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181.
182.
Jotkowitz A 《The American journal of bioethics : AJOB》2004,4(4):41-2; discussion W35-7
183.
Jotkowitz AB 《The American journal of bioethics : AJOB》2004,4(3):62-3; discussion W32
184.
The aim of the study was to examine the relationship between body esteem and body fat in British school children. Two hundred and seventy seven, 11–14-year-old children from central England took part in the study. Body esteem was measured using the Body Esteem Scale for children and percent body fat was determined by skin-fold measures. Results indicate that body esteem and adiposity were negatively related for the whole sample, for boys and girls and for White children, Black children and Asian children. Factorial ANOVA also indicated differences in body esteem according to gender and ethnicity. Boys and Black children had significantly higher body esteem than girls and Asian children respectively. Differences in body fat were also evident according to gender with boys being leaner than girls. No differences in body esteem or body fat were evident across school years. 相似文献
185.
Sroufe LA 《Developmental psychology》2003,39(3):413-6; discussion 423-9
Ainsworth's system of classifying patterns of attachment behavior has served the field well and will not be easily displaced--not because of a commitment by attachment researchers to the taxonomic status of these categories but rather because of difficulties lying in the way of a dimensional approach. Foremost among these is the large number of dimensions used in making classifications and the need to develop reliable scales to tap them. Other problems include the need to capture how behavior changes across age and across the episodes of the Strange Situation. Others will debate R.C. Fraley and S.J. Spieker's (2003) arguments concerning taxonomic status. However, whether taxa or not, Ainsworth's categories at the least have represented well the multidimensional space underlying attachment behavior in conditions of mild stress. Only when an alternative approach is demonstrated to predict (with equal power, in practice) the vast range of outcomes associated with Ainsworth's categories will it be a candidate for substitution. 相似文献
186.
Withdrawal symptoms following cessation of heavy cannabis (marijuana) use have been reported, yet their time course and clinical importance have not been established. A 50-day outpatient study assessed 18 marijuana users during a 5-day smoking-as-usual phase followed by a 45-day abstinence phase. Parallel assessment of 12 ex-users was obtained. A withdrawal pattern was observed for aggression, anger, anxiety, decreased appetite, decreased body weight, irritability, restlessness, shakiness, sleep problems, and stomach pain. Onset typically occurred between Days 1-3, peak effects between Days 2-6, and most effects lasted 4-14 days. The magnitude and time course of these effects appeared comparable to tobacco and other withdrawal syndromes. These effects likely contribute to the development of dependence and difficulty stopping use. Criteria for cannabis withdrawal are proposed. 相似文献
187.
Over the past decade, behavior analysts have increasingly used the term establishing operation (EO) to refer to environmental events that influence the behavioral effects of operant consequences. Nonetheless, some elements of current terminology regarding EOs may interfere with applied behavior analysts' efforts to predict, control, describe, and understand behavior. The present paper (a) describes how the current conceptualization of the EO is in need of revision, (b) suggests alternative terms, including the generic term motivating operation (MO), and (c) provides examples of MOs and their behavioral effects using articles from the applied behavior analysis literature. 相似文献
188.
Farroni T Mansfield EM Lai C Johnson MH 《Journal of experimental child psychology》2003,85(3):199-212
It has been hypothesized that an evolutionarily ancient mechanism underlies the ability of human infants to detect and act upon the direction of eye gaze of another human face. However, the evidence from behavioral studies with infants is also consistent with a more domain-general system responsive to the lateral motion of stimuli regardless of whether or not eyes are involved. To address this issue three experiments with 4-month-old infants are reported that utilize a standard face-cueing paradigm. In the first experiment an inverted face was used to investigate whether the motion of the pupils elicits the cueing effect regardless of the surrounding face context. In the second experiment pupil motion and eye gaze direction were opposed, allowing us to assess their relative importance. In a third experiment, a more complex gaze shift sequence allowed us to analyse the importance of beginning with a period of mutual gaze. Overall, the results were consistent with the importance of the perceived direction of motion of pupils. However, to be effective in cueing spatial locations this motion needs to be preceded by a period of direct mutual gaze (eye contact). We suggest that evolution results in information-processing biases that shape and constrain the outcome of individual development to eventually result in adult adaptive specializations. 相似文献
189.
The authors investigated whether older adults (n = 16; mean age = 65 years) increased grip force to compensate for load force fluctuations during up and down movements more than young adults did (n = 16; mean age = 24 years) and whether older and young adults exhibited similar adaptation of grip force to alterations in friction associated with changes in object surface texture. As previously reported, older adults used a higher level of grip force than young adults during static holding. Increased grip force was observed in the older group during movement. The increase was appropriate to the lower coefficient of friction estimated for the older group. In both groups, grip force was greater with a smooth than with a rough surface (the latter having the higher coefficient of friction) during static holding and during movement. Moreover, grip force modulation was equally well synchronized with load force fluctuation during movement in the two groups. The authors concluded that changes in organization of grip force with age are well adapted to change in hand-object interface properties. Elevated grip force in older adults does not necessarily signify a fundamental change in synchronizing grip force modulation with load force fluctuation. 相似文献
190.
Brown AS 《Psychological bulletin》2003,129(3):394-413
For more than a century, the déjà vu experience has been examined through retrospective surveys, prospective surveys, and case studies. About 60% of the population has experienced déjà vu, and its frequency decreases with age. Déjà vu appears to be associated with stress and fatigue, and it shows a positive relationship with socioeconomic level and education. Scientific explanations of déjà vu fall into 4 categories: dual processing (2 cognitive processes momentarily out of synchrony), neurological (seizure, disruption in neuronal transmission), memory (implicit familiarity of unrecognized stimuli),and attentional (unattended perception followed by attended perception). Systematic research is needed on the prevalence and etiology of this culturally familiar cognitive experience, and several laboratory models may help clarify this illusion of recognition. 相似文献