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951.
The aim of this work was to examine individual differences in referential and expressive style through a longitudinal study. The composition of the first 50 words, communicative gestures, the conversational style of dyads and the percentage of vocabulary produced from 12 to 24 month-olds were analyzed. The vocabulary was collected through interviews to parents and sessions of mother-infant interaction in the laboratory. Significant differences in the proportion of common nouns and frozen phrases between referential and expressive children in the frequency of communicative gestures and style conversation were found. Thus, referential children and their mothers used more pointing gestures than the expressive children and their mothers. Additionally, mothers of referential children used completing more frequently. 相似文献
952.
The aim of this study was to analyze sexual behaviors and attitudes of children 9-14 years old in Spain. In this article we present data from 470 children of which 52% are boys and 48% girls. In order to evaluate the sample, Information, Attitudes and Behaviors related to Health Questionnaire (CIACS-II) was used. Results evidence that boys 9 years old already show behaviors that evidence their interest towards sexuality. 8% have sometimes masturbated and 9% have used pornography for becoming excited. 14% of children 11-12 years old have already had sexual relations and 38% state to have sexual fantasies. Girls start to masturbate and to have sexual relations later than boys and show a prevalence of sexual fantasies and use of pornography very lower. It is necessary sexual education programs to be implanted since early ages in schools. 相似文献
953.
We present the results of a principal-components analysis of the Personality Adjective Check List (PACL) at the item level, rather than at the scale level. The PACL was constructed by Strack (1987) to evaluate the personality scales proposed by Millon (1981). Data were obtained from a sample of normal adolescents. A scree test was applied to determine the number of factors to be extracted, and the retained factors were then rotated using a varimax procedure. Using the data from this second analysis, congruence coefficients were calculated by correlating the factor weights from the two analyses of men and women. Results reveal the existence in the whole sample of five unipolar personality factors, which we have called: Aggressive, Conscientious, Inhibited, Impulsive and Gregarious. These are not similar to those obtained from a sample of normal adults. 相似文献
954.
This study explores whether the brain can discriminate degrees of semantic congruency during wakefulness and sleep. Experiment 1 was conducted during wakefulness to test degrees of congruency by means of N400 amplitude. In Experiment 2, the same paradigm was applied to a different group of participants during natural night sleep. Stimuli were 108 sentences (definitions with two attributes) with four possible degrees of congruence as ending targets. In both studies, the amplitude of N400-like effect showed modulation according to the degree of congruency. The results indicate that the brain can accomplish sentential semantic discriminations not only in wakefulness but also in sleep. 相似文献
955.
This exploratory study examined frequency of self-reported cervical and breast cancer screening rates in a multiethnic sample of 331 female university students. In general, rates of lifetime screening were fairly low, with only 41% reporting having ever had a PAP examination and 44% reporting having undergone at least one clinical breast examination. Screening rates differed by ethnicity. Non-Hispanic White and African-American women had higher screening rates than Asian/Pacific Islander and Latina women. The significantly lower rate of screening among the latter groups is of particular concern given the higher cancer mortality rates typically observed in those groups. 相似文献
956.
Vibrotactile intensity and frequency information in the pacinian system: a psychophysical model 总被引:1,自引:0,他引:1
The objective of the study was to characterize the Pacinian representation of stimulus waveform. Subjects were presented with pairs of high-frequency vibrotactile stimuli that varied in intensity and/or frequency content and made same-different judgments under conditions of low-frequency adaptation designed to minimize the contribution of the RA system. We wished to infer the nature of the information conveyed by the Pacinian system about the stimuli from measured sensitivity (d') to stimulus differences. We first tested the hypothesis that the Pacinian system conveys only intensive information about vibratory stimuli and found that intensive cues could not account for much of the variance in the discrimination data. We then proposed a model characterizing the Pacinian-mediated representation of an arbitrary stimulus as a pattern of activation in a set of frequency-tuned minichannels. The model was shown to predict the discriminability of the stimulus pairs presented in the psychophysical experiments. Furthermore, the model parameters, optimized to fit the discrimination data, were compatible with analogous values obtained in other experimental contexts. One of the assumptions underlying the model is that information about individual spectral components is conveyed in parallel and quasi-independently. By simulating the response of a population of Pacinian afferents to a polyharmonic stimulus, we demonstrated that such a population can simultaneously convey information about multiple frequency components, despite having a homogeneous spectral profile. 相似文献
957.
