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991.
The present study is an investigation of the relationships of sociometric status, gender, and academic achievement to loneliness levels of Turkish adolescents. Participants were 370 secondary school students (186 girls and 184 boys). Data on loneliness and social dissatisfaction levels of students were collected with the Turkish version of S. R. Asher and V. A. Wheeler's (1985) Loneliness and Social Dissatisfaction Scale. Sociometric data were gathered by using a rating scale and a positive nomination measure devised by S. R. Asher and K. A. Dodge (1986) in which participants were classified into one of four groups (popular, rejected, neglected, and controversial). The scores obtained from these measures were treated by a method similar to that of J. D. Coie, K. A. Dodge, and H. Coppotelli's (1982) standard score approach. Results revealed that sociometric status was significantly related to loneliness and social dissatisfaction as a function of peer relations. Members of the rejected group reported significantly higher levels of loneliness and social dissatisfaction than did members of the controversial, popular, and neglected groups. The controversial group was also significantly different from the popular group in loneliness level. No significant gender differences were found. Results also revealed a significant negative relationship between achievement scores and loneliness, indicating that as the level of loneliness increased, academic achievement decreased.  相似文献   
992.
Among a sample of 176 low-income mothers from 3 ethnic groups in the United States, the authors investigated ethnic differences in attitudes toward preferred parenting strategies, or styles; ethnic differences in the potential for child abuse; and the relationship between parenting strategies, the potential for child abuse, and parental satisfaction. They distributed the Maternal Reactions to Child's Deviant Behavior subscale (K. M. Rickard, W. Graziano, & R. Forehand, 1984), a shortened version of the Child Abuse Potential Inventory (CAPI; J. S. Milner & R. C. Wimberley, 1979), and a Parental Satisfaction Scale (N. P Medora, S. M. Wilson, & J. Larson, 1996) to the participants. The results indicated no significant ethnic differences in preferred parenting styles. Mothers from all 3 ethnic groups ranked praise and reasoning as the 1st and 2nd preferred parenting strategies. There were no ethnic differences in the perceived potential for child abuse. Parental satisfaction was negatively related to 2 of the CAPI subscales--Loneliness and Problems. The parenting strategy reasoning was positively correlated with parental satisfaction.  相似文献   
993.
A theoretical model of well-being identifies 6 key components that have been examined primarily in older adults (e.g., C. D. Ryff, 1989c, 1991): self-acceptance, positive relations with others, autonomy, environmental mastery, purpose in life, and personal growth (C. D. Ryff, 1995; C. D. Ryff & C. L. M. Keyes, 1995; C. D. Ryff & B. Singer, 1996). The authors examined them in a sample of 379 Canadian university students to determine how well-being was correlated with endorsement of stereotypic gender roles and with the impostor phenomenon. The participants completed Ryff's Scales of Psychological Well-Being (Ryff, personal communication, March 1996), the Clance Impostor Phenomenon Scale (P. R. Clance & M. A. O'Toole, 1988), and the Extended Personal Attributes Questionnaire (J. T. Spence, R. L. Helmreich, & C. K. Holahan, 1979). The results supported the hypotheses that (a) people with higher scores for expressive traits score higher for well-being stemming from positive relations with others, (b) people with higher scores for instrumental traits score higher for well-being related to feelings of autonomy, (c) people with higher scores for impostor feelings (and lower scores for ability confidence) score lower for self-acceptance and (d) for environmental mastery.  相似文献   
994.
995.
