage of development. As the child's development progresses, faithfulness constraints become more dominant, and the overall production of tense and agreement becomes adult-like.  相似文献   
874.
Previous research has emphasized the role of within-match similarity in children's comparisons. The current study investigated another potentially important contributing factor, namely the distinctiveness of the matching items relative to other items in the scene. Using a well-known relational mapping task, we found that 3- and 4-year-olds made more correct matches between identical objects when those objects were maximally distinctive from the foils. In a cross-mapping experiment, where same relative size was pitted against object similarity, 3-year-olds made more incorrect object matches when the objects were both similar to each other and distinctive from the foils. Furthermore, 3- and 4-year-olds performed the same, regardless of within-match similarity, so long as the ratios of within-match and nonmatch similarity were roughly equal. These findings suggest that children's comparisons are guided by a ratio consisting of many pairwise similarity relations, including (but not limited to) the degree of within-match similarity.  相似文献   
875.
The generality of the molar view of behavior was extended to the study of choice with rats, showing the usefulness of studying order at various levels of extendedness. Rats' presses on two levers produced food according to concurrent variable-interval variable-interval schedules. Seven different reinforcer ratios were arranged within each session, without cues identifying them, and separated by blackouts. To alternate between levers, rats pressed on a third changeover lever. Choice changed rapidly with changes in component reinforcer ratio, and more presses occurred on the lever with the higher reinforcer rate. With continuing reinforcers, choice shifted progressively in the direction of the reinforced lever, but shifted more slowly with each new reinforcer. Sensitivity to reinforcer ratio, as estimated by the generalized matching law, reached an average of 0.9 and exceeded that documented in previous studies with pigeons. Visits to the more-reinforced lever preceded by a reinforcer from that lever increased in duration, while all visits to the less-reinforced lever decreased in duration. Thus, the rats' performances moved faster toward fix and sample than did pigeons' performances in previous studies. Analysis of the effects of sequences of reinforcer sources indicated that sequences of five to seven reinforcers might have sufficed for studying local effects of reinforcers with rats. This study supports the idea that reinforcer sequences control choice between reinforcers, pulses in preference, and visits following reinforcers.  相似文献   
876.
A fairly common view holds that children's risks of negative outcomes associated with family dissolution are generally small or even nonexistent in Scandinavia, and clearly smaller than what is usually found in the United States. This view was empirically examined in a recent large-scale study of 4,127 12–15-year-old children in Norway, of whom 623 had experienced parental divorce and lived in a single-mother family. The somewhat paradoxical pattern of findings was as follows: (a) The negative associations between parental divorce and various outcomes were found to be generally very similar in Norway and the United States in spite of the great differences in family policy and welfare benefits for single mothers (at the macro level); and (b) Mediational effects of family economic resources were in both countries most marked for the academic achievement area, and the predictive power of such variables was quite similar, again in spite of the great differences in absolute level of the economic resources available to single-mother families in the two countries. The results cast some doubt on the value of the absolute economic deprivation perspective in explaining the results, and the many Norwegian welfare benefits do not seem to mitigate the association between divorce and negative outcomes for the children involved. Also policy implications derived from the economic deprivation perspective are questioned. Alternative interpretations of the findings involving relative deprivation and economic resources as a partial proxy for other non-economic factors are briefly discussed.  相似文献   
877.
Investigated whether three self-system beliefs, fear of abandonment, coping efficacy, and self-esteem, mediated the relations of stressors and caregiver–child relationship quality with concurrent and prospective internalizing and externalizing problems in a sample of children who had experienced parental death in the previous 2.5 years. The cross-sectional sample consisted of 340 children ages 7–16 and their surviving parent/current caregiver; the longitudinal analyses employed a subset of this sample that consisted of 100 children and their parents/caregivers who were assessed at three time points. A multirater, multimethod measure of caregiver–child relationship quality and a multirater measure of children's mental health problems were used. The cross-sectional model supported a mediational relation for fear of abandonment, coping efficacy, and self-esteem. The three-wave longitudinal model showed that fear of abandonment at Time 2 mediated the relation between stressors at Time 1 and internalizing and externalizing problems at Time 3. Implications of these findings for understanding the development of mental health problems in parentally bereaved children and designing interventions for this at-risk group are discussed.
Sharlene A. WolchikEmail:
  相似文献   
878.
The present study was designed to examine the processes by which grammatical gender is assigned during word production. French words varied in strength of sublexical cues, based on whether the word ending was typical for one gender rather than neutral about gender, and lexical cues, derived from the associated definite article being uninformative about gender for words beginning with a vowel, but informative for words beginning with a consonant. In Experiment 1, when native French speakers classified the gender of mentally evoked names of pictures, no effects of these cues were obtained. Experiment 2 used an improved methodology, with participants classifying the gender of words translated from English. English-speaking learners of French were influenced strongly by lexical and sublexical cues, while French speakers showed a weaker influence. However, for both speaker groups, words whose gender was classified slowly during recognition were also classified slowly during production, and error rates were similarly correlated across tasks. The conclusion was that gender is not equally available for all words once the associated “lemma” is accessed. Current models of language production may have to incorporate mechanisms allowing differential speed of access to gender information depending on a word’s formal properties.  相似文献   
879.
Although challenges of anti-racist work are most commonly framed in relation to White people and People of Color, there are significant challenges involved in creating allies across minority racial groups. This article describes our experiences within a community organization aimed at training anti-racist culturally sensitive K-12 educators. As Asian American and Native American facilitators within a group of facilitators of color who were predominantly Black, we describe our experiences of relative marginalization and our (mostly failed) attempts to create change within the organization to be more inclusive of the perspectives, experiences, and needs of non-Black people/students of color. We contextualize these experienced conflicts in relation to race hierarchies, the “divide and conquer strategy” and the maintenance of White privilege. We offer reflections for how racial minorities engaged in anti-racist education could be better allies and how organizations might better foster environments that contribute to the creation of these alliances.
  相似文献   
880.
This study evaluated the Penn Resiliency Program's effectiveness in preventing depression when delivered by therapists in a primary care setting. Two-hundred and seventy-one 11- and 12-year-olds, with elevated depressive symptoms, were randomized to PRP or usual care. Over the 2-year follow-up, PRP improved explanatory style for positive events. PRP's effects on depressive symptoms and explanatory style for negative events were moderated by sex, with girls benefiting more than boys. Stronger effects were seen in high-fidelity groups than low-fidelity groups. PRP did not significantly prevent depressive disorders but significantly prevented depression, anxiety, and adjustment disorders (when combined) among high-symptom participants. Findings are discussed in relation to previous PRP studies and research on the dissemination of psychological interventions. An erratum to this article is available at .  相似文献   
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