This study explores the effects of a youth enrichment program on academic motivation and engagement. Fifty-three students aged 14–16 years participated in the Rotary Youth Program of Enrichment (RYPEN). Embedded within the program were workshops revolving around the Student Motivation and Engagement Wheel [Martin (2003a). How to motivate your child for school and beyond. Sydney: Bantam] and strategies aimed at enhancing students’ academic motivation and engagement. Motivation was measured using the Student Motivation and Engagement Scale [Martin (2001). Australian Journal of Guidance and Counselling 11, 1–20; Martin (2003b) Australian Journal of Education, 14, 34–49] at the outset of the program, towards the end of the program, and again 6–8 weeks later. Data showed that there were gains on key facets of students’ motivation by the end of the program – gains that were sustained 6–8 weeks later. These gains were demonstrated by boys and girls. Moreover, when compared to a larger weighted sample (2769 high school students), by Time 2 and also by Time 3, significant declines in motivation had been reversed and any pre-existing advantages or parallel strengths of the RYPEN sample over the weighted sample were maintained. Five facets of the program proposed to have contributed to its effectiveness are: the optimistic expectations held by adults, the program’s focus on mastery, the climate of cooperation and the ensuing sense of belonging, the positive relationships that developed amongst students and between students and adults, and embedding school-related elements within a broader enrichment program. Each of these is discussed. 相似文献
958.
Buenhombre Jhon Daza-Cardona Erika Alexandra Sousa Pêssi Gouveia Amauri Cajiao-Pachón María Nelly 《Animal cognition》2023,26(2):563-577
Animal Cognition - Environmental enrichment in zebrafish generally reduces anxiety-related behaviours, improves learning in maze trials and increases health and biological fitness. However, certain... 相似文献
959.
Ricardo F. Muñoz Yu-Wen Ying Guillermo Bernal Eliseo J. Pérez-Stable James L. Sorensen William A. Hargreaves Jeanne Miranda Leonard S. Miller 《American journal of community psychology》1995,23(2):199-222
The prevention of major depression is an important research goal which deserves increased attention. Depressive symptoms and disorders are particularly common in primary care patients and have a negative impact on functioning and well-being comparable with other major chronic medical conditions. The San Francisco Depression Prevention Research project conducted a randomized, controlled, prevention trial to demonstrate the feasibility of implementing such research in a public sector setting serving low-income, predominantly minority individuals: 150 primary care patients free from depression or other major mental disorders were randomized to an experimental cognitive-behavioral intervention or to a control condition. The experimental intervention group reported a significantly greater reduction in depressive levels. Decline in depressive levels was significantly mediated by decline in the frequency of negative conditions. Group differences in the number of new episodes (incidence) of major depression did not reach significance during the 1-year trial. We conclude that depression prevention trials in public sector primary care settings are feasbile, and that depressive symptoms can be reduced even in low-income, minority populations. To conduct randomized prevention trials that can test effects on incidence with sufficient statistical power, subgroups at greater imminent risk have to be identified. 相似文献
960.
A O?a 《Perceptual and motor skills》1990,71(1):35-43
The effect of different attentional strategies on motor efficiency, measured by reaction-response time components, has historically been based on memory-drum construct theory, which implied limited attention and motor-response processing. The present study contrasts these principles by using a recording system and automatic analysis of reaction-response parameters. A within-subject design allowed detailed observation of the frequency of each preparatory set within each parameter and with control of the effects of practice. Analysis indicates (a) practice changes the effects of the attentional strategies on the components of reaction response but not the actual movement; (b) the motor-set strategy produces shorter movement times and, inversely, higher motor reaction times; and (c) the motor-sensory set integrated strategy produces improvements on each component of the reaction response. These findings suggest the memory-drum construct theory needs revision and should be based on other attentional models. 相似文献