The effects of manipulations of response requirement, intertrial interval (ITI), and psychoactive drugs (ethanol, phencyclidine, and d-amphetamine) on lever choice under concurrent fixed-ratio schedules were investigated in rats. Responding on the "certain' lever produced three 45-mg pellets, whereas responding on the "risky" lever produced either 15 pellets (p = .33) or no pellets (p .67). Rats earned all food during the session, which ended after 12 forced trials and 93 choice trials or 90 min, whichever occurred first. When the response requirement was increased from 1 to 16 and the ITI was 20 s, percentage of risky choice was inversely related to fixed-ratio value. When only a single response was required but the ITI was manipulated between 20 and 120 s (with maximum session duration held constant), percentage of risky choice was directly related to length of the ITI. The effects of the drugs were investigated first at an ITI of 20 s, when risky choice was low for most rats, and then at an ITI of 80 s, when risky choice was higher for most rats. Ethanol usually decreased risky choice. Phencyclidine did not usually affect risky choice when the ITI was 20 s but decreased it in half the rats when the ITI was 80 s. For d-amphetamine, the effects appeared to he related to baseline probability of risky choice; that is, low probabilities were increased and high probabilities were decreased. Although increase in risky choice as a function of the ITI is at variance with previous ITI data, it is consistent with foraging data showing that risk aversion decreases as food availability decreases. The pharmacological manipulations showed that drug effects on risky choice may be influenced by the baseline probability of risky choice, just as drug effects can be a function of baseline response rate.  相似文献   
996.
997.
Brain activity elicited by visually presented words was investigated using behavioral measures and current source densities calculated from high-resolution EEG recordings. Verbs referring to actions usually performed with different body parts were compared. Behavioral data indicated faster processing of verbs referring to actions performed with the face muscles and articulators (face-related words) compared to verbs referring to movements involving the lower half of the body (leg-related words). Significant topographical differences in brain activity elicited by verb types were found starting approximately 250 ms after word onset. Differences were seen at recording sites located over the motor strip and adjacent frontal cortex. At the vertex, close to the cortical representation of the leg, leg-related verbs (for example, to walk) produced strongest in-going currents, whereas for face-related verbs (for example, to talk) the most in-going activity was seen at more lateral electrodes placed over the left Sylvian fissure, close to the representation of the articulators. Thus, action words caused differential activation along the motor strip, with strongest in-going activity occurring close to the cortical representation of the body parts primarily used for carrying out the actions the verbs refer to. Topographically specific physiological signs of word processing started earlier for face-related words and lasted longer for verbs referring to leg movements. We conclude that verb types can differ in their processing speed and can elicit neurophysiological activity with different cortical topographies. These behavioral and physiological differences can be related to cognitive processes, in particular to lexical semantic access. Our results are consistent with associative theories postulating that words are organized in the brain as distributed cell assemblies whose cortical distributions reflect the words' meanings.  相似文献   
998.
At 6 months following the death of their spouse, 37 participants reported their grief-related symptoms and thoughts, and then, approximately 4.5 years later, they attempted to recall how they felt at the time of the 6-month report. Although participants were far less distressed at recall than initially, they recalled their 6-month grief rather accurately. Participants did however overestimate prior grief-related intrusive ideation. Participant's current level of grief predicted what they recalled slightly better than the actual initial grief. Conversely, what they recalled predicted current levels of grief across various measures. Participants whose grief diminished relatively little over time tended to overestimate prior grief more. The retrospective reappraisal that one's past grief was not severe may indicate effective coping.  相似文献   
999.
Viewpoint dependence in visual and haptic object recognition   总被引:5,自引:0,他引:5  
On the whole, people recognize objects best when they see the objects from a familiar view and worse when they see the objects from views that were previously occluded from sight. Unexpectedly, we found haptic object recognition to be viewpoint-specific as well, even though hand movements were unrestricted. This viewpoint dependence was due to the hands preferring the back "view" of the objects. Furthermore, when the sensory modalities (visual vs. haptic) differed between learning an object and recognizing it, recognition performance was best when the objects were rotated back-to-front between learning and recognition. Our data indicate that the visual system recognizes the front view of objects best, whereas the hand recognizes objects best from the back.  相似文献   
1000.
This review discusses the research published in the last five years on the behavioral, genetic, medical, and neuroscience aspects of Down syndrome. The subject areas that have experienced the most active research include Alzheimer disease, language development, leukemia, and pregnancy screening and diagnosis. These and other areas are reviewed.  相似文献   
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