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951.
Yonelinas et al. (2002) found that hypoxic patients exhibited deficits in recollection that left familiarity relatively unaffected. In contrast, Manns, Hopkins, Reed, Kitchener, and Squire (2003) studied a group of hypoxic patients who suffered severe and equivalent deficits in recollection and familiarity. We reexamine those studies and argue that the discrepancy in results is likely due to differences in the hypoxic groups that were tested (i.e., differences in amnestic severity, subject sampling methods, and patient etiology). Yonelinas et al. examined memory in 56 cardiac arrest patients who suffered a brief hypoxic event, whereas Manns et al. examined a group of severely amnesic patients that consisted of 2 cardiac arrest patients, 2 heroin overdose patients, 1 carbon monoxide poisoning patient, and 2 patients with unknown etiologies. We also consider an alternative explanation proposed by Wixted and Squire (2004), who argued that the two patient groups suffered similar deficits, but that statistical or methodological artifacts distorted the results of each of Yonelinas et al.'s experiments. A consideration of those results, however, indicates that such an explanation does not account for the existing data. All of the existing evidence indicates that recollection, but not familiarity, is disrupted in mild hypoxic patients. In more severe cases of hypoxia, or those with more complex etiologies such as heroin overdose, more profound deficits may be observed.  相似文献   
952.
953.
Raters who pursue different goals give different ratings   总被引:5,自引:0,他引:5  
J. N. Cleveland and K. R. Murphy (1992) suggested that phenomena such as rater errors and interrater disagreements could be understood in terms of differences in the goals pursued by various raters. We measured 19 rating goals of students at the beginning of a semester, grouped them into scales, and correlated these with teacher evaluations collected at the end of the semester. We found significant multiple correlations, both within classes and in an analysis of the pooled sample (adjusting for instructor mean differences, incremental R2 =.08). Measures of rating goals obtained after raters had observed a significant proportion of ratee performance accounted for variance (incremental R2 =.07) not accounted for by measures of goals obtained at the beginning of the semester.  相似文献   
954.
The authors developed a model of childhood perceived peer harassment, using several personality, peer, and familial characteristics of victims, and tested it with children 10 to 11 years old (N = 3,434) drawn from the Canadian National Survey of Children and Youth, which is a stratified random sample of 22,831 households in Canada. A 3-step analytic procedure with 3 separate subsamples of the children was used to explore psychosocial correlates of peer harassment. Results from the latent variable path analysis (comparative fit index = .90) showed that victims are likely to feel anxious and disliked by their peers. Their parents reported using high levels of control and low levels of warmth with their children and reported high levels of depression and marital conflict themselves. These results are discussed from a social-cognitive perspective.  相似文献   
955.
The main purpose of this study was to identify whether a lot of sports training had any effect on the balance control associated with a leg movement. The nature of the training experience was also an important concern and we chose subject who had undergone specific training experience in absence of equilibrium constraints. To this end a comparison between control (untrained) subjects, triathletes and swimmers was designed to establish whether a general training in sports (triathletes) or a specific loadless training (swimmers), leads to differences in the balance control. A leg movement is preceded by a shift of the center of mass (CM) towards the supporting side to maintain equilibrium and forward to create the condition for progression. To provide an acceleration of the CM sideward and forward, an initial displacement of the center of pressure (CP) towards the moving limb and in posterior direction was performed. Interestingly, the lateral pressure onto the ground was greater increased in swimmers in both leg raising and obstacle avoidance tasks compared to the control group and/or triathletes whereas the backward CP shift in all group was the same. The initial control of the CM shift is very different in swimmers compared to triathletes and controls. The increased lateral pressure onto the ground in swimmers may be a result of a prolonged training in water. This suggests that prolonged training in the absence of equilibrium constraints has more of an effect on balance control than a prolonged general training. In addition, the lack of differences in the backward CP shift suggests that M/L and A/P controls support two functional goals: equilibrium maintenance and movement initiation.  相似文献   
956.
957.
The number, amplitude, duration, and bout structure of isolation-induced ultrasonic vocalization (USV) of infant rats (Rattus norvegicus) were measured on postnatal Day 10. Measurements were made before and after a brief, 1-min, active interaction with their mother or before and after a "pick-up" control procedure. Consistent with prior studies, the number of USVs emitted was significantly increased in the period following the maternal reunion but not after the control procedure. The average amplitude of USVs was also greater following maternal reunion. Finally, analyses characterizing the bout structure of USV production indicated that the average bout size (i.e. number of USVs/bout) was increased severalfold following the reunion with the mother, accounting for the greater rate of USV production during the second isolation period.  相似文献   
958.
Effects of rate building on fluent performance: a review and commentary   总被引:1,自引:0,他引:1  
The use of rate-building procedures to encourage the production of high response rates and to develop fluency has been increasingly justified by research on precision teaching and automaticity. Rate-building procedures often ensure both speed and accuracy, and claims have been made that such procedures result in greater retention, persistence, and generalization of trained skills, as well as preference by students. Given the potential importance of these claims for behavior analysts and educators alike, this review assesses the validity, generality, and implications of research on rate building. The review revealed sparse empirical evidence that retention, persistence, and generalization of skills result from the use of rate-building procedures when the effects of practice and reinforcement rate are controlled. Given the results of this review, the implications are discussed in the context of behavior-analytic research (e.g., behavioral momentum), and further research is recommended.  相似文献   
959.
In earlier work we have shown that adults, infants, and cotton-top tamarin monkeys are capable of computing the probability with which syllables occur in particular orders in rapidly presented streams of human speech, and of using these probabilities to group adjacent syllables into word-like units. We have also investigated adults' learning of regularities among elements that are not adjacent, and have found strong selectivities in their ability to learn various kinds of non-adjacent regularities. In the present paper we investigate the learning of these same non-adjacent regularities in tamarin monkeys, using the same materials and familiarization methods. Three types of languages were constructed. In one, words were formed by statistical regularities between non-adjacent syllables. Words contained predictable relations between syllables 1 and 3; syllable 2 varied. In a second type of language, words were formed by statistical regularities between non-adjacent segments. Words contained predictable relations between consonants; the vowels varied. In a third type of language, also formed by regularities between non-adjacent segments, words contained predictable relations between vowels; the consonants varied. Tamarin monkeys were exposed to these languages in the same fashion as adults (21 min of exposure to a continuous speech stream) and were then tested in a playback paradigm measuring spontaneous looking (no reinforcement). Adult subjects learned the second and third types of language easily, but failed to learn the first. However, tamarin monkeys showed a different pattern, learning the first and third type of languages but not the second. These differences held up over multiple replications, using different sounds instantiating each of the patterns. These results suggest differences among learners in the elementary units perceived in speech (syllables, consonants, and vowels) and/or the distance over which such units can be related, and therefore differences among learners in the types of patterned regularities they can acquire. Such studies with tamarins open interesting questions about the perceptual and computational capacities of human learners that may be essential for language acquisition, and how they may differ from those of non-human primates.  相似文献   
960.
In contemporary psychology, personality assessment knows few national or cultural boundaries. Psychological tests developed in one country are often translated and adapted into cultures that might appear to be greatly different from the country of origin. In this article, I address the factors that are important to international test adaptation and examine problems that can adversely affect cross-cultural test research programs. I address qualities important for verifying the accuracy and adequacy of cross-cultural assessment. I review the extensive adaptation of the MMPI (Hathaway & McKinley, 1940) and MMPI-2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989), the most frequently used personality measure. I highlight several contemporary research trends in international personality assessment.  相似文献   